Initial commit

2020-12-06 20:17:19 +01:00
commit d9d598b021
83 changed files with 3527 additions and 0 deletions
--- a/app/.gitignore
+++ b/app/.gitignore
@@ -0,0 +1 @@
+/build
--- a/app/app.iml
+++ b/app/app.iml
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -0,0 +1,43 @@
+apply plugin: 'com.android.application'
+
+apply plugin: 'kotlin-android'
+
+apply plugin: 'kotlin-android-extensions'
+
+android {
+    compileSdkVersion 29
+    defaultConfig {
+        applicationId "de.sebse.mentalarithmetic"
+        minSdkVersion 15
+        targetSdkVersion 29
+        versionCode 1
+        versionName "1.0"
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+    }
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+    }
+}
+
+dependencies {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    implementation 'androidx.appcompat:appcompat:1.1.0'
+    implementation 'androidx.core:core-ktx:1.1.0'
+    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
+    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
+    implementation 'androidx.recyclerview:recyclerview:1.1.0'
+    implementation "androidx.cardview:cardview:1.0.0"
+    implementation "androidx.gridlayout:gridlayout:1.0.0"
+    implementation "androidx.preference:preference:1.1.0"
+    implementation "androidx.viewpager2:viewpager2:1.0.0"
+    implementation 'com.google.android.material:material:1.2.0-alpha03'
+    implementation 'me.zhanghai.android.materialprogressbar:library:1.6.1'
+    implementation 'me.relex:circleindicator:2.1.4'
+    testImplementation 'junit:junit:4.12'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
+}
--- a/app/proguard-rules.pro
+++ b/app/proguard-rules.pro
@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile
--- a/app/src/androidTest/java/de/sebse/mentalarithmetic/ExampleInstrumentedTest.kt
+++ b/app/src/androidTest/java/de/sebse/mentalarithmetic/ExampleInstrumentedTest.kt
@@ -0,0 +1,24 @@
+package de.sebse.mentalarithmetic
+
+import androidx.test.platform.app.InstrumentationRegistry
+import androidx.test.ext.junit.runners.AndroidJUnit4
+
+import org.junit.Test
+import org.junit.runner.RunWith
+
+import org.junit.Assert.*
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+@RunWith(AndroidJUnit4::class)
+class ExampleInstrumentedTest {
+    @Test
+    fun useAppContext() {
+        // Context of the app under test.
+        val appContext = InstrumentationRegistry.getInstrumentation().targetContext
+        assertEquals("de.sebse.mentalarithmetic", appContext.packageName)
+    }
+}
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="de.sebse.mentalarithmetic">
+
+    <application
+        android:allowBackup="true"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:theme="@style/AppTheme">
+        <activity android:name=".MainActivity">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>
--- a/app/src/main/ic_launcher-web.png
+++ b/app/src/main/ic_launcher-web.png
--- a/app/src/main/java/de/sebse/mentalarithmetic/MainActivity.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/MainActivity.kt
@@ -0,0 +1,100 @@
+package de.sebse.mentalarithmetic
+
+import android.os.Bundle
+import android.util.Log
+import androidx.appcompat.app.AppCompatActivity
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.FragmentTransaction
+import de.sebse.mentalarithmetic.fragments.*
+import de.sebse.mentalarithmetic.types.ItemObject
+import de.sebse.mentalarithmetic.types.TaskObject
+import de.sebse.mentalarithmetic.types.TipObject
+
+
+class MainActivity : AppCompatActivity(), TaskItemFragment.OnListFragmentInteractionListener,
+    TaskFragment.IGameListener, SummaryFragment.IGameSummaryListener {
+
+    var currentFragment: Fragment? = null
+    val CURRENT_FRAGMENT_STATE: String = "CURRENT_FRAGMENT_STATE"
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_main)
+
+        savedInstanceState?.let {
+            //Restore the fragment's instance
+            Log.d("APP", "here1")
+            val fragment = supportFragmentManager.getFragment(savedInstanceState, CURRENT_FRAGMENT_STATE)
+            fragment?.let {
+                Log.d("APP", "here")
+                val ft: FragmentTransaction = supportFragmentManager.beginTransaction()
+                ft.replace(R.id.fragment_holder, fragment)
+                ft.commit()
+                currentFragment = fragment
+                return
+            }
+        }
+
+        val fragment = TaskPagerFragment.newInstance()
+        val ft: FragmentTransaction = supportFragmentManager.beginTransaction()
+        ft.replace(R.id.fragment_holder, fragment)
+        ft.commit()
+        currentFragment = fragment
+    }
+
+    override fun onListFragmentInteraction(item: ItemObject) {
+        val fragment: Fragment? = if (item is TaskObject) {
+            item.start(applicationContext)
+            TaskFragment.newInstance(item)
+        } else if (item is TipObject) {
+            TipFragment.newInstance(item)
+        } else {
+            null
+        }
+        if (fragment != null) {
+            val ft: FragmentTransaction = supportFragmentManager.beginTransaction()
+            ft.replace(R.id.fragment_holder, fragment)
+            ft.commit()
+            currentFragment = fragment
+        }
+    }
+
+    override fun onSaveInstanceState(outState: Bundle) {
+        super.onSaveInstanceState(outState)
+        currentFragment?.let { supportFragmentManager.putFragment(outState, CURRENT_FRAGMENT_STATE, it) }
+    }
+
+    override fun onGameFinished(item: TaskObject) {
+        val fragment = SummaryFragment.newInstance(item)
+        val ft: FragmentTransaction = supportFragmentManager.beginTransaction()
+        ft.replace(R.id.fragment_holder, fragment)
+        ft.commit()
+        currentFragment = fragment
+    }
+
+    override fun onGameSummaryRetry(item: TaskObject) {
+        onListFragmentInteraction(item)
+    }
+
+    override fun onGameSummaryFinished() {
+        goToList()
+    }
+
+    fun goToList() {
+        val fragment = TaskPagerFragment.newInstance()
+        val ft: FragmentTransaction = supportFragmentManager.beginTransaction()
+        ft.replace(R.id.fragment_holder, fragment)
+        ft.commit()
+        currentFragment = fragment
+    }
+
+    override fun onBackPressed() {
+        if (currentFragment is TaskPagerFragment) {
+            if (!(currentFragment as TaskPagerFragment).previous()) {
+                super.onBackPressed()
+            }
+        } else {
+            goToList()
+        }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/fragments/SummaryFragment.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/fragments/SummaryFragment.kt
@@ -0,0 +1,96 @@
+package de.sebse.mentalarithmetic.fragments
+
+
+/*import android.inputmethodservice.Keyboard
+import android.inputmethodservice.KeyboardView
+import android.inputmethodservice.KeyboardView.OnKeyboardActionListener*/
+import android.content.Context
+import android.os.Bundle
+import android.util.Log
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.Button
+import android.widget.TextView
+import androidx.fragment.app.Fragment
+import de.sebse.mentalarithmetic.R
+import de.sebse.mentalarithmetic.types.ItemFactory
+import de.sebse.mentalarithmetic.types.TaskObject
+
+
+/**
+ * A simple [Fragment] subclass.
+ * Use the [SummaryFragment.newInstance] factory method to
+ * create an instance of this fragment.
+ */
+class SummaryFragment : Fragment() {
+    private lateinit var listener: IGameSummaryListener
+    private var item: TaskObject? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        Log.d("SummaryFragment", (savedInstanceState != null).toString())
+        arguments?.let {
+            val param1 = it.getString(ARG_PARAM1)
+            item = ItemFactory.ITEM_MAP[param1] as TaskObject
+        }
+        savedInstanceState?.let {
+            val param1 = it.getString(ARG_PARAM1)
+            item = ItemFactory.ITEM_MAP[param1] as TaskObject
+        }
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        // Inflate the layout for this fragment
+        return inflater.inflate(R.layout.fragment_summary, container, false)?.also { view ->
+            view.findViewById<Button>(R.id.retry).setOnClickListener{v -> item?.let {this.listener.onGameSummaryRetry(it)} }
+            view.findViewById<Button>(R.id.exit).setOnClickListener{v -> this.listener.onGameSummaryFinished() }
+            view.findViewById<TextView>(R.id.time).text = (item?.getLiveTime() ?: "").toString()
+        }
+    }
+
+    override fun onSaveInstanceState(outState: Bundle) {
+        super.onSaveInstanceState(outState)
+        item?.let { outState.putString(ARG_PARAM1, it.ID) }
+    }
+
+    override fun onAttach(context: Context) {
+        super.onAttach(context)
+        if (context is IGameSummaryListener) {
+            this.listener = context
+        } else {
+            throw RuntimeException(context.toString() + " must implement IGameSummaryListener")
+        }
+    }
+
+    interface IGameSummaryListener {
+        fun onGameSummaryRetry(item: TaskObject)
+        fun onGameSummaryFinished()
+    }
+
+
+    companion object {
+        // TODO: Rename parameter arguments, choose names that match
+        // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
+        private const val ARG_PARAM1 = "param1"
+
+        /**
+         * Use this factory method to create a new instance of
+         * this fragment using the provided parameters.
+         *
+         * @param param1 Parameter 1.
+         * @return A new instance of fragment SummaryFragment.
+         */
+        // TODO: Rename and change types and number of parameters
+        @JvmStatic
+        fun newInstance(param1: TaskObject) =
+            SummaryFragment().apply {
+                arguments = Bundle().apply {
+                    putString(ARG_PARAM1, param1.ID)
+                }
+            }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskFragment.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskFragment.kt
@@ -0,0 +1,261 @@
+package de.sebse.mentalarithmetic.fragments
+
+
+/*import android.inputmethodservice.Keyboard
+import android.inputmethodservice.KeyboardView
+import android.inputmethodservice.KeyboardView.OnKeyboardActionListener*/
+import android.content.Context
+import android.graphics.Typeface
+import android.os.Bundle
+import android.os.Handler
+import android.text.Spannable
+import android.text.SpannableString
+import android.text.style.StrikethroughSpan
+import android.text.style.StyleSpan
+import android.util.Log
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.TextView
+import androidx.core.content.ContextCompat
+import androidx.fragment.app.Fragment
+import de.sebse.mentalarithmetic.R
+import de.sebse.mentalarithmetic.types.ItemFactory
+import de.sebse.mentalarithmetic.types.TaskObject
+import de.sebse.mentalarithmetic.utils.BoardView
+import de.sebse.mentalarithmetic.utils.Keyboard
+import kotlinx.android.synthetic.main.fragment_task.*
+import me.zhanghai.android.materialprogressbar.MaterialProgressBar
+import kotlin.math.max
+import kotlin.math.min
+import kotlin.math.roundToInt
+
+
+/**
+ * A simple [Fragment] subclass.
+ * Use the [TaskFragment.newInstance] factory method to
+ * create an instance of this fragment.
