Initial commit for assignment 09

.gitignore

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+*.iml
+.gradle
+/local.properties
+/.idea/caches
+/.idea/libraries
+/.idea/modules.xml
+/.idea/workspace.xml
+/.idea/navEditor.xml
+/.idea/assetWizardSettings.xml
+.DS_Store
+/build
+/captures
+.externalNativeBuild
+.cxx
+local.properties
+
+# Gradle files
+.gradle/
+build/
+
+# Local configuration file (sdk path, etc)
+local.properties
+
+# Log/OS Files
+*.log
+
+# Android Studio generated files and folders
+captures/
+.externalNativeBuild/
+.cxx/
+*.apk
+output.json
+
+# IntelliJ
+*.iml
+.idea/
+misc.xml
+deploymentTargetDropDown.xml
+render.experimental.xml
+
+# Keystore files
+*.jks
+*.keystore
+
+# Google Services (e.g. APIs or Firebase)
+google-services.json
+
+# Android Profiling
+*.hprof

app/.gitignore

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+/build

app/build.gradle

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+plugins {
+    id 'com.android.application'
+    id 'org.jetbrains.kotlin.android'
+}
+
+android {
+    namespace 'de.luh.hci.mi.experiencesampling'
+    compileSdk 33
+
+    defaultConfig {
+        applicationId "de.luh.hci.mi.experiencesampling"
+        minSdk 27
+        targetSdk 33
+        versionCode 1
+        versionName "1.0"
+
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+        vectorDrawables {
+            useSupportLibrary true
+        }
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+    }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+    kotlinOptions {
+        jvmTarget = '1.8'
+    }
+    buildFeatures {
+        compose true
+    }
+    composeOptions {
+        kotlinCompilerExtensionVersion '1.3.2'
+    }
+    packagingOptions {
+        resources {
+            excludes += '/META-INF/{AL2.0,LGPL2.1}'
+        }
+    }
+}
+
+dependencies {
+
+    implementation 'androidx.core:core-ktx:1.8.0'
+    implementation platform('org.jetbrains.kotlin:kotlin-bom:1.8.0')
+    implementation 'androidx.lifecycle:lifecycle-runtime-ktx:2.3.1'
+    implementation 'androidx.activity:activity-compose:1.5.1'
+    implementation platform('androidx.compose:compose-bom:2022.10.00')
+    implementation 'androidx.compose.ui:ui'
+    implementation 'androidx.compose.ui:ui-graphics'
+    implementation 'androidx.compose.ui:ui-tooling-preview'
+    implementation 'androidx.compose.material3:material3'
+    testImplementation 'junit:junit:4.13.2'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
+    androidTestImplementation platform('androidx.compose:compose-bom:2022.10.00')
+    androidTestImplementation 'androidx.compose.ui:ui-test-junit4'
+    debugImplementation 'androidx.compose.ui:ui-tooling'
+    debugImplementation 'androidx.compose.ui:ui-test-manifest'
+
+    implementation "androidx.lifecycle:lifecycle-viewmodel-compose:2.6.1"
+    implementation "androidx.navigation:navigation-compose:2.7.0-alpha01"
+}

app/proguard-rules.pro

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+# 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

app/src/androidTest/java/de/luh/hci/mi/experiencesampling/ExampleInstrumentedTest.kt

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+package de.luh.hci.mi.experiencesampling
+
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.platform.app.InstrumentationRegistry
+import org.junit.Assert.*
+import org.junit.Test
+import org.junit.runner.RunWith
+
+/**
+ * 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.luh.hci.mi.experiencesampling", appContext.packageName)
+    }
+}

app/src/main/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
+    <uses-permission android:name="android.permission.SCHEDULE_EXACT_ALARM" />
+    <uses-permission android:name="android.permission.VIBRATE" />
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.WAKE_LOCK" />
+
+    <application
+        android:name=".ExperienceSampling"
+        android:allowBackup="true"
+        android:dataExtractionRules="@xml/data_extraction_rules"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:theme="@style/Theme.ExperienceSampling">
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:theme="@style/Theme.ExperienceSampling">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+        <activity
+            android:name=".notifications.SamplingActivity"
+            android:launchMode="singleTask"
+            android:taskAffinity=""
+            android:excludeFromRecents="true"
+            android:theme="@style/Theme.ExperienceSampling" />
+        <receiver
+            android:process=":remote"
+            android:name=".notifications.NotificationTrigger" />
+    </application>
+
+</manifest>