+ */
+class TaskFragment : Fragment() {
+    //private var mKeyboardView: KeyboardView? = null
+    //private var mKeyboard: Keyboard? = null
+    // TODO: Rename and change types of parameters
+    private var item: TaskObject? = null
+    private var inputView: TextView? = null
+    private var questionView: TextView? = null
+    private var questionCorrectView: TextView? = null
+    private var questionCountView: TextView? = null
+    private var boardView: BoardView? = null
+    private var gameListener: IGameListener? = null
+
+    interface IGameListener {
+        fun onGameFinished(item: TaskObject)
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        Log.d("TaskFragment", (savedInstanceState != null).toString())
+        arguments?.let {
+            val param1 = it.getString(ARG_PARAM1)
+            item = ItemFactory.ITEM_MAP[param1] as TaskObject
+        }
+        savedInstanceState?.let {
+            val param1 = it.getString(ARG_PARAM1)
+            item = ItemFactory.ITEM_MAP[param1] as TaskObject
+        }
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        // Inflate the layout for this fragment
+        return inflater.inflate(R.layout.fragment_task, container, false)?.also { view ->
+            item?.let {
+                view.findViewById<TextView>(R.id.name).apply {
+                    text = getString(it.NAME)
+                }
+                questionView = view.findViewById<TextView>(R.id.question).apply {
+                    text = ""
+                }
+                questionCountView = view.findViewById<TextView>(R.id.question_count).apply {
+                    text = ""
+                }
+                questionCorrectView = view.findViewById<TextView>(R.id.question_correct).apply {
+                    text = ""
+                }
+                inputView = view.findViewById<TextView>(R.id.answer).apply {
+                    text = ""
+                }
+                boardView = view.findViewById<BoardView>(R.id.keyboardview).apply {
+                    setBtnListener(::btnListener)
+                    setSubmitListener(::submitListener)
+                }
+                view.findViewById<TextView>(R.id.time).let { time ->
+                view.findViewById<MaterialProgressBar>(R.id.progress2).let { progress2 ->
+                    val handler = Handler()
+                    val runnable = object : Runnable {
+                        override fun run() {
+                                time.text = it.getLiveTime().toString()
+                            val twentyPercent = it.SILVER_TIME - it.GOLD_TIME
+                            val progress100 = it.GOLD_TIME - twentyPercent
+                            val progress0 = it.GOLD_TIME + twentyPercent * 4
+                            val prog = min(progress0, max(progress100, (it.getLiveTime() / (it.getCountCurrent()+1) * it.getCountTotal()).toInt()))
+                                progress2.progress =
+                                    (100 - (prog - progress100) / (twentyPercent * 0.05)).roundToInt()
+                            handler.postDelayed(this, 50)
+                        }
+                    }
+                    handler.postDelayed(runnable, 1)
+                }}
+            }
+            setQuestion()
+        }
+    }
+
+    override fun onResume() {
+        super.onResume()
+        setQuestion()
+    }
+
+    private fun setQuestion() {
+        Log.d("ff", item?.getCurrect().toString())
+        item?.getCurrect()?.let {
+            questionView?.text = it.getQuestion()
+            view?.let { view ->
+                val keyboard = Keyboard(view.context, it.getKeyboard())
+                boardView?.setKeyboard(keyboard)
+            }
+        }
+        item?.let {
+            questionCountView?.text = getString(R.string.question_count, it.getCountCurrent())
+            questionCorrectView?.text = getString(R.string.question_currect, it.getCountCorrect(), it.COUNT)
+        }
+    }
+
+    override fun onSaveInstanceState(outState: Bundle) {
+        super.onSaveInstanceState(outState)
+        item?.let { outState.putString(ARG_PARAM1, it.ID) }
+    }
+
+    fun btnListener(code: Int) {
+        item?.let {
+            inputView?.let {v ->
+                v.text = it.getCurrect()?.translate(boardView?.getText() ?: "") ?: ""
+            }
+            it.getCurrect()?.let { current ->
+                if (!current.getMultipleInput()) {
+                    submit(listOf(code))
+                }
+            }
+        }
+    }
+
+    fun submitListener(text: List<Int>) {
+        submit(text)
+    }
+
+
+    private fun submit(text: List<Int>) {
+        item?.let {
+            val answer = text.joinToString(separator = "")
+            Log.d("FRAG", answer)
+            val (valid, correct, question) = it.answer(answer, requireContext())
+            it.pause()
+            setAnswerColor(valid, correct, it)
+            keyboardview?.lock()
+            keyboardview?.reset()
+            Handler().postDelayed({
+                if (question != null) {
+                    unsetAnswerColor()
+                    setQuestion()
+                    keyboardview?.unlock()
+                    it.resume()
+                } else {
+                    val time: Long = it.getLiveTime()
+                    val score = it.getScore(requireContext())
+                    if (time > Integer.MIN_VALUE && time < Integer.MAX_VALUE && (score == 0 || time < score)) {
+                        it.setScore(requireContext(), time.toInt())
+                    }
+                    this.gameListener?.onGameFinished(it)
+                    keyboardview?.unlock()
+                }
+            }, 300)
+
+        }
+    }
+
+    private fun setAnswerColor(valid: Boolean, correct: String, item: TaskObject) {
+        context?.let {context ->
+            val correctFormatted = item.getCurrect()?.translate(correct) ?: ""
+            val color = if (valid) {
+                ContextCompat.getColor(context, android.R.color.holo_green_light)
+            } else {
+                ContextCompat.getColor(context, android.R.color.holo_red_light)
+            }
+            keyboardview?.apply {
+                setBackgroundColor(color)
+            }
+            inputView?.apply {
+                setBackgroundColor(color)
+                if (!valid) {
+                    text = SpannableString("$text $correctFormatted").apply {
+                        setSpan(
+                            StrikethroughSpan(),
+                            0, text.length,
+                            Spannable.SPAN_EXCLUSIVE_EXCLUSIVE)
+                        setSpan(
+                            StyleSpan(Typeface.BOLD),
+                            text.length, "$text $correctFormatted".length,
+                            Spannable.SPAN_EXCLUSIVE_EXCLUSIVE)
+                    }
+                }
+            }
+        }
+    }
+
+    private fun unsetAnswerColor() {
+        context?.let {context ->
+            val color = ContextCompat.getColor(context, R.color.colorPrimaryDark)
+            keyboardview?.apply {
+                setBackgroundColor(color)
+            }
+            inputView?.apply {
+                setBackgroundColor(color)
+                text = ""
+            }
+        }
+    }
+
+    override fun onAttach(context: Context) {
+        super.onAttach(context)
+        if (context is IGameListener) {
+            this.gameListener = context
+        } else {
+            throw RuntimeException(context.toString() + " must implement IGameListener")
+        }
+    }
+
+
+    companion object {
+        // TODO: Rename parameter arguments, choose names that match
+        // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
+        private const val ARG_PARAM1 = "param1"
+
+        /**
+         * Use this factory method to create a new instance of
+         * this fragment using the provided parameters.
+         *
+         * @param param1 Parameter 1.
+         * @return A new instance of fragment TaskFragment.
+         */
+        // TODO: Rename and change types and number of parameters
+        @JvmStatic
+        fun newInstance(param1: TaskObject) =
+            TaskFragment().apply {
+                arguments = Bundle().apply {
+                    putString(ARG_PARAM1, param1.ID)
+                }
+            }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskItemAdapter.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskItemAdapter.kt
@@ -0,0 +1,144 @@
+package de.sebse.mentalarithmetic.fragments
+
+import android.util.Log
+import androidx.recyclerview.widget.RecyclerView
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.TextView
+import com.google.android.material.textview.MaterialTextView
+import de.sebse.mentalarithmetic.R
+
+
+import de.sebse.mentalarithmetic.fragments.TaskItemFragment.OnListFragmentInteractionListener
+import de.sebse.mentalarithmetic.types.ItemObject
+import de.sebse.mentalarithmetic.types.TaskObject
+import de.sebse.mentalarithmetic.types.TipObject
+import de.sebse.mentalarithmetic.types.getString
+
+import kotlinx.android.synthetic.main.fragment_taskitem.view.*
+import kotlinx.android.synthetic.main.fragment_taskitem.view.content
+import kotlinx.android.synthetic.main.fragment_tipitem.view.*
+import me.zhanghai.android.materialprogressbar.MaterialProgressBar
+import kotlin.math.max
+import kotlin.math.min
+import kotlin.math.roundToInt
+
+/**
+ * [RecyclerView.Adapter] that can display a [TaskObject] and makes a call to the
+ * specified [OnListFragmentInteractionListener].
+ * TODO: Replace the implementation with code for your data type.
+ */
+class TaskItemAdapter(
+    private val mValues: List<ItemObject>,
+    private val mListener: OnListFragmentInteractionListener?
+) : RecyclerView.Adapter<TaskItemAdapter.ViewHolder>() {
+
+    private val mOnClickListener: View.OnClickListener
+
+    init {
+        mOnClickListener = View.OnClickListener { v ->
+            val item = v.tag as ItemObject
+            // Notify the active callbacks interface (the activity, if the fragment is attached to
+            // one) that an item has been selected.
+            mListener?.onListFragmentInteraction(item)
+        }
+    }
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
+        return if (viewType == 0) ViewHolderTask(LayoutInflater.from(parent.context)
+            .inflate(R.layout.fragment_taskitem, parent, false))
+        else {
+            val view = LayoutInflater.from(parent.context)
+                .inflate(R.layout.fragment_tipitem, parent, false)
+            Log.d("TIP", view.toString())
+            ViewHolderTip(view)
+        }
+    }
+
+    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
+        val item = mValues[position]
+        holder.mContentView.text = holder.mView.context.getString(item.NAME)
+
+
+        if (item is TaskObject) {
+            holder as ViewHolderTask
+            holder.mPersonalTime.text = holder.mView.context.getString(R.string.time, item.getScore(holder.mView.context) / 1000, item.getScore(holder.mView.context) % 1000)
+            holder.mGoldTime.text = (item.GOLD_TIME / 1000).toString()
+            holder.mSilverTime.text = (item.SILVER_TIME / 1000).toString()
+
+            val score = item.getScore(holder.mView.context)
+            if (score > 0) {
+                val twentyPercent = item.SILVER_TIME - item.GOLD_TIME
+                val progress100 = item.GOLD_TIME - twentyPercent
+                val progress0 = item.GOLD_TIME + twentyPercent * 4
+                val progress = min(progress0, max(progress100, score))
+                holder.mProgressView.progress = (100 - (progress - progress100) / (twentyPercent * 0.05)).roundToInt()
+
+                if (score < item.SILVER_TIME) {
+                    holder.mSilverTime.setCompoundDrawablesWithIntrinsicBounds(R.drawable.ic_star_silver, 0, 0, 0)
+                }
+                if (score < item.GOLD_TIME) {
+                    holder.mGoldTime.setCompoundDrawablesWithIntrinsicBounds(R.drawable.ic_star_gold, 0, 0, 0)
+                }
+            }
+        } else {
+            holder as ViewHolderTip
+            holder.mDescription.text = holder.mView.context.getString(item.DESCRIPTION)
+        }
+
+        if (position > 0) {
+            var previous: TaskObject?
+            var pos = position
+            do {
+                pos--
+                previous = if (mValues[pos] is TaskObject) mValues[pos] as TaskObject else null
+            } while (previous == null && pos > 0)
+            if (previous != null && (previous.getScore(holder.mView.context) == 0 || previous.getScore(holder.mView.context) > previous.SILVER_TIME)) {
+                holder.mView.alpha = 0.5f
+                with(holder.mView) {
+                    tag = item
+                    setOnClickListener(mOnClickListener)
+                }
+                return
+            }
+        }
+
+        holder.mView.alpha = 1f
+        with(holder.mView) {
+            tag = item
+            setOnClickListener(mOnClickListener)
+        }
+
+    }
+
+    override fun getItemViewType(position: Int): Int {
+        val item = mValues[position]
+        return if (item is TaskObject) {
+            0
+        } else {
+            1
+        }
+    }
+
+    override fun getItemCount(): Int = mValues.size
+
+    open inner class ViewHolder(open val mView: View): RecyclerView.ViewHolder(mView) {
+        val mContentView: TextView by lazy { mView.content }
+
+        override fun toString(): String {
+            return super.toString() + " '" + mContentView.text + "'"
+        }
+    }
+
+    inner class ViewHolderTask(override val mView: View): ViewHolder(mView) {
+        val mProgressView: MaterialProgressBar = mView.progress2
+        val mGoldTime: MaterialTextView = mView.gold_time
+        val mSilverTime: MaterialTextView = mView.silver_time
+        val mPersonalTime: MaterialTextView = mView.personal_time
+    }
+
+    inner class ViewHolderTip(override val mView: View): ViewHolder(mView) {
+        val mDescription: MaterialTextView = mView.description
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskItemFragment.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskItemFragment.kt
@@ -0,0 +1,86 @@
+package de.sebse.mentalarithmetic.fragments
+
+import android.content.Context
+import android.os.Bundle
+import androidx.fragment.app.Fragment
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import de.sebse.mentalarithmetic.R
+import de.sebse.mentalarithmetic.types.Categories
+
+import de.sebse.mentalarithmetic.types.ItemFactory
+import de.sebse.mentalarithmetic.types.ItemObject
+import de.sebse.mentalarithmetic.types.TaskObject
+
+/**
+ * A fragment representing a list of Items.
+ * Activities containing this fragment MUST implement the
+ * [TaskItemFragment.OnListFragmentInteractionListener] interface.
+ */
+class TaskItemFragment : Fragment() {
+    private val KEY_CATEGORY: String = "KEY_CATEGORY"
+
+    private var listener: OnListFragmentInteractionListener? = null
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        val view = inflater.inflate(R.layout.fragment_taskitem_list, container, false)
+
+        // Set the adapter
+        if (view is RecyclerView) {
+            with(view) {
+                layoutManager = LinearLayoutManager(context)
+                adapter = TaskItemAdapter(ItemFactory.CATEGORIES_LIST[arguments?.get(KEY_CATEGORY)] ?: ArrayList(), listener)
+            }
+        }
+        return view
+    }
+
+    override fun onAttach(context: Context) {
+        super.onAttach(context)
+        if (context is OnListFragmentInteractionListener) {
+            listener = context
+        } else {
+            throw RuntimeException(context.toString() + " must implement OnListFragmentInteractionListener")
+        }
+    }
+
+    override fun onDetach() {
+        super.onDetach()
+        listener = null
+    }
+
+    /**
+     * This interface must be implemented by activities that contain this
+     * fragment to allow an interaction in this fragment to be communicated
+     * to the activity and potentially other fragments contained in that
+     * activity.
+     *
+     *
+     * See the Android Training lesson
+     * [Communicating with Other Fragments](http://developer.android.com/training/basics/fragments/communicating.html)
+     * for more information.
+     */
+    interface OnListFragmentInteractionListener {
+        // TODO: Update argument type and name
+        fun onListFragmentInteraction(item: ItemObject)
+    }
+
+    companion object {
+
+        // TODO: Customize parameter initialization
+        @JvmStatic
+        fun newInstance(category: Categories): TaskItemFragment {
+            return TaskItemFragment().apply {
+                arguments = Bundle().apply {
+                    putSerializable(KEY_CATEGORY, category)
+                }
+            }
+        }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskPagerAdapter.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskPagerAdapter.kt
@@ -0,0 +1,15 @@
+package de.sebse.mentalarithmetic.fragments
+
+import android.util.Log
+import androidx.fragment.app.Fragment
+import androidx.viewpager2.adapter.FragmentStateAdapter
+import de.sebse.mentalarithmetic.types.ItemFactory
+
+class TaskPagerAdapter(fragment: Fragment) : FragmentStateAdapter(fragment) {
+    override fun getItemCount(): Int {
+        Log.d("Adapter", ItemFactory.CATEGORIES.size.toString())
+        return ItemFactory.CATEGORIES.size
+    }
+
+    override fun createFragment(position: Int): Fragment = TaskItemFragment.newInstance(ItemFactory.CATEGORIES[position])
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskPagerFragment.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/fragments/TaskPagerFragment.kt
@@ -0,0 +1,50 @@
+package de.sebse.mentalarithmetic.fragments
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+import androidx.viewpager2.widget.ViewPager2
+import de.sebse.mentalarithmetic.R
+import kotlinx.android.synthetic.main.fragment_taskitem_pager.view.*
+import me.relex.circleindicator.CircleIndicator3
+
+class TaskPagerFragment : Fragment() {
+
+    private lateinit var viewPager: ViewPager2
+    private lateinit var titleStrip: CircleIndicator3
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        val view = inflater.inflate(R.layout.fragment_taskitem_pager, container, false)
+        viewPager = view.findViewById(R.id.pager)
+        viewPager.adapter = TaskPagerAdapter(this)
+        titleStrip = view.findViewById(R.id.titlestrip)
+
+        titleStrip.setViewPager(viewPager)
+
+        return view
+    }
+
+    fun previous(): Boolean {
+        return if (viewPager.currentItem > 0) {
+            viewPager.currentItem--
+            true
+        } else {
+            false
+        }
+    }
+
+    companion object {
+
+        // TODO: Customize parameter initialization
+        @JvmStatic
+        fun newInstance() =
+            TaskPagerFragment().apply {
+                arguments = Bundle()
+            }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/fragments/TipFragment.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/fragments/TipFragment.kt
@@ -0,0 +1,83 @@
+package de.sebse.mentalarithmetic.fragments
+
+import android.os.Build
+import android.os.Bundle
+import android.text.Html
+import android.util.Log
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.TextView
+import androidx.core.text.HtmlCompat
+import androidx.fragment.app.Fragment
+import de.sebse.mentalarithmetic.R
+import de.sebse.mentalarithmetic.types.ItemFactory
+import de.sebse.mentalarithmetic.types.TaskObject
+import de.sebse.mentalarithmetic.types.TipObject
+import de.sebse.mentalarithmetic.utils.ImageGetter
+import de.sebse.mentalarithmetic.utils.TagHandler
+import kotlinx.android.synthetic.main.fragment_tip.view.*
+
+
+/**
+ * A simple [Fragment] subclass.
+ * Use the [TipFragment.newInstance] factory method to
+ * create an instance of this fragment.
+ */
+class TipFragment : Fragment() {
+    private var item: TipObject? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        Log.d("TaskFragment", (savedInstanceState != null).toString())
+        arguments?.let {
+            val param1 = it.getString(ARG_PARAM1)
+            item = ItemFactory.ITEM_MAP[param1] as TipObject
+        }
+        savedInstanceState?.let {
+            val param1 = it.getString(ARG_PARAM1)
+            item = ItemFactory.ITEM_MAP[param1] as TipObject
+        }
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        // Inflate the layout for this fragment
+        return inflater.inflate(R.layout.fragment_tip, container, false)?.also { view ->
+            item?.let {
+                val name = view.name
+                name.text = HtmlCompat.fromHtml(getString(it.HTML), HtmlCompat.FROM_HTML_MODE_LEGACY, ImageGetter(requireContext()), TagHandler())
+            }
+        }
+    }
+
+    override fun onSaveInstanceState(outState: Bundle) {
+        super.onSaveInstanceState(outState)
+        item?.let { outState.putString(ARG_PARAM1, it.ID) }
+    }
+
+
+    companion object {
+        // TODO: Rename parameter arguments, choose names that match
+        // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
+        private const val ARG_PARAM1 = "param1"
+
+        /**
+         * Use this factory method to create a new instance of
+         * this fragment using the provided parameters.
+         *
+         * @param param1 Parameter 1.
+         * @return A new instance of fragment TaskFragment.
+         */
+        // TODO: Rename and change types and number of parameters
+        @JvmStatic
+        fun newInstance(param1: TipObject) =
+            TipFragment().apply {
+                arguments = Bundle().apply {
+                    putString(ARG_PARAM1, param1.ID)
+                }
+            }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/Categories.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/Categories.kt
@@ -0,0 +1,7 @@
+package de.sebse.mentalarithmetic.types
+
+enum class Categories {
+    BASIC,
+    TRICKS,
+    TIME
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/ItemFactory.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/ItemFactory.kt
@@ -0,0 +1,72 @@
+package de.sebse.mentalarithmetic.types
+
+import androidx.annotation.StringRes
+import de.sebse.mentalarithmetic.R
+import java.util.*
+import kotlin.collections.ArrayList
+import kotlin.collections.HashMap
+
+object ItemFactory {
+    /**
+     * An array of sample (dummy) items.
+     */
+    val ITEMS: MutableList<ItemObject> = ArrayList()
+
+    /**
+     * A map of sample (dummy) items, by ID.