app/src/main/java/de/luh/hci/mi/experiencesampling/ExperienceSampling.kt

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+package de.luh.hci.mi.experiencesampling
+
+import android.app.AlarmManager
+import android.app.Application
+import android.app.PendingIntent
+import android.content.Context
+import android.content.Intent
+import android.util.Log
+import androidx.compose.runtime.mutableStateOf
+import de.luh.hci.mi.experiencesampling.data.CouchDB
+import de.luh.hci.mi.experiencesampling.data.Repository
+import de.luh.hci.mi.experiencesampling.data.RepositoryImpl
+import de.luh.hci.mi.experiencesampling.notifications.NotificationTrigger
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+
+// Time between notifications in milliseconds.
+const val samplingInterval = 10000L // milliseconds
+
+// Unique identifier for experimenter. Used to distinguish between entries in database.
+const val experimenter = "2386452183276023461634920"
+
+// The application instance exists as long as the app executes and is therefore used for app-wide
+// data that is used in activities.
+class ExperienceSampling : Application() {
+    // officially: use Dagger-Hilt dependency injection, rather than manual dependency injection
+    // https://developer.android.com/training/dependency-injection
+    // https://developer.android.com/training/dependency-injection/manual
+
+    private lateinit var remoteDb: CouchDB
+    lateinit var repository: Repository
+        private set
+
+    // Coroutine scope for submitting data to server. Continues even when navigating away from UI.
+    val applicationScope = CoroutineScope(SupervisorJob() + Dispatchers.Main)
+
+    override fun onCreate() {
+        super.onCreate()
+        remoteDb = CouchDB("https://couchdb.hci.uni-hannover.de/mobint/")
+        repository = RepositoryImpl(applicationContext, remoteDb)
+    }
+
+    // Whether or not periodic experience sampling is on.
+    val periodicSampling = mutableStateOf(false)
+
+    // Schedules the next notification delay ms from now.
+    fun scheduleNextNotification(delay: Long) {
+        val am = getSystemService(Context.ALARM_SERVICE) as AlarmManager
+        val i = Intent(this, NotificationTrigger::class.java)
+        val pi = PendingIntent.getBroadcast(this, 0, i, PendingIntent.FLAG_MUTABLE)
+        am.setExactAndAllowWhileIdle(
+            AlarmManager.RTC_WAKEUP,
+            System.currentTimeMillis() + delay,
+            pi
+        )
+    }
+
+    // Cancels any registered notification.
+    fun cancelNotification() {
+        val am = getSystemService(Context.ALARM_SERVICE) as AlarmManager
+        val i = Intent(this, NotificationTrigger::class.java)
+        val pi = PendingIntent.getBroadcast(this, 0, i, PendingIntent.FLAG_MUTABLE)
+        am.cancel(pi)
+    }
+
+    // Logs a debug message.
+    private fun log(msg: String) {
+        Log.d(this.javaClass.simpleName, msg)
+    }
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/MainActivity.kt