+     */
+    val ITEM_MAP: MutableMap<String, ItemObject> = HashMap()
+
+    val CATEGORIES: MutableList<Categories> = ArrayList()
+
+    val CATEGORIES_MAP: MutableMap<Categories, MutableMap<String, ItemObject>> = EnumMap(Categories::class.java)
+
+    val CATEGORIES_LIST: MutableMap<Categories, MutableList<ItemObject>> = EnumMap(Categories::class.java)
+
+    init {
+        addItem(Tip0101)
+        addItem(Task0101)
+        addItem(Task0102)
+        addItem(Task0103)
+
+        addItem(Tip0201)
+        addItem(Task0201)
+        addItem(Tip0202)
+        addItem(Task0202)
+        addItem(Task0203)
+        addItem(Task0204)
+        addItem(Task0205)
+        addItem(Task0206)
+        addItem(Task0207)
+        addItem(Task0208)
+        addItem(Tip0203)
+        addItem(Task0209)
+        addItem(Tip0204)
+        addItem(Task0210)
+        addItem(Task0211)
+        addItem(Task0212)
+        addItem(Task0213)
+        addItem(Task0214)
+        addItem(Task0215)
+        addItem(Task0216)
+    }
+
+    private fun addItem(item: ItemObject) {
+        val category = item.CATEGORY
+        if (!CATEGORIES.contains(category)) {
+            CATEGORIES.add(category)
+        }
+
+        if (!CATEGORIES_MAP.containsKey(category))
+            CATEGORIES_MAP[category] = HashMap()
+        CATEGORIES_MAP[category]!![item.ID] = item
+
+        if (!CATEGORIES_LIST.containsKey(category))
+            CATEGORIES_LIST[category] = ArrayList()
+        CATEGORIES_LIST[category]!!.add(item)
+
+        ITEMS.add(item)
+
+        ITEM_MAP[item.ID] = item
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/ItemObject.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/ItemObject.kt
@@ -0,0 +1,12 @@
+package de.sebse.mentalarithmetic.types
+
+import android.content.Context
+import androidx.annotation.StringRes
+import java.util.prefs.Preferences
+
+abstract class ItemObject {
+    abstract val ID: String
+    abstract val NAME: Int
+    abstract val DESCRIPTION: Int
+    abstract val CATEGORY: Categories
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/Preferences.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/Preferences.kt
@@ -0,0 +1,56 @@
+package de.sebse.mentalarithmetic.types
+
+import android.content.Context
+import androidx.preference.PreferenceManager
+
+
+fun set(context: Context, key: String, value: Int) {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    val editor = settings.edit()
+    editor.putInt(key, value)
+    editor.apply()
+}
+
+fun set(context: Context, key: String, value: String) {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    val editor = settings.edit()
+    editor.putString(key, value)
+    editor.apply()
+}
+
+fun set(context: Context, key: String, value: Boolean) {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    val editor = settings.edit()
+    editor.putBoolean(key, value)
+    editor.apply()
+}
+
+fun set(context: Context, key: String, value: Float) {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    val editor = settings.edit()
+    editor.putFloat(key, value)
+    editor.apply()
+}
+
+
+
+fun getInt(context: Context, key: String): Int? {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    return if (settings.contains(key)) settings.getInt(key, -1) else null
+}
+
+fun getString(context: Context, key: String): String? {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    return if (settings.contains(key)) settings.getString(key, null) else null
+}
+
+fun getBoolean(context: Context, key: String): Boolean? {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    return if (settings.contains(key)) settings.getBoolean(key, false) else null
+}
+
+fun getFloat(context: Context, key: String): Float? {
+    val settings = PreferenceManager.getDefaultSharedPreferences(context)
+    return if (settings.contains(key)) settings.getFloat(key, -1f) else null
+}
+
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/Question.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/Question.kt
@@ -0,0 +1,30 @@
+package de.sebse.mentalarithmetic.types
+
+import android.content.Context
+import androidx.annotation.XmlRes
+
+class Question(private val mQuestion: String, private val mAnswer: String, @XmlRes private val mKeyboard: Int, private val mMultipleInput: Boolean, private val translateValue: Function1<String, String>? = null) {
+    private var mGivenAnswer: String? = null
+
+    fun getQuestion(): String {
+        return mQuestion
+    }
+
+    fun getMultipleInput(): Boolean {
+        return mMultipleInput
+    }
+
+    fun translate(value: String): String {
+        return this.translateValue?.let{ it(value) } ?: value
+    }
+
+    @XmlRes
+    fun getKeyboard(): Int {
+        return mKeyboard
+    }
+
+    fun setAnswer(answer: String): Pair<Boolean, String> {
+        mGivenAnswer = answer
+        return Pair(mAnswer == mGivenAnswer, mAnswer)
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/TaskObject.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/TaskObject.kt
@@ -0,0 +1,90 @@
+package de.sebse.mentalarithmetic.types
+
+import android.content.Context
+import androidx.annotation.StringRes
+import java.util.prefs.Preferences
+
+abstract class TaskObject: ItemObject() {
+    abstract val COUNT: Int
+    abstract val SILVER_TIME: Int
+    abstract val GOLD_TIME: Int
+
+    private var paused: Boolean = false
+    private var startTime: Long = 0
+    private var elapsedTime: Long = 0
+    private var questionCount: Int = 0
+    private var questionCorrect: Int = 0
+    private var question: Question? = null
+
+
+    protected abstract fun generateQuestion(context: Context): Question
+
+    fun start(context: Context): Question? {
+        startTime = System.currentTimeMillis()
+        elapsedTime = 0
+        questionCount = 0
+        questionCorrect = 0
+        paused = false
+        return nextQuestion(context)
+    }
+
+    fun getCurrect(): Question? = question
+
+    fun answer(answer: String, context: Context): Triple<Boolean, String, Question?> {
+        return question?.let {
+            val (valid, correct) = question!!.setAnswer(answer)
+            if (valid)
+                questionCorrect++
+            return Triple(valid, correct, nextQuestion(context))
+        } ?: Triple(true, "", null)
+    }
+
+    fun pause() {
+        elapsedTime += System.currentTimeMillis() - startTime
+        paused = true
+    }
+
+    fun resume() {
+        startTime = System.currentTimeMillis()
+        paused = false
+    }
+
+    fun getLiveTime(): Long {
+        return if (paused) {
+            elapsedTime
+        } else {
+            elapsedTime + System.currentTimeMillis() - startTime
+        }
+    }
+
+    fun getCountCurrent(): Int {
+        return questionCount
+    }
+
+    fun getCountCorrect(): Int {
+        return questionCorrect
+    }
+
+    fun getCountTotal(): Int {
+        return questionCount + COUNT - questionCorrect
+    }
+
+    fun getScore(context: Context): Int {
+        return getInt(context, "TaskObject.$ID.score") ?: 0
+    }
+
+    fun setScore(context: Context, score: Int) {
+        set(context, "TaskObject.$ID.score", score)
+    }
+
+    private fun nextQuestion(context: Context): Question? {
+        questionCount++
+        elapsedTime += System.currentTimeMillis() - startTime
+        startTime = System.currentTimeMillis()
+        question = if (questionCorrect >= COUNT)
+            null
+        else
+            generateQuestion(context)
+        return question
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/TaskObjects.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/TaskObjects.kt
@@ -0,0 +1,395 @@
+package de.sebse.mentalarithmetic.types
+
+import android.content.Context
+import de.sebse.mentalarithmetic.R
+import java.util.*
+import kotlin.random.Random
+
+object Task0101: TaskObject() {
+    override val ID: String             = "Task-01-01"
+    override val NAME: Int              = R.string.task_01_01_name
+    override val DESCRIPTION: Int       = R.string.task_01_01_desc
+    override val CATEGORY: Categories   = Categories.BASIC
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 15 * 1000
+    override val GOLD_TIME: Int         = 10 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val num: Int = (0..99).random()
+        return Question(num.toString(), (num % 2).toString(), R.xml.keyboard_odd, false) { value -> when (value) {
+            "0" -> context.getString(R.string.even)
+            "1" -> context.getString(R.string.odd)
+            else -> value
+        }.toUpperCase(Locale.getDefault()) }
+    }
+}
+
+object Task0102: TaskObject() {
+    override val ID: String             = "Task-01-02"
+    override val NAME: Int              = R.string.task_01_02_name
+    override val DESCRIPTION: Int       = R.string.task_01_02_desc
+    override val CATEGORY: Categories   = Categories.BASIC
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 25 * 1000
+    override val GOLD_TIME: Int         = 15 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val sum: Int = (2..9).random()
+        val num1: Int = (1 until sum).random()
+        val num2 = sum - num1
+        return Question("$num1 + $num2", sum.toString(), R.xml.keyboard_decimal, false)
+    }
+}
+
+object Task0103: TaskObject() {
+    override val ID: String             = "Task-01-03"
+    override val NAME: Int              = R.string.task_01_03_name
+    override val DESCRIPTION: Int       = R.string.task_01_03_desc
+    override val CATEGORY: Categories   = Categories.BASIC
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val num1: Int = (1..9).random()
+        val num2: Int = (1..9).random()
+        val sum = num1 + num2
+        return Question("$num1 + $num2", sum.toString(), R.xml.keyboard_decimal_multi, true)
+    }
+}
+
+object Task0104: TaskObject() {
+    override val ID: String             = "Task-01-04"
+    override val NAME: Int              = R.string.task_01_04_name
+    override val DESCRIPTION: Int       = R.string.task_01_04_desc
+    override val CATEGORY: Categories   = Categories.BASIC
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val num1: Int = (1..9).random() + 10 * (1..3).random()
+        val num2: Int = (1..9).random() + 10 * (1..3).random()
+        val sum = num1 + num2
+        return Question("$num1 + $num2", sum.toString(), R.xml.keyboard_decimal_multi, true)
+    }
+}
+
+object Task0105: TaskObject() {
+    override val ID: String             = "Task-01-05"
+    override val NAME: Int              = R.string.task_01_05_name
+    override val DESCRIPTION: Int       = R.string.task_01_05_desc
+    override val CATEGORY: Categories   = Categories.BASIC
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val num1: Int = (10..99).random()
+        val num2: Int = (10..99).random()
+        val sum = num1 + num2
+        return Question("$num1 + $num2", sum.toString(), R.xml.keyboard_decimal_multi, true)
+    }
+}
+
+object Task0201: TaskObject() {
+    override val ID: String             = "Task-02-01"
+    override val NAME: Int              = R.string.task_02_01_name
+    override val DESCRIPTION: Int       = R.string.task_02_01_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val res: Int = (0..6).random()
+        val question = when (res) {
+            0 -> context.getString(R.string.sunday)
+            1 -> context.getString(R.string.monday)
+            2 -> context.getString(R.string.tuesday)
+            3 -> context.getString(R.string.wednesday)
+            4 -> context.getString(R.string.thursday)
+            5 -> context.getString(R.string.friday)
+            6 -> context.getString(R.string.saturday)
+            else -> ""
+        }
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0202: TaskObject() {
+    override val ID: String             = "Task-02-02"
+    override val NAME: Int              = R.string.task_02_02_name
+    override val DESCRIPTION: Int       = R.string.task_02_02_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val month: Int = (0..2).random()
+        val (res, question) = getMonthDetails(month, context)
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0203: TaskObject() {
+    override val ID: String             = "Task-02-03"
+    override val NAME: Int              = R.string.task_02_03_name
+    override val DESCRIPTION: Int       = R.string.task_02_03_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val month: Int = (3..5).random()
+        val (res, question) = getMonthDetails(month, context)
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0204: TaskObject() {
+    override val ID: String             = "Task-02-04"
+    override val NAME: Int              = R.string.task_02_04_name
+    override val DESCRIPTION: Int       = R.string.task_02_04_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val month: Int = (0..5).random()
+        val (res, question) = getMonthDetails(month, context)
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0205: TaskObject() {
+    override val ID: String             = "Task-02-05"
+    override val NAME: Int              = R.string.task_02_05_name