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+package de.luh.hci.mi.experiencesampling
+
+import android.os.Bundle
+import android.util.Log
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.lifecycle.viewmodel.compose.viewModel
+import androidx.navigation.compose.NavHost
+import androidx.navigation.compose.composable
+import androidx.navigation.compose.rememberNavController
+import de.luh.hci.mi.experiencesampling.ui.sampling.SamplingScreen
+import de.luh.hci.mi.experiencesampling.ui.sampling.SamplingViewModel
+import de.luh.hci.mi.experiencesampling.ui.start.StartScreen
+import de.luh.hci.mi.experiencesampling.ui.start.StartViewModel
+import de.luh.hci.mi.experiencesampling.ui.statistics.StatisticsScreen
+import de.luh.hci.mi.experiencesampling.ui.statistics.StatisticsViewModel
+import de.luh.hci.mi.experiencesampling.ui.theme.ExperienceSamplingTheme
+
+
+// The main activity sets the content root, which is a navigation graph. Each "composable" in the
+// navigation graph is a separate page/screen of the app.
+// https://developer.android.com/jetpack/compose/navigation
+// https://developer.android.com/guide/navigation/principles
+class MainActivity : ComponentActivity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        log("onCreate")
+        setContent {
+            ExperienceSamplingTheme {
+                // The NavController manages navigation in the navigation graph (e.g, back and up).
+                val navController = rememberNavController()
+                // The NavHost composable is a container for navigation destinations.
+                NavHost(
+                    navController = navController,
+                    startDestination = Routes.START
+                ) {
+                    // The NavGraph has a composable for each navigation destination.
+                    // Each destination is associated with a route (a string).
+                    // ViewModels can be scoped to navigation graphs.
+
+                    // navigation destination
+                    composable(route = Routes.START) {
+                        StartScreen(
+                            onNavigate = navController::navigate, // function used to navigate to another destination
+                            viewModel(factory = StartViewModel.Factory) // create view model (or get from cache)
+                        )
+                    }
+
+                    // navigation destination
+                    composable(route = Routes.STATISTICS) {
+                        StatisticsScreen(
+                            navigateBack = navController::popBackStack, // executed when save button is pressed
+                            viewModel(factory = StatisticsViewModel.Factory) // create view model (or get from cache)
+                        )
+                    }
+
+                    // navigation destination
+                    composable(route = Routes.SAMPLING) {
+                        SamplingScreen(
+                            navigateBack = navController::popBackStack, // executed when save button is pressed
+                            viewModel(factory = SamplingViewModel.Factory) // create view model (or get from cache)
+                        )
+                    }
+
+                }
+            }
+        }
+    }
+
+    // Logs a debug message.
+    private fun log(msg: String) {
+        Log.d(this.javaClass.simpleName, msg)
+    }
+
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/Routes.kt

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+package de.luh.hci.mi.experiencesampling
+
+// Each navigation destination (screen) has a "route" associated to it.
+object Routes {
+    const val START = "start"
+    const val STATISTICS = "statistics"
+    const val SAMPLING = "sampling"
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/data/CouchDB.kt

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+package de.luh.hci.mi.experiencesampling.data
+
+import android.util.Log
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import org.json.JSONObject
+import java.io.BufferedReader
+import java.io.BufferedWriter
+import java.io.InputStreamReader
+import java.io.OutputStreamWriter
+import java.net.HttpURLConnection
+import java.net.URL
+
+/**
+ * Stores and retrieves JSON documents on/from the DB server.
+ * http://couchdb.apache.org
+ * https://www.json.org/json-en.html
+ * http://developer.android.com/reference/org/json/JSONObject.html
+ */
+class CouchDB(private val dbUrl: String) {
+
+    // Gets a JSON object from the server given a resource path.
+    // Example path: _design/esm/_view/ctxt?key=%22Programmieren+1%22
+    // Throws an exception on failure.
+    suspend fun get(resourcePath: String): JSONObject =
+        withContext(Dispatchers.IO) {
+            Log.d(javaClass.simpleName, "get: " + Thread.currentThread().name)
+            // simulate delay
+            // delay(3000L)
+            val url = URL(dbUrl + resourcePath)
+            val con = url.openConnection() as HttpURLConnection
+            try {
+                val reader = BufferedReader(InputStreamReader(con.inputStream))
+                val obj = JSONObject(reader.readText())
+                reader.close()
+                return@withContext obj
+            } finally {
+                con.disconnect()
+            }
+        }
+
+    // Stores the given JSON object at the indicated location on the server.
+    // Returns the server's response. Throws an exception on failure.
+    suspend fun put(resourcePath: String, doc: JSONObject): JSONObject =
+        withContext(Dispatchers.IO) {
+            Log.d(javaClass.simpleName, "put: " + Thread.currentThread().name)
+            // simulate delay
+            // delay(7000L)
+            val url = URL(dbUrl + resourcePath)
+            val con = url.openConnection() as HttpURLConnection
+            try {
+                con.doOutput = true
+                con.requestMethod = "PUT"
+                con.setChunkedStreamingMode(0) // write in chunks
+                con.setRequestProperty("Content-type", "application/json")
+                con.setRequestProperty("Accept", "application/json")
+                val writer = BufferedWriter(OutputStreamWriter(con.outputStream))
+                writer.write(doc.toString())
+                writer.close()
+                val reader = BufferedReader(InputStreamReader(con.inputStream))
+                val obj = JSONObject(reader.readText())
+                reader.close()
+                return@withContext obj
+            } finally {
+                con.disconnect()
+            }
+        }
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/data/Rating.kt

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+package de.luh.hci.mi.experiencesampling.data
+
+// A questionnaire item.
+data class Item(
+    val title: String,
+    val question: String,
+    val negativeEnd: String,
+    val positiveEnd: String
+)
+
+// A rating associated with a questionnaire item.
+data class Rating(
+    val item: Item,
+    val value: Float
+)

app/src/main/java/de/luh/hci/mi/experiencesampling/data/Repository.kt

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+package de.luh.hci.mi.experiencesampling.data
+
+// A repository is an interface to (a category of) the app's data.
+// The repository interface isolates the data layer from the rest of the app.
+// https://developer.android.com/topic/architecture/data-layer
+// https://developer.android.com/codelabs/basic-android-kotlin-training-repository-pattern
+interface Repository {
+
+    // Contexts a user may be in.
+    fun getContexts(): List<String>
+
+    // Questionnaire items.
+    fun getItems(): List<Item>
+
+    // Submits the list of ratings. May throw an IOException.
+    suspend fun submitRatings(context: String, ratings: List<Rating>)
+
+    // Retrieves the ratings for the given context. May throw an IOException.
+    suspend fun getRatings(context: String): Map<Item, Float>
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/data/RepositoryImpl.kt

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+package de.luh.hci.mi.experiencesampling.data
+
+import android.content.Context
+import android.util.Log
+import de.luh.hci.mi.experiencesampling.R
+import de.luh.hci.mi.experiencesampling.experimenter
+import org.json.JSONObject
+import java.net.URLEncoder
+
+// Implementation of the repository interface. It relies on a database as a data source,
+// which is provided via the constructor (dependency injection).
+// https://developer.android.com/topic/architecture/data-layer
+// https://developer.android.com/codelabs/basic-android-kotlin-training-repository-pattern
+class RepositoryImpl(
+    context: Context, // application context (not the user's context)
+    private val db: CouchDB
+) : Repository {
+
+    // Fixed list of contexts a user may be in.
+    private val contexts = listOf(
+        context.getString(R.string.context_1),
+        context.getString(R.string.context_2),
+        context.getString(R.string.context_3)
+    )
+
+    // Fixed list of questionnaire items.
+    private val items = listOf(
+        Item(
+            context.getString(R.string.understanding),
+            context.getString(R.string.understanding_question),
+            context.getString(R.string.complicated),
+            context.getString(R.string.easy)
+        ),
+        Item(
+            context.getString(R.string.interest),
+            context.getString(R.string.interest_question),
+            context.getString(R.string.not_interesting),
+            context.getString(R.string.interesting)
+        ),
+        Item(
+            context.getString(R.string.lecturer),
+            context.getString(R.string.lecturer_question),
+            context.getString(R.string.boring),
+            context.getString(R.string.exciting)
+        ),
+        Item(
+            context.getString(R.string.slides),
+            context.getString(R.string.slides_question),
+            context.getString(R.string.obstructive),
+            context.getString(R.string.supportive)
+        ),
+    )
+
+    override fun getContexts(): List<String> {
+        return contexts
+    }
+
+    override fun getItems(): List<Item> {
+        return items
+    }
+
+    override suspend fun submitRatings(context: String, ratings: List<Rating>) {
+        Log.d(javaClass.simpleName, "submitRatings: " + Thread.currentThread().name)
+        // store in online database
+        // create JSON document and send to server
+        val obj = JSONObject()
+        // timestamp
+        val time = System.currentTimeMillis()
+        obj.put("time", time)
+        obj.put("experimenter", experimenter)
+        obj.put("context", context)
+        for (rating in ratings) {
+            obj.put(rating.item.title, rating.value)
+        }
+        Log.d(javaClass.simpleName, obj.toString())
+        val docId = "esm$time"
+        val response = db.put(docId, obj)
+        Log.d(javaClass.simpleName, response.toString())
+    }
+
+    /*
+    Example query:
+    https://couchdb.hci.uni-hannover.de/mobint/_design/esm/_view/ctxtexp?key=["Mobile Interaktion","MyExperimenterId"]
+
+    Example get response:
+    {"total_rows":8,"offset":0,"rows":[
+    {"id":"esm1686831673152","key":"Mensa","value":{"_id":"esm1686831673152","_rev":"1-dacc2a8f08698a838d291870f737f282","time":1686831673152,"experimenter":"MyExperimenterId","context":"Mensa","Mood":5,"Understanding":4,"Difficulty":3}},
+    {"id":"esm1686834330948","key":"Mensa","value":{"_id":"esm1686834330948","_rev":"1-bceece5c4ae08cdf34dd5f2f2ff0ee5a","time":1686834330948,"experimenter":"MyExperimenterId","context":"Mensa","Mood":1,"Understanding":1,"Difficulty":1}}
+    ]}
+    */
+
+    override suspend fun getRatings(context: String): Map<Item, Float> {
+        // query context for all experimenters
+        // val key = URLEncoder.encode("\"$context\"", "UTF-8")
+        // val query = "_design/esm/_view/ctxt?key=$key"
+
+        // query context for one experimenter only
+        val key = URLEncoder.encode("[\"$context\",\"$experimenter\"]", "UTF-8")
+        val query = "_design/esm/_view/ctxtexp?key=$key"
+        Log.d(javaClass.simpleName, query)
+        val obj = db.get(query)
+
+        // compute the average ratings per item from the set of retrieved values
+        val averageRatings: MutableMap<Item, Float> = mutableMapOf()
+        val rows = obj.getJSONArray("rows")
+        val n = rows.length()
+        if (n > 0) {
+            for (i in 0 until n) {
+                val row = rows.getJSONObject(i).getJSONObject("value")
+                Log.d(javaClass.simpleName, "row: $row")
+                for (item in getItems()) {
+                    val rating = row.getDouble(item.title).toFloat()
+                    val sum = averageRatings[item] ?: 0f
+                    averageRatings[item] = sum + rating
+                }
+            }
+            for (item in getItems()) {
+                val sum = averageRatings[item] ?: 0f
+                averageRatings[item] = sum / n
+            }
+        }
+        return averageRatings
+    }
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/notifications/NotificationTrigger.kt