+    override val DESCRIPTION: Int       = R.string.task_02_05_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val month: Int = (6..8).random()
+        val (res, question) = getMonthDetails(month, context)
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0206: TaskObject() {
+    override val ID: String             = "Task-02-06"
+    override val NAME: Int              = R.string.task_02_06_name
+    override val DESCRIPTION: Int       = R.string.task_02_06_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val month: Int = (9..11).random()
+        val (res, question) = getMonthDetails(month, context)
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0207: TaskObject() {
+    override val ID: String             = "Task-02-07"
+    override val NAME: Int              = R.string.task_02_07_name
+    override val DESCRIPTION: Int       = R.string.task_02_07_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val month: Int = (6..11).random()
+        val (res, question) = getMonthDetails(month, context)
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0208: TaskObject() {
+    override val ID: String             = "Task-02-08"
+    override val NAME: Int              = R.string.task_02_08_name
+    override val DESCRIPTION: Int       = R.string.task_02_08_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val month: Int = (0..11).random()
+        val (res, question) = getMonthDetails(month, context)
+        return Question(question, res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0209: TaskObject() {
+    override val ID: String             = "Task-02-09"
+    override val NAME: Int              = R.string.task_02_09_name
+    override val DESCRIPTION: Int       = R.string.task_02_09_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val day: Int = (0..31).random()
+        val res = day % 7
+        return Question("$day mod 7", res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0210: TaskObject() {
+    override val ID: String             = "Task-02-10"
+    override val NAME: Int              = R.string.task_02_10_name
+    override val DESCRIPTION: Int       = R.string.task_02_10_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val year: Int = (0..99).random()
+        val res = year / 4
+        return Question("$year div 4", res.toString(), R.xml.keyboard_decimal_multi, true)
+    }
+}
+
+object Task0211: TaskObject() {
+    override val ID: String             = "Task-02-11"
+    override val NAME: Int              = R.string.task_02_11_name
+    override val DESCRIPTION: Int       = R.string.task_02_11_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 15
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val year: Int = (0..99).random()
+        val res = year + (year / 4)
+        return Question("$year + ($year div 4)", res.toString(), R.xml.keyboard_decimal_multi, true)
+    }
+}
+
+object Task0212: TaskObject() {
+    override val ID: String             = "Task-02-12"
+    override val NAME: Int              = R.string.task_02_12_name
+    override val DESCRIPTION: Int       = R.string.task_02_12_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val year: Int = (0..99).random()
+        val year2 = year + (year / 4)
+        val res = year2 % 7
+        return Question("$year2 % 7", res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0213: TaskObject() {
+    override val ID: String             = "Task-02-13"
+    override val NAME: Int              = R.string.task_02_13_name
+    override val DESCRIPTION: Int       = R.string.task_02_13_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 10
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val year: Int = (0..99).random()
+        val year2 = year + (year / 4)
+        val res = year2 % 7
+        return Question("($year + ($year div 4)) % 7", res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0214: TaskObject() {
+    override val ID: String             = "Task-02-14"
+    override val NAME: Int              = R.string.task_02_14_name
+    override val DESCRIPTION: Int       = R.string.task_02_14_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 10
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val century: Int = (16..22).random()
+        val year: Int = (0..99).random()
+        val year2 = year + (year / 4)
+        val res = year2 % 7
+        return Question("Year code of $century$year", res.toString(), R.xml.keyboard_dec7, false)
+    }
+}
+
+object Task0215: TaskObject() {
+    override val ID: String             = "Task-02-15"
+    override val NAME: Int              = R.string.task_02_15_name
+    override val DESCRIPTION: Int       = R.string.task_02_15_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val century: Int = (16..22).random()
+        val year: Int = (0..99).random()
+        val res = 2 * ((3 - century) % 4)
+        return Question("Century code of $century$year", res.toString(), R.xml.keyboard_decimal, false)
+    }
+}
+
+object Task0216: TaskObject() {
+    override val ID: String             = "Task-02-16"
+    override val NAME: Int              = R.string.task_02_16_name
+    override val DESCRIPTION: Int       = R.string.task_02_16_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val COUNT: Int             = 20
+    override val SILVER_TIME: Int       = 60 * 1000
+    override val GOLD_TIME: Int         = 25 * 1000
+
+    override fun generateQuestion(context: Context): Question {
+        val century: Int = (16..22).random()
+        val year: Int = (0..99).random()
+        val res = if (year % 4 == 0 && (century % 4 == 0 || year != 0)) 1 else 0
+        return Question("Is $century${if (year < 10) "0" else ""}$year a leap yeaar?", res.toString(), R.xml.keyboard_yes_no, false) { value -> when (value) {
+            "0" -> context.getString(R.string.no)
+            "1" -> context.getString(R.string.yes)
+            else -> value
+        }.toUpperCase(Locale.getDefault()) }
+    }
+}
+
+
+
+
+
+
+
+private fun getMonthDetails(
+    month: Int,
+    context: Context
+): Pair<Int, String> {
+    return when (month) {
+        0 -> Pair(0, context.getString(R.string.january))
+        1 -> Pair(3, context.getString(R.string.february))
+        2 -> Pair(3, context.getString(R.string.march))
+        3 -> Pair(6, context.getString(R.string.april))
+        4 -> Pair(1, context.getString(R.string.may))
+        5 -> Pair(4, context.getString(R.string.june))
+        6 -> Pair(6, context.getString(R.string.july))
+        7 -> Pair(2, context.getString(R.string.august))
+        8 -> Pair(5, context.getString(R.string.september))
+        9 -> Pair(0, context.getString(R.string.october))
+        10 -> Pair(3, context.getString(R.string.november))
+        11 -> Pair(5, context.getString(R.string.december))
+        else -> Pair(0, "")
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/TipObject.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/TipObject.kt
@@ -0,0 +1,9 @@
+package de.sebse.mentalarithmetic.types
+
+import android.content.Context
+import androidx.annotation.StringRes
+import java.util.prefs.Preferences
+
+abstract class TipObject: ItemObject() {
+    abstract val HTML: Int
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/types/TipObjects.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/types/TipObjects.kt
@@ -0,0 +1,43 @@
+package de.sebse.mentalarithmetic.types
+
+import de.sebse.mentalarithmetic.R
+
+object Tip0101: TipObject() {
+    override val ID: String             = "Tip-01-01"
+    override val NAME: Int              = R.string.tip_01_01_name
+    override val DESCRIPTION: Int       = R.string.tip_01_01_desc
+    override val CATEGORY: Categories   = Categories.BASIC
+    override val HTML: Int              = R.string.tip_01_01_html
+}
+
+object Tip0201: TipObject() {
+    override val ID: String             = "Tip-02-01"
+    override val NAME: Int              = R.string.tip_02_01_name
+    override val DESCRIPTION: Int       = R.string.tip_02_01_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val HTML: Int              = R.string.tip_02_01_html
+}
+
+object Tip0202: TipObject() {
+    override val ID: String             = "Tip-03-02"
+    override val NAME: Int              = R.string.tip_02_02_name
+    override val DESCRIPTION: Int       = R.string.tip_02_02_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val HTML: Int              = R.string.tip_02_02_html
+}
+
+object Tip0203: TipObject() {
+    override val ID: String             = "Tip-03-03"
+    override val NAME: Int              = R.string.tip_02_03_name
+    override val DESCRIPTION: Int       = R.string.tip_02_03_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val HTML: Int              = R.string.tip_02_03_html
+}
+
+object Tip0204: TipObject() {
+    override val ID: String             = "Tip-03-04"
+    override val NAME: Int              = R.string.tip_02_04_name
+    override val DESCRIPTION: Int       = R.string.tip_02_04_desc
+    override val CATEGORY: Categories   = Categories.TIME
+    override val HTML: Int              = R.string.tip_02_04_html
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/utils/BoardView.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/utils/BoardView.kt
@@ -0,0 +1,115 @@
+package de.sebse.mentalarithmetic.utils
+
+import android.content.Context
+import android.util.AttributeSet
+import android.view.View
+import android.widget.Button
+import androidx.core.content.ContextCompat
+import androidx.core.view.children
+import androidx.gridlayout.widget.GridLayout
+import com.google.android.material.button.MaterialButton
+import de.sebse.mentalarithmetic.R
+
+
+class BoardView(
+    context: Context,
+    attrs: AttributeSet
+) : GridLayout(context, attrs) {
+
+    private var locked: Boolean = false
+    private var callbackSubmit: ((List<Int>) -> Unit)? = null
+    private var callback: ((Int) -> Unit)? = null
+
+    var text = ArrayList<Keyboard.Key>()
+
+    init {
+        this.setBackgroundColor(ContextCompat.getColor(context, R.color.colorPrimaryDark))
+        this.rowCount = 9
+        this.columnCount = 9
+    }
+
+    fun setKeyboard(board: Keyboard) {
+        this.rowCount = board.entries.size
+        this.columnCount = board.maxWidth
+
+        this.removeAllViews()
+
+        board.entries.forEachIndexed { index, row ->
+            var colIdx = 0
+            row.items.forEach { elem ->
+                if (elem is Keyboard.Key) {
+                    this.addView(MaterialButton(context).apply {
+                        text = elem.label
+                        if (elem.icon != null) {
+                            icon = ContextCompat.getDrawable(context, elem.icon)
+                            iconGravity = MaterialButton.ICON_GRAVITY_TEXT_START
+                        }
+                        layoutParams = LayoutParams().apply {
+                            height = LayoutParams.WRAP_CONTENT
+                            width = 0
+                            columnSpec = spec(colIdx, elem.width, 1f)
+                            rowSpec = spec(index, 1, 1f)
+                        }
+                        setOnClickListener { onClick(elem) }
+                    })
+                }
+                colIdx += elem.width
+            }
+        }
+    }
+
+    fun onClick(key: Keyboard.Key) {
+        if (this.locked)
+            return
+        when (key.code) {
+            -1 -> {
+                if (text.size > 0) text.removeAt(text.size-1)
+            }
+            -2 -> {
+                callbackSubmit?.let{ it(text.map { it.code }) }
+            }
+            -3 -> {
+                text.clear()
+            }
+            else -> {
+                text.add(key)
+            }
+        }
+        callback?.let{ it(key.code) }
+    }
+
+    fun getText(): String {
+        return text.joinToString(separator = "") { it.code.toString() }
+    }
+
+
+    fun getValues(): ArrayList<Keyboard.Key> {
+        return text
+    }
+
+    fun reset() {
+        text.clear()
+    }
+
+    fun setBtnListener(callback: Function1<Int, Unit>) {
+        this.callback = callback
+    }
+
+    fun setSubmitListener(callback: Function1<List<Int>, Unit>) {
+        this.callbackSubmit = callback
+    }
+
+    fun lock() {
+        this.locked = true
+        this.children.forEach {
+            it.isEnabled = false
+        }
+    }
+
+    fun unlock() {
+        this.locked = false
+        this.children.forEach {
+            it.isEnabled = true
+        }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/utils/ImageGetter.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/utils/ImageGetter.kt
@@ -0,0 +1,24 @@
+package de.sebse.mentalarithmetic.utils
+
+import android.content.Context
+import android.graphics.drawable.Drawable
+import android.text.Html
+import androidx.core.content.ContextCompat
+
+
+class ImageGetter(val context: Context) : Html.ImageGetter {
+    override fun getDrawable(source: String): Drawable? {
+        var id: Int
+        id = context.resources.getIdentifier(source, "drawable", context.packageName)
+        if (id == 0) { // the drawable resource wasn't found in our package, maybe it is a stock android drawable?