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+package de.luh.hci.mi.experiencesampling.notifications
+
+import android.Manifest
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.PendingIntent
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.content.pm.PackageManager
+import android.graphics.Color
+import android.util.Log
+import androidx.core.app.ActivityCompat
+import androidx.core.app.NotificationCompat
+import androidx.core.app.NotificationManagerCompat
+import de.luh.hci.mi.experiencesampling.R
+
+// This component receives alarms and triggers a notification for each alarm.
+// The alarm is registered in ExperienceSampling::scheduleNextNotification.
+// https://developer.android.com/develop/ui/views/notifications
+class NotificationTrigger : BroadcastReceiver() {
+
+    // Theis broadcast receiver is registered to receive alarms.
+    override fun onReceive(context: Context, intent: Intent) {
+        showNotification(context)
+    }
+
+    // Notifications are posted on notification channels, so create one if needed.
+    private fun createNotificationChannel(context: Context) {
+        val channelId = context.getString(R.string.channel_id)
+        val notificationManager = NotificationManagerCompat.from(context)
+        var channel = notificationManager.getNotificationChannel(channelId)
+        log("channel: $channel")
+        if (channel == null) {
+            val name = context.getString(R.string.channel_name)
+            val description = context.getString(R.string.channel_description)
+            val importance = NotificationManager.IMPORTANCE_DEFAULT
+            channel = NotificationChannel(channelId, name, importance)
+            channel.description = description
+            channel.enableLights(true)
+            channel.lightColor = Color.RED
+            channel.enableVibration(true)
+            channel.vibrationPattern = longArrayOf(0, 200, 500, 400, 500, 400, 500, 200, 500)
+            notificationManager.createNotificationChannel(channel)
+        }
+    }
+
+    // Shows a notification. Clicking on the notification starts the sampling activity.
+    private fun showNotification(context: Context) {
+        createNotificationChannel(context)
+
+        val intent = Intent(context, SamplingActivity::class.java)
+        intent.action = Intent.ACTION_VIEW
+        intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
+        val pendingIntent: PendingIntent =
+            PendingIntent.getActivity(
+                context,
+                0,
+                intent,
+                PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
+            )
+
+        val channelId = context.getString(R.string.channel_id)
+        val builder = NotificationCompat.Builder(context, channelId)
+            .setSmallIcon(R.drawable.notification_icon)
+            .setContentTitle(context.getString(R.string.what_experience))
+            .setPriority(NotificationCompat.PRIORITY_DEFAULT)
+            .setContentIntent(pendingIntent) // fire this intent when the user taps the notification
+            .setAutoCancel(true) // remove the notification when the user taps it
+
+        // https://developer.android.com/training/permissions/requesting
+        val notificationManager = NotificationManagerCompat.from(context)
+        val permissionGranted = ActivityCompat.checkSelfPermission(
+            context,
+            Manifest.permission.POST_NOTIFICATIONS
+        ) == PackageManager.PERMISSION_GRANTED
+        log("permissionGranted: $permissionGranted")
+
+        notificationManager.notify(0, builder.build())
+    }
+
+    // Logs a debug message.
+    private fun log(msg: String) {
+        Log.d(this.javaClass.simpleName, msg)
+    }
+
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/notifications/SamplingActivity.kt

@@ -0,0 +1,34 @@
+package de.luh.hci.mi.experiencesampling.notifications
+
+import android.os.Bundle
+import android.util.Log
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.lifecycle.viewmodel.compose.viewModel
+import de.luh.hci.mi.experiencesampling.ui.sampling.SamplingScreen
+import de.luh.hci.mi.experiencesampling.ui.sampling.SamplingViewModel
+import de.luh.hci.mi.experiencesampling.ui.theme.ExperienceSamplingTheme
+
+// Shows the survey UI and submits the entered data to database server.
+// Started as a response to a notification.
+class SamplingActivity : ComponentActivity() {
+    // Associates the UI with the activity.
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        log("onCreate (response to notification)")
+        setContent {
+            ExperienceSamplingTheme {
+                SamplingScreen(
+                    navigateBack = this::finish, // end activity when input is done
+                    viewModel(factory = SamplingViewModel.Factory) // create view model (or get from cache)
+                )
+            }
+        }
+    }
+
+    // Logs a debug message.
+    private fun log(msg: String) {
+        Log.d(this.javaClass.simpleName, msg)
+    }
+
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/sampling/SamplingScreen.kt

@@ -0,0 +1,109 @@
+package de.luh.hci.mi.experiencesampling.ui.sampling
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Check
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.FloatingActionButton
+import androidx.compose.material3.Icon
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Slider
+import androidx.compose.material3.SnackbarHost
+import androidx.compose.material3.SnackbarHostState
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import de.luh.hci.mi.experiencesampling.R
+import de.luh.hci.mi.experiencesampling.ui.statistics.RadioGroup
+import kotlinx.coroutines.launch
+
+// UI for showing the questionnaire and taking an experience sample.
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun SamplingScreen(
+    navigateBack: () -> Unit, // navigate back to previous screen
+    viewModel: SamplingViewModel // the view model of this screen
+) {
+    // needed for showing a popup message
+    val snackbarHostState = remember {
+        SnackbarHostState()
+    }
+    // needed for showing a popup message
+    val scope = rememberCoroutineScope()
+    val thankYouMessage = stringResource(R.string.thank_you)
+
+    Scaffold(
+        snackbarHost = {
+            SnackbarHost(hostState = snackbarHostState)
+        },
+        floatingActionButton = {
+            FloatingActionButton(onClick = {
+                println("FAB: " + Thread.currentThread().name)
+                viewModel.submit()
+                scope.launch {
+                    println("sl: " + Thread.currentThread().name)
+                    snackbarHostState.showSnackbar(thankYouMessage)
+                    navigateBack()
+                }
+            }) {
+                Icon(
+                    imageVector = Icons.Default.Check,
+                    contentDescription = stringResource(R.string.submit)
+                )
+            }
+        }
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues),
+            horizontalAlignment = Alignment.CenterHorizontally
+        ) {
+            Spacer(Modifier.padding(8.dp))
+            Text(stringResource(R.string.context), fontSize = 24.sp)
+            Text(stringResource(R.string.context_question))
+            RadioGroup(viewModel.contexts, viewModel.selectedContext, viewModel::onContextSelected)
+
+            LazyColumn(
+                modifier = Modifier
+                    .padding(8.dp)
+                    .fillMaxWidth(),
+                horizontalAlignment = Alignment.CenterHorizontally
+            ) {
+                items(viewModel.items) { item ->
+                    Spacer(Modifier.padding(8.dp))
+                    Text(item.title, fontSize = 24.sp)
+                    if (item.question.isNotBlank()) {
+                        Text(item.question)
+                    }
+                    Row {
+                        Text(item.negativeEnd)
+                        Spacer(modifier = Modifier.weight(1f))
+                        Text(item.positiveEnd)
+                    }
+                    val sliderState = viewModel.sliderState(item)
+                    Slider(
+                        value = sliderState.value,
+                        onValueChange = { sliderState.value = it; println(it) },
+                        steps = 4,
+                        valueRange = 0f..5f
+                    )
+                }
+            }
+            Spacer(Modifier.padding(48.dp))
+        }
+    }
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/sampling/SamplingViewModel.kt