+            id = context.resources.getIdentifier(source, "drawable", "android")
+        }
+        return if (id == 0) { // prevent a crash if the resource still can't be found
+            null
+        } else {
+            val d: Drawable? = ContextCompat.getDrawable(context, id)
+            d?.setBounds(0, 0, d.intrinsicWidth, d.intrinsicHeight)
+            d
+        }
+    }
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/utils/Keyboard.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/utils/Keyboard.kt
@@ -0,0 +1,76 @@
+package de.sebse.mentalarithmetic.utils
+
+import android.content.Context
+import android.util.Log
+import androidx.annotation.DrawableRes
+import androidx.annotation.XmlRes
+import org.xmlpull.v1.XmlPullParser
+
+
+class Keyboard(context: Context, @XmlRes res: Int) {
+
+    val entries: ArrayList<Row> = ArrayList()
+
+    init {
+        val parser = context.getResources().getXml(res)
+        var items: ArrayList<RowElement> = ArrayList()
+        try {
+            var event: Int = parser.eventType
+            while (event != XmlPullParser.END_DOCUMENT) {
+                if (event == XmlPullParser.START_TAG) {
+                    when (parser.name) {
+                        "Row" -> {
+                            items = ArrayList()
+                        }
+                        "Key" -> {
+                            val code = parser.getAttributeIntValue(null, "codes", -1)
+                            val keyLabel = parser.getAttributeValue(null, "keyLabel") ?: ""
+                            val resource = parser.getAttributeResourceValue(null, "keyIcon", -1)
+                            val width = parser.getAttributeIntValue(null, "width", 1)
+                            items.add(Key(code, keyLabel, if (resource == -1) null else resource, width))
+                        }
+                        "Gap" -> {
+                            val width = parser.getAttributeIntValue(null, "width", 1)
+                            items.add(Gap(width))
+                        }
+                    }
+                } else if (event == XmlPullParser.END_TAG) {
+                    if ("Row" == parser.name) {
+                        entries.add(Row(items))
+                    }
+                }
+                event = parser.next()
+            }
+        } catch (e: Exception) {
+            e.printStackTrace()
+        }
+        Log.d("Keyboard", entries.toString())
+    }
+
+    val maxWidth: Int
+        get() {
+            return entries.maxBy { it.width }?.width ?: 0
+        }
+
+    data class Row(val items: ArrayList<RowElement>) {
+        val width: Int
+            get() {
+                return items.sumBy { it.width }
+            }
+    }
+
+    data class Key(
+        val code: Int,
+        val label: String,
+        @DrawableRes val icon: Int?,
+        override val width: Int
+    ): RowElement
+
+    interface RowElement {
+        val width: Int
+    }
+
+    data class Gap(
+        override val width: Int
+    ): RowElement
+}
--- a/app/src/main/java/de/sebse/mentalarithmetic/utils/TagHandler.kt
+++ b/app/src/main/java/de/sebse/mentalarithmetic/utils/TagHandler.kt
@@ -0,0 +1,84 @@
+package de.sebse.mentalarithmetic.utils
+
+import android.text.Editable
+import android.text.Html.TagHandler
+import android.text.Spannable
+import android.text.style.BulletSpan
+import android.text.style.LeadingMarginSpan
+import android.text.style.TypefaceSpan
+import android.text.style.UnderlineSpan
+import android.util.Log
+import org.xml.sax.XMLReader
+import java.util.*
+
+
+class TagHandler: TagHandler {
+    private var mListItemCount = 0
+    private val mListParents: Vector<String> = Vector()
+    override fun handleTag(
+        opening: Boolean,
+        tag: String,
+        output: Editable,
+        xmlReader: XMLReader
+    ) {
+        if (tag == "ul" || tag == "ol" || tag == "dd") {
+            if (opening) {
+                mListParents.add(tag)
+            } else mListParents.remove(tag)
+            mListItemCount = 0
+        } else if (tag == "li" && !opening) {
+            handleListTag(output)
+        } else if (tag.equals("code", ignoreCase = true)) {
+            if (opening) {
+                output.setSpan(
+                    TypefaceSpan("monospace"),
+                    output.length,
+                    output.length,
+                    Spannable.SPAN_MARK_MARK
+                )
+            } else {
+                Log.d("Code Tag", "Code tag encountered")
+                val obj = getLast(output, TypefaceSpan::class.java)
+                val where = output.getSpanStart(obj)
+                output.setSpan(TypefaceSpan("monospace"), where, output.length, 0)
+            }
+        }
+    }
+
+    private fun getLast(text: Editable, kind: Class<*>): Any? {
+        val objs: Array<out Any> = text.getSpans(0, text.length, kind)
+        return if (objs.isEmpty()) {
+            null
+        } else {
+            for (i in objs.size downTo 1) {
+                if (text.getSpanFlags(objs[i - 1]) == Spannable.SPAN_MARK_MARK) {
+                    return objs[i - 1]
+                }
+            }
+            null
+        }
+    }
+
+    private fun handleListTag(output: Editable) {
+        if (mListParents.lastElement().equals("ul")) {
+            output.append("\n")
+            val split = output.toString().split("\n").toTypedArray()
+            val lastIndex = split.size - 1
+            val start = output.length - split[lastIndex].length - 1
+            output.setSpan(BulletSpan(15 * mListParents.size), start, output.length, 0)
+        } else if (mListParents.lastElement().equals("ol")) {
+            mListItemCount++
+            output.append("\n")
+            val split = output.toString().split("\n").toTypedArray()
+            val lastIndex = split.size - 1
+            val start = output.length - split[lastIndex].length - 1
+            output.insert(start, "$mListItemCount. ")
+            output.setSpan(
+                LeadingMarginSpan.Standard(15 * mListParents.size),
+                start,
+                output.length,
+                0
+            )
+        }
+    }
+}
--- a/app/src/main/res/drawable-v24/ic_launcher_foreground.xml
+++ b/app/src/main/res/drawable-v24/ic_launcher_foreground.xml
@@ -0,0 +1,34 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:fillType="evenOdd"
+        android:pathData="M32,64C32,64 38.39,52.99 44.13,50.95C51.37,48.37 70.14,49.57 70.14,49.57L108.26,87.69L108,109.01L75.97,107.97L32,64Z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="78.5885"
+                android:endY="90.9159"
+                android:startX="48.7653"
+                android:startY="61.0927"
+                android:type="linear">
+                <item
+                    android:color="#44000000"
+                    android:offset="0.0" />
+                <item
+                    android:color="#00000000"
+                    android:offset="1.0" />
+            </gradient>
+        </aapt:attr>
+    </path>
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="nonZero"
+        android:pathData="M66.94,46.02L66.94,46.02C72.44,50.07 76,56.61 76,64L32,64C32,56.61 35.56,50.11 40.98,46.06L36.18,41.19C35.45,40.45 35.45,39.3 36.18,38.56C36.91,37.81 38.05,37.81 38.78,38.56L44.25,44.05C47.18,42.57 50.48,41.71 54,41.71C57.48,41.71 60.78,42.57 63.68,44.05L69.11,38.56C69.84,37.81 70.98,37.81 71.71,38.56C72.44,39.3 72.44,40.45 71.71,41.19L66.94,46.02ZM62.94,56.92C64.08,56.92 65,56.01 65,54.88C65,53.76 64.08,52.85 62.94,52.85C61.8,52.85 60.88,53.76 60.88,54.88C60.88,56.01 61.8,56.92 62.94,56.92ZM45.06,56.92C46.2,56.92 47.13,56.01 47.13,54.88C47.13,53.76 46.2,52.85 45.06,52.85C43.92,52.85 43,53.76 43,54.88C43,56.01 43.92,56.92 45.06,56.92Z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>
--- a/app/src/main/res/drawable/ic_backspace.xml
+++ b/app/src/main/res/drawable/ic_backspace.xml
@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M22,3L7,3c-0.69,0 -1.23,0.35 -1.59,0.88L0,12l5.41,8.11c0.36,0.53 0.9,0.89 1.59,0.89h15c1.1,0 2,-0.9 2,-2L24,5c0,-1.1 -0.9,-2 -2,-2zM19,15.59L17.59,17 14,13.41 10.41,17 9,15.59 12.59,12 9,8.41 10.41,7 14,10.59 17.59,7 19,8.41 15.41,12 19,15.59z"/>
+</vector>
--- a/app/src/main/res/drawable/ic_launcher_background.xml
+++ b/app/src/main/res/drawable/ic_launcher_background.xml
@@ -0,0 +1,170 @@
+<?xml version="1.0" encoding="utf-8"?>
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:fillColor="#008577"
+        android:pathData="M0,0h108v108h-108z" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M9,0L9,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,0L19,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,0L29,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,0L39,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,0L49,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,0L59,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,0L69,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,0L79,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M89,0L89,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M99,0L99,108"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,9L108,9"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,19L108,19"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,29L108,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,39L108,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,49L108,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,59L108,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,69L108,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,79L108,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,89L108,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M0,99L108,99"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,29L89,29"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,39L89,39"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,49L89,49"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,59L89,59"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,69L89,69"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M19,79L89,79"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M29,19L29,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M39,19L39,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M49,19L49,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M59,19L59,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M69,19L69,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+    <path
+        android:fillColor="#00000000"
+        android:pathData="M79,19L79,89"
+        android:strokeWidth="0.8"
+        android:strokeColor="#33FFFFFF" />
+</vector>
--- a/app/src/main/res/drawable/ic_launcher_foreground.xml
+++ b/app/src/main/res/drawable/ic_launcher_foreground.xml
@@ -0,0 +1,54 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="930.9091"
+    android:viewportHeight="930.9091">
+  <group android:translateX="209.45454"
+      android:translateY="209.45454">
+    <path
+        android:strokeWidth="1"
+        android:pathData="M306,83c-5.52,0 -10,4.48 -10,10s4.48,10 10,10c5.52,0 10,-4.48 10,-10S311.52,83 306,83z"
+        android:fillColor="#fff"
+        android:strokeColor="#fff"/>
+    <path
+        android:strokeWidth="1"
+        android:pathData="M206,83c-5.52,0 -10,4.48 -10,10s4.48,10 10,10s10,-4.48 10,-10S211.52,83 206,83z"
+        android:fillColor="#fff"
+        android:strokeColor="#fff"/>
+    <path
+        android:strokeWidth="1"
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+        android:strokeWidth="1"
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+        android:fillColor="#fff"
+        android:strokeColor="#fff"/>
+  </group>
+</vector>
--- a/app/src/main/res/drawable/ic_star_border_gold.xml
+++ b/app/src/main/res/drawable/ic_star_border_gold.xml
@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="@color/gold"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M22,9.24l-7.19,-0.62L12,2 9.19,8.63 2,9.24l5.46,4.73L5.82,21 12,17.27 18.18,21l-1.63,-7.03L22,9.24zM12,15.4l-3.76,2.27 1,-4.28 -3.32,-2.88 4.38,-0.38L12,6.1l1.71,4.04 4.38,0.38 -3.32,2.88 1,4.28L12,15.4z"/>
+</vector>
--- a/app/src/main/res/drawable/ic_star_border_silver.xml
+++ b/app/src/main/res/drawable/ic_star_border_silver.xml
@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="@color/silver"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M22,9.24l-7.19,-0.62L12,2 9.19,8.63 2,9.24l5.46,4.73L5.82,21 12,17.27 18.18,21l-1.63,-7.03L22,9.24zM12,15.4l-3.76,2.27 1,-4.28 -3.32,-2.88 4.38,-0.38L12,6.1l1.71,4.04 4.38,0.38 -3.32,2.88 1,4.28L12,15.4z"/>
+</vector>
--- a/app/src/main/res/drawable/ic_star_gold.xml
+++ b/app/src/main/res/drawable/ic_star_gold.xml
@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="@color/gold"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M12,17.27L18.18,21l-1.64,-7.03L22,9.24l-7.19,-0.61L12,2 9.19,8.63 2,9.24l5.46,4.73L5.82,21z"/>