@@ -0,0 +1,102 @@
+package de.luh.hci.mi.experiencesampling.ui.sampling
+
+import android.util.Log
+import androidx.compose.runtime.MutableState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.ViewModelProvider.AndroidViewModelFactory.Companion.APPLICATION_KEY
+import androidx.lifecycle.viewmodel.initializer
+import androidx.lifecycle.viewmodel.viewModelFactory
+import de.luh.hci.mi.experiencesampling.ExperienceSampling
+import de.luh.hci.mi.experiencesampling.data.Item
+import de.luh.hci.mi.experiencesampling.data.Rating
+import de.luh.hci.mi.experiencesampling.data.Repository
+import de.luh.hci.mi.experiencesampling.samplingInterval
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
+import java.io.IOException
+import kotlin.math.roundToInt
+
+// ViewModel for the sampling screen.
+class SamplingViewModel constructor(
+    private val app: ExperienceSampling,
+    private val repository: Repository, // the underlying repository (data model)
+    private val applicationScope: CoroutineScope,
+) : ViewModel() {
+
+    // contexts from data model, const
+    val contexts = repository.getContexts()
+
+    // questionnaire items from data model, const
+    val items = repository.getItems()
+
+    // the currently selected context
+    var selectedContext by mutableStateOf(contexts[0])
+        private set
+
+    fun onContextSelected(context: String) {
+        selectedContext = context
+    }
+
+    // the current slider positions
+    private val sliderStates = mutableMapOf<Item, MutableState<Float>>()
+
+    fun sliderState(item: Item): MutableState<Float> {
+        var slider = sliderStates[item]
+        if (slider == null) {
+            slider = mutableFloatStateOf(0f)
+            sliderStates[item] = slider
+        }
+        return slider
+    }
+
+    // Submits the sample to the repository.
+    fun submit() {
+        // submit sample as a list of ratings
+        val sample = items.map {
+            Rating(it, sliderState(it).value.roundToInt().toFloat())
+        }
+        // https://medium.com/androiddevelopers/coroutines-patterns-for-work-that-shouldnt-be-cancelled-e26c40f142ad
+        // The submission should not be cancelled when the user navigates away from the screen.
+        // Thus an app-level coroutine scope is used here.
+        applicationScope.launch {
+            try {
+                println("applicationScope.launch: " + Thread.currentThread().name)
+                repository.submitRatings(selectedContext, sample)
+            } catch (ex: IOException) {
+                log("exception trying to submit: $ex")
+            }
+        }
+    }
+
+    // Called when this ViewModel is no longer used and will be destroyed. Can be used for cleanup.
+    override fun onCleared() {
+        log("onCleared")
+        // Navigating away from the sampling screen: Register next notification for sampling.
+        if (app.periodicSampling.value) {
+            app.scheduleNextNotification(samplingInterval)
+        }
+    }
+
+    // Logs a debug message.
+    private fun log(msg: String) {
+        Log.d(this.javaClass.simpleName, msg)
+    }
+
+    companion object {
+        // Companion object for creating the view model in the right lifecycle scope.
+        val Factory: ViewModelProvider.Factory = viewModelFactory {
+            initializer {
+                val app = this[APPLICATION_KEY] as ExperienceSampling
+                val repository = app.repository
+                val scope = app.applicationScope
+                SamplingViewModel(app, repository, scope)
+            }
+        }
+    }
+
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/start/StartScreen.kt