+</vector>
--- a/app/src/main/res/drawable/ic_star_silver.xml
+++ b/app/src/main/res/drawable/ic_star_silver.xml
@@ -0,0 +1,5 @@
+<vector android:height="24dp" android:tint="@color/silver"
+    android:viewportHeight="24.0" android:viewportWidth="24.0"
+    android:width="24dp" xmlns:android="http://schemas.android.com/apk/res/android">
+    <path android:fillColor="#FF000000" android:pathData="M12,17.27L18.18,21l-1.64,-7.03L22,9.24l-7.19,-0.61L12,2 9.19,8.63 2,9.24l5.46,4.73L5.82,21z"/>
+</vector>
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".MainActivity">
+
+    <FrameLayout
+        android:id="@+id/fragment_holder"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>
--- a/app/src/main/res/layout/fragment_summary.xml
+++ b/app/src/main/res/layout/fragment_summary.xml
@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".fragments.SummaryFragment"
+    android:orientation="vertical">
+
+    <com.google.android.material.button.MaterialButton
+        android:id="@+id/retry"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="@string/retry"/>
+    <com.google.android.material.button.MaterialButton
+        android:id="@+id/exit"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="@string/to_main_menu"/>
+    <com.google.android.material.textview.MaterialTextView
+        android:id="@+id/time"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:textColor="@android:color/primary_text_light"
+        android:textSize="15sp"
+        android:textAlignment="center"/>
+
+</LinearLayout>
--- a/app/src/main/res/layout/fragment_task.xml
+++ b/app/src/main/res/layout/fragment_task.xml
@@ -0,0 +1,117 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    tools:context=".fragments.TaskFragment">
+
+
+    <TextView
+        android:id="@+id/name"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:textAppearance="@style/TextAppearance.MaterialComponents.Overline"
+        android:textAlignment="center"/>
+
+    <com.google.android.material.card.MaterialCardView
+        android:id="@+id/card"
+        android:layout_width="match_parent"
+        android:layout_height="100sp"
+        android:layout_margin="10sp"
+        android:layout_below="@id/name"
+        app:cardBackgroundColor="@color/colorPrimaryDark">
+        <TextView
+            android:id="@+id/question"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_vertical"
+            android:textColor="@android:color/primary_text_dark"
+            android:textSize="30sp"
+            android:textAlignment="center"/>
+    </com.google.android.material.card.MaterialCardView>
+
+    <TextView
+        android:id="@+id/time"
+        android:layout_below="@id/card"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:textAppearance="@style/TextAppearance.MaterialComponents.Body2"
+        android:textAlignment="center"/>
+    <TextView
+        android:id="@+id/question_count"
+        android:layout_below="@id/card"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:textAppearance="@style/TextAppearance.MaterialComponents.Body2"
+        android:layout_alignStart="@id/card"
+        android:layout_alignLeft="@id/card" />
+    <TextView
+        android:id="@+id/question_correct"
+        android:layout_below="@id/card"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:textAppearance="@style/TextAppearance.MaterialComponents.Body2"
+        android:layout_alignEnd="@id/card"
+        android:layout_alignRight="@id/card" />
+
+    <me.zhanghai.android.materialprogressbar.MaterialProgressBar
+        android:id="@+id/progress"
+        android:layout_width="match_parent"
+        android:layout_height="8dp"
+        android:layout_below="@id/time"
+        android:indeterminate="false"
+        app:mpb_progressStyle="horizontal"
+        android:background="@color/gold"
+        app:mpb_useIntrinsicPadding="false"
+        app:mpb_secondaryProgressTint="@color/silver"
+        app:mpb_progressTint="@color/bronze"
+        android:secondaryProgress="80"
+        android:progress="60"
+        style="@style/Widget.MaterialProgressBar.ProgressBar.Horizontal"
+        android:layout_alignStart="@id/card"
+        android:layout_alignLeft="@id/card"
+        android:layout_alignEnd="@id/card"
+        android:layout_alignRight="@id/card" />
+    <me.zhanghai.android.materialprogressbar.MaterialProgressBar
+        android:id="@+id/progress2"
+        android:layout_width="match_parent"
+        android:layout_height="8dp"
+        android:layout_below="@id/progress"
+        android:indeterminate="false"
+        app:mpb_progressStyle="horizontal"
+        android:background="@color/colorPrimaryLight"
+        app:mpb_useIntrinsicPadding="false"
+        android:secondaryProgress="100"
+        android:progress="0"
+        app:mpb_secondaryProgressTint="@color/colorPrimaryLight"
+        app:mpb_progressTint="@color/colorPrimary"
+        style="@style/Widget.MaterialProgressBar.ProgressBar.Horizontal"
+        android:layout_alignStart="@id/card"
+        android:layout_alignLeft="@id/card"
+        android:layout_alignEnd="@id/card"
+        android:layout_alignRight="@id/card" />
+
+    <TextView
+        android:id="@+id/answer"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_above="@id/keyboardview"
+        android:background="@color/colorPrimaryDark"
+        android:gravity="center"
+        android:text="@string/hello_blank_fragment"
+        android:textAppearance="@style/TextAppearance.AppCompat.Large" />
+
+    <de.sebse.mentalarithmetic.utils.BoardView xmlns:custom="http://schemas.android.com/apk/res/de.sebse.mentalarithmetic"
+        android:id="@+id/keyboardview"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_alignParentBottom="true"
+        android:layout_centerHorizontal="true"
+        android:focusable="true"
+        android:focusableInTouchMode="true"
+        custom:showText="true"
+        custom:labelPosition="left"
+        />
+
+</RelativeLayout>
--- a/app/src/main/res/layout/fragment_taskitem.xml
+++ b/app/src/main/res/layout/fragment_taskitem.xml
@@ -0,0 +1,78 @@
+<?xml version="1.0" encoding="utf-8"?>
+<com.google.android.material.card.MaterialCardView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_margin="@dimen/default_gap"
+    android:layout_marginBottom="0dp">
+    <RelativeLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_margin="@dimen/text_margin">
+
+        <com.google.android.material.textview.MaterialTextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:id="@+id/personal_time"
+            android:layout_alignTop="@id/content"
+            android:layout_toLeftOf="@id/silver_time"
+            android:layout_toStartOf="@id/silver_time"
+            tools:ignore="RelativeOverlap" />
+        <com.google.android.material.textview.MaterialTextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:id="@+id/silver_time"
+            android:drawableStart="@drawable/ic_star_border_silver"
+            android:drawableLeft="@drawable/ic_star_border_silver"
+            android:layout_alignTop="@id/content"
+            android:layout_toLeftOf="@id/gold_time"
+            android:layout_toStartOf="@id/gold_time"
+            tools:ignore="RelativeOverlap" />
+        <com.google.android.material.textview.MaterialTextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:id="@+id/gold_time"
+            android:drawableStart="@drawable/ic_star_border_gold"
+            android:drawableLeft="@drawable/ic_star_border_gold"
+            android:layout_alignTop="@id/content"
+            android:layout_alignEnd="@id/progress"
+            android:layout_alignRight="@id/progress" />
+
+        <com.google.android.material.textview.MaterialTextView
+            android:id="@+id/content"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textAppearance="@style/TextAppearance.MaterialComponents.Body1"
+            tools:text="Test Task Name" />
+        <me.zhanghai.android.materialprogressbar.MaterialProgressBar
+            android:id="@+id/progress"
+            android:layout_width="match_parent"
+            android:layout_height="4dp"
+            android:layout_below="@id/content"
+            android:indeterminate="false"
+            app:mpb_progressStyle="horizontal"
+            android:background="@color/gold"
+            app:mpb_useIntrinsicPadding="false"
+            app:mpb_secondaryProgressTint="@color/silver"
+            app:mpb_progressTint="@color/bronze"
+            android:secondaryProgress="80"
+            android:progress="60"
+            style="@style/Widget.MaterialProgressBar.ProgressBar.Horizontal" />
+        <me.zhanghai.android.materialprogressbar.MaterialProgressBar
+            android:id="@+id/progress2"
+            android:layout_width="match_parent"
+            android:layout_height="4dp"
+            android:layout_below="@id/progress"
+            android:indeterminate="false"
+            app:mpb_progressStyle="horizontal"
+            android:background="@color/colorPrimaryLight"
+            app:mpb_useIntrinsicPadding="false"
+            android:secondaryProgress="100"
+            android:progress="0"
+            app:mpb_secondaryProgressTint="@color/colorPrimaryLight"
+            app:mpb_progressTint="@color/colorPrimary"
+            style="@style/Widget.MaterialProgressBar.ProgressBar.Horizontal" />
+    </RelativeLayout>
+
+</com.google.android.material.card.MaterialCardView>
--- a/app/src/main/res/layout/fragment_taskitem_list.xml
+++ b/app/src/main/res/layout/fragment_taskitem_list.xml
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.recyclerview.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/list"
+    android:name="de.sebse.mentalarithmetic.fragments.TaskItemFragment"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:layout_marginLeft="16dp"
+    android:layout_marginRight="16dp"
+    app:layoutManager="LinearLayoutManager"
+    tools:context=".fragments.TaskItemFragment"
+    tools:listitem="@layout/fragment_taskitem" />
--- a/app/src/main/res/layout/fragment_taskitem_pager.xml
+++ b/app/src/main/res/layout/fragment_taskitem_pager.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+    <me.relex.circleindicator.CircleIndicator3
+        android:id="@+id/titlestrip"
+        android:layout_width="match_parent"
+        android:layout_height="16dp"
+        android:background="@color/colorAccent"/>
+    <androidx.viewpager2.widget.ViewPager2
+        android:id="@+id/pager"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent" />
+</LinearLayout>
--- a/app/src/main/res/layout/fragment_tip.xml
+++ b/app/src/main/res/layout/fragment_tip.xml
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    tools:context=".fragments.TaskFragment">
+
+
+    <TextView
+        android:id="@+id/name"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:textAppearance="@style/TextAppearance.MaterialComponents.Body1"
+        />
+
+</RelativeLayout>
--- a/app/src/main/res/layout/fragment_tipitem.xml
+++ b/app/src/main/res/layout/fragment_tipitem.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?>
+<com.google.android.material.card.MaterialCardView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_margin="@dimen/default_gap"
+    android:layout_marginBottom="0dp">
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_margin="@dimen/text_margin"
+        android:orientation="vertical">
+
+        <com.google.android.material.textview.MaterialTextView
+            android:id="@+id/content"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textAppearance="@style/TextAppearance.MaterialComponents.Body1"
+            tools:text="Test Task Name" />
+
+        <com.google.android.material.textview.MaterialTextView
+            android:id="@+id/description"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textAppearance="@style/TextAppearance.MaterialComponents.Body2"
+            tools:text="Test Task Name" />
+    </LinearLayout>
+
+</com.google.android.material.card.MaterialCardView>
--- a/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
+++ b/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
+++ b/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background"/>
+    <foreground android:drawable="@drawable/ic_launcher_foreground"/>
+</adaptive-icon>
--- a/app/src/main/res/mipmap-hdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-hdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-hdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-mdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-mdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-mdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-xhdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-xhdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-xxhdpi/ic_launcher_round.png
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png
--- a/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.png
+++ b/app/src/main/res/mipmap-xxxhdpi/ic_launcher_round.png
--- a/app/src/main/res/values/attrs.xml
+++ b/app/src/main/res/values/attrs.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <declare-styleable name="BoardView">
+        <attr name="showText" format="boolean" />
+        <attr name="labelPosition" format="enum">
+            <enum name="left" value="0"/>
+            <enum name="right" value="1"/>
+        </attr>
+    </declare-styleable>
+</resources>
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="colorPrimary">#008577</color>
+    <color name="colorPrimaryDark">#00574B</color>
+    <color name="colorPrimaryLight">#5CB1A8</color>
+    <color name="colorAccent">#D81B60</color>
+    <color name="gold">#D4AF37</color>
+    <color name="silver">#ACACAC</color>
+    <color name="bronze">#88540B</color>
+</resources>
--- a/app/src/main/res/values/dimens.xml
+++ b/app/src/main/res/values/dimens.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <dimen name="text_margin">16dp</dimen>
+</resources>
--- a/app/src/main/res/values/ic_launcher_background.xml
+++ b/app/src/main/res/values/ic_launcher_background.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="ic_launcher_background">#000064</color>
+</resources>
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -0,0 +1,34 @@
+<resources>
+    <string name="app_name">Mental Arithmetic</string>
+
+    <string name="hello_blank_fragment">Hello blank fragment</string>
+    <string name="even">even</string>
+    <string name="odd">odd</string>
+    <string name="retry">Retry</string>
+    <string name="to_main_menu">To Main Menu</string>
+    <string name="category_basic">Basic</string>
+    <string name="sunday">Sunday</string>
+    <string name="monday">Monday</string>
+    <string name="tuesday">Tuesday</string>
+    <string name="wednesday">Wednesday</string>
+    <string name="thursday">Thursday</string>
+    <string name="friday">Friday</string>
+    <string name="saturday">Saturday</string>
+    <string name="january">January</string>
+    <string name="february">February</string>
+    <string name="march">March</string>
+    <string name="april">April</string>
+    <string name="may">May</string>
+    <string name="june">June</string>
+    <string name="july">July</string>
+    <string name="august">August</string>
+    <string name="september">September</string>
+    <string name="october">October</string>
+    <string name="november">November</string>
+    <string name="december">December</string>
+    <string name="no">No</string>
+    <string name="yes">Yes</string>
+    <string name="question_count">Question Count: %1$d</string>
+    <string name="question_currect">%1$d / %2$d</string>
+    <string name="time">%1$d.%2$03d</string>
+</resources>
--- a/app/src/main/res/values/strings_tasks.xml
+++ b/app/src/main/res/values/strings_tasks.xml
@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="task_01_01_name">Even-Odd</string>
+    <string name="task_01_01_desc">Let\'s first train our reaction time!</string>
+    <string name="task_01_02_name">Tiny Addition 1</string>
+    <string name="task_01_02_desc">Train addition pairs</string>
+    <string name="task_01_03_name">Tiny Addition 2</string>
+    <string name="task_01_03_desc">Train addition pairs with carry over</string>
+    <string name="task_01_04_name">Larger numbers</string>
+    <string name="task_01_04_desc">Let\'s get large and add bigger (but easy) numbers!</string>
+    <string name="task_01_05_name">Addition</string>
+    <string name="task_01_05_desc">Add 2-digit numbers</string>
+
+    <string name="task_02_01_name">Week day codes</string>
+    <string name="task_02_01_desc">Each week day is assigned to a specific code</string>
+    <string name="task_02_02_name">Month codes: Jan - Mar</string>
+    <string name="task_02_02_desc">Learn the first 3 month codes!</string>
+    <string name="task_02_03_name">Month codes: Apr - Jun</string>
+    <string name="task_02_03_desc">Learn the next 3 month codes!</string>
+    <string name="task_02_04_name">Month codes: Jan - Jun</string>
+    <string name="task_02_04_desc">Show what you have learned so far!</string>
+    <string name="task_02_05_name">Month codes: Jul - Sep</string>
+    <string name="task_02_05_desc">Learn the month codes 7 to 9! Nearly!</string>
+    <string name="task_02_06_name">Month codes: Oct - Dec</string>
+    <string name="task_02_06_desc">Learn the last 3 month codes!</string>
+    <string name="task_02_07_name">Month codes: Jul - Dec</string>
+    <string name="task_02_07_desc">Are you ready for the ultimate test?</string>
+    <string name="task_02_08_name">Month codes</string>
+    <string name="task_02_08_desc">Now combine all your knowledge!</string>
+    <string name="task_02_09_name">Day code</string>
+    <string name="task_02_09_desc">What is the code of the day?</string>
+    <string name="task_02_10_name">Year code 1</string>
+    <string name="task_02_10_desc">Start simple with the first step only</string>
+    <string name="task_02_11_name">Year code 2</string>
+    <string name="task_02_11_desc">Getting  more complicated</string>
+    <string name="task_02_12_name">Year code 3</string>
+    <string name="task_02_12_desc">And even more!</string>
+    <string name="task_02_13_name">Year code 4</string>
+    <string name="task_02_13_desc">And now the complete calculation!</string>
+    <string name="task_02_14_name">Year code 5</string>
+    <string name="task_02_14_desc">What is the correct year code for the last 2 digits</string>
+    <string name="task_02_15_name">Century code</string>
+    <string name="task_02_15_desc">Answer with the correct century code 0, 2, 4 or 6</string>
+    <string name="task_02_16_name">Leap Year</string>
+    <string name="task_02_16_desc">Check if the year is a leap year</string>
+</resources>
--- a/app/src/main/res/values/strings_tips.xml
+++ b/app/src/main/res/values/strings_tips.xml
@@ -0,0 +1,60 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="tip_01_01_name">Welcome!</string>
+    <string name="tip_01_01_desc">Introduction</string>
+    <string name="tip_01_01_html"><![CDATA[ <h1>Introduction</h1>This is <b>pretty</b> <img src="ic_star_gold" />cool stuff! ]]></string>
+    <string name="tip_02_01_name">Week Day Calculation</string>
+    <string name="tip_02_01_desc">Introduction</string>
+    <string name="tip_02_01_html"><![CDATA[ <h1>Week Day Calculation</h1> Week days for each dayx can be calculated. We calculate a "day code", a "month code" and a "year code".<br/><br/> ]]></string>
+    <string name="tip_02_02_name">Month Codes</string>
+    <string name="tip_02_02_desc">A list of each month code</string>
+    <string name="tip_02_02_html"><![CDATA[ <h1>Month Codes</h1> Month codes are the only number you really have to learn. Here is a list with every code:<br/><ul>
+    <li>January: <b>0</b></li>
+    <li>February: <b>3</b></li>
+    <li>March: <b>3</b></li>
+    <li>April: <b>6</b></li>
+    <li>May: <b>1</b></li>
+    <li>June: <b>4</b></li>
+    <li>July: <b>6</b></li>
+    <li>August: <b>2</b></li>
+    <li>September: <b>5</b></li>
+    <li>October: <b>0</b></li>
+    <li>November: <b>3</b></li>
+    <li>December: <b>5</b></li>
+    </ul>
+]]></string>
+    <string name="tip_02_03_name">Day Codes</string>
+    <string name="tip_02_03_desc">How to calculate the date codes</string>
+    <string name="tip_02_03_html"><![CDATA[ <h1>Day Codes</h1>
+    This part is relatively simple. The day code is the day of the month modulo 7. "Modulo" is the remainder when dividing by 7, as explained in the following examples.<br/><ul>
+    <li>0 mod 7 = 0</li>
+    <li>5 mod 7 = 5</li>
+    <li>7 mod 7 = 0</li>
+    <li>8 mod 7 = 1</li>
+    <li>14 mod 7 = 0</li>
+    <li>18 mod 7 = 4</li>
+    </ul>
+]]></string>
+    <string name="tip_02_04_name">Year Codes</string>
+    <string name="tip_02_04_desc">How to calculate the year codes</string>
+    <string name="tip_02_04_html"><![CDATA[ <h1>Year Codes</h1>
+    Now it gets a bit more complicated, but don\'t worry: We break it down into small pieces and learn step by step.
+
+<h2> division into century and year</h2>
+Let\'s take the year 2013 as an example: In the following we will name the front two digits, "20", the century and the back two digits, "13", the year.
+
+<h2>The year code</h2>
+
+TL;DR: the formula is: (YY + (YY div 4)) mod 7
+
+<ol>
+<li> dividing the year by 4 and ignoring the rest: 13 div 4 = (<b>3</b>*4 + 1) div 4 = 3</li>
+<li>Totalize the last result with the year: 13 + <b>3</b> = 16</li>
+<li> Divide the result by 7 and select the rest: 16 mod 7 = (2*7 + <b>2</b>) mod 7 = 2</li>
+</ol>
+
+The year code for 13 is 2.
+
+Translated with www.DeepL.com/Translator (free version)
+]]></string>
+</resources>
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -0,0 +1,15 @@
+<resources>
+
+    <!-- Base application theme. -->
+    <style name="AppTheme" parent="Theme.MaterialComponents.DayNight.DarkActionBar">
+        <!-- Customize your theme here. -->
+        <item name="colorPrimary">@color/colorPrimary</item>
+        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
+        <item name="colorAccent">@color/colorAccent</item>
+    </style>
+
+    <style name="ShapeAppearance.MaterialComponents.SmallComponent">
+        <item name="cornerSize">10dp</item>
+    </style>
+
+</resources>
--- a/app/src/main/res/xml/keyboard_dec7.xml
+++ b/app/src/main/res/xml/keyboard_dec7.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Board>
+    <Row>
+        <Key codes="4" keyLabel="4"/>
+        <Key codes="5" keyLabel="5"/>
+        <Key codes="6" keyLabel="6"/>
+    </Row>
+    <Row>
+        <Key codes="1" keyLabel="1"/>
+        <Key codes="2" keyLabel="2"/>
+        <Key codes="3" keyLabel="3"/>
+    </Row>
+    <Row>
+        <Gap/>
+        <Key codes="0" keyLabel="0"/>
+        <Gap/>
+    </Row>
+</Board>
--- a/app/src/main/res/xml/keyboard_dec7_multi.xml
+++ b/app/src/main/res/xml/keyboard_dec7_multi.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Board>
+    <Row>
+        <Key codes="7" keyLabel="7"/>
+        <Key codes="8" keyLabel="8"/>
+        <Key codes="9" keyLabel="9"/>
+    </Row>
+    <Row>
+        <Key codes="4" keyLabel="4"/>
+        <Key codes="5" keyLabel="5"/>
+        <Key codes="6" keyLabel="6"/>
+    </Row>
+    <Row>
+        <Key codes="1" keyLabel="1"/>
+        <Key codes="2" keyLabel="2"/>
+        <Key codes="3" keyLabel="3"/>
+    </Row>
+    <Row>
+        <Key codes="-1" keyIcon="@drawable/ic_backspace"/>
+        <Key codes="0" keyLabel="0"/>
+        <Key codes="-2" keyLabel="ENTER"/>
+    </Row>
+</Board>
--- a/app/src/main/res/xml/keyboard_decimal.xml
+++ b/app/src/main/res/xml/keyboard_decimal.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Board>
+    <Row>
+        <Key codes="7" keyLabel="7"/>
+        <Key codes="8" keyLabel="8"/>
+        <Key codes="9" keyLabel="9"/>
+    </Row>
+    <Row>
+        <Key codes="4" keyLabel="4"/>
+        <Key codes="5" keyLabel="5"/>
+        <Key codes="6" keyLabel="6"/>
+    </Row>
+    <Row>
+        <Key codes="1" keyLabel="1"/>
+        <Key codes="2" keyLabel="2"/>
+        <Key codes="3" keyLabel="3"/>
+    </Row>
+    <Row>
+        <Gap/>
+        <Key codes="0" keyLabel="0"/>
+        <Gap/>
+    </Row>
+</Board>
--- a/app/src/main/res/xml/keyboard_decimal_multi.xml
+++ b/app/src/main/res/xml/keyboard_decimal_multi.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Board>
+    <Row>
+        <Key codes="7" keyLabel="7"/>
+        <Key codes="8" keyLabel="8"/>
+        <Key codes="9" keyLabel="9"/>
+    </Row>
+    <Row>
+        <Key codes="4" keyLabel="4"/>
+        <Key codes="5" keyLabel="5"/>
+        <Key codes="6" keyLabel="6"/>
+    </Row>
+    <Row>
+        <Key codes="1" keyLabel="1"/>
+        <Key codes="2" keyLabel="2"/>
+        <Key codes="3" keyLabel="3"/>
+    </Row>
+    <Row>
+        <Key codes="-1" keyIcon="@drawable/ic_backspace"/>
+        <Key codes="0" keyLabel="0"/>
+        <Key codes="-2" keyLabel="ENTER"/>
+    </Row>
+</Board>
--- a/app/src/main/res/xml/keyboard_odd.xml
+++ b/app/src/main/res/xml/keyboard_odd.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Board>
+    <Row>
+        <Key codes="0" keyLabel="Even"/>
+        <Key codes="1" keyLabel="Odd"/>
+    </Row>
+</Board>
--- a/app/src/main/res/xml/keyboard_yes_no.xml
+++ b/app/src/main/res/xml/keyboard_yes_no.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Board>
+    <Row>
+        <Key codes="0" keyLabel="No"/>
+        <Key codes="1" keyLabel="Yes"/>
+    </Row>
+</Board>
--- a/app/src/test/java/de/sebse/mentalarithmetic/ExampleUnitTest.kt
+++ b/app/src/test/java/de/sebse/mentalarithmetic/ExampleUnitTest.kt
@@ -0,0 +1,17 @@
+package de.sebse.mentalarithmetic
+
+import org.junit.Test
+
+import org.junit.Assert.*
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * See [testing documentation](http://d.android.com/tools/testing).
+ */
+class ExampleUnitTest {
+    @Test
+    fun addition_isCorrect() {
+        assertEquals(4, 2 + 2)
+    }
+}