@@ -0,0 +1,52 @@
+package de.luh.hci.mi.experiencesampling.ui.start
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.unit.dp
+import de.luh.hci.mi.experiencesampling.R
+import de.luh.hci.mi.experiencesampling.Routes
+import de.luh.hci.mi.experiencesampling.ui.theme.Purple40
+import de.luh.hci.mi.experiencesampling.ui.theme.Purple80
+
+@Composable
+fun StartScreen(
+    onNavigate: (route: String) -> Unit, // used to navigate to another screen
+    viewModel: StartViewModel,
+) {
+    Column(
+        modifier = Modifier
+            .fillMaxSize()
+            .padding(8.dp),
+        horizontalAlignment = Alignment.CenterHorizontally
+    ) {
+        Spacer(Modifier.padding(24.dp))
+        Button(onClick = { onNavigate(Routes.SAMPLING) }) {
+            Text(stringResource(R.string.enter_experience_sample))
+        }
+        Spacer(Modifier.padding(24.dp))
+        Button(onClick = { onNavigate(Routes.STATISTICS) }) {
+            Text(stringResource(R.string.show_statistics))
+        }
+        Spacer(Modifier.padding(24.dp))
+        Button(
+            onClick = { viewModel.togglePeriodicSampling() },
+            colors = ButtonDefaults.buttonColors(if (viewModel.periodicSampling) Purple80 else Purple40)
+        ) {
+            if (viewModel.periodicSampling) {
+                Text(stringResource(R.string.stop_periodic_sampling))
+            } else {
+                Text(stringResource(R.string.start_periodic_sampling))
+            }
+        }
+        Spacer(Modifier.padding(24.dp))
+    }
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/start/StartViewModel.kt

@@ -0,0 +1,56 @@
+package de.luh.hci.mi.experiencesampling.ui.start
+
+import android.util.Log
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.setValue
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.ViewModelProvider.AndroidViewModelFactory.Companion.APPLICATION_KEY
+import androidx.lifecycle.viewmodel.initializer
+import androidx.lifecycle.viewmodel.viewModelFactory
+import de.luh.hci.mi.experiencesampling.ExperienceSampling
+import de.luh.hci.mi.experiencesampling.data.Repository
+import de.luh.hci.mi.experiencesampling.samplingInterval
+
+// ViewModel for the start screen.
+class StartViewModel constructor(
+    private val app: ExperienceSampling,
+    private val repository: Repository, // the underlying repository (data model)
+) : ViewModel() {
+
+    var periodicSampling by app.periodicSampling
+
+    fun togglePeriodicSampling() {
+        if (app.periodicSampling.value) {
+            log("stop sampling")
+            app.periodicSampling.value = false
+            app.cancelNotification()
+        } else {
+            log("start sampling")
+            app.scheduleNextNotification(samplingInterval)
+            app.periodicSampling.value = true
+        }
+    }
+
+    // Called when this ViewModel is no longer used and will be destroyed. Can be used for cleanup.
+    override fun onCleared() {
+        log("onCleared")
+    }
+
+    // Logs a debug message.
+    private fun log(msg: String) {
+        Log.d(this.javaClass.simpleName, msg)
+    }
+
+    companion object {
+        // Companion object for creating the view model in the right lifecycle scope.
+        val Factory: ViewModelProvider.Factory = viewModelFactory {
+            initializer {
+                val app = this[APPLICATION_KEY] as ExperienceSampling
+                val repository = app.repository
+                StartViewModel(app, repository)
+            }
+        }
+    }
+
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/statistics/StatisticsScreen.kt

@@ -0,0 +1,114 @@
+package de.luh.hci.mi.experiencesampling.ui.statistics
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.selection.selectable
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Star
+import androidx.compose.material3.Icon
+import androidx.compose.material3.RadioButton
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import de.luh.hci.mi.experiencesampling.ui.theme.Pink40
+import kotlin.math.roundToInt
+
+// The statistics screen shows average ratings for the selected context.
+@Composable
+fun StatisticsScreen(
+    navigateBack: () -> Unit,
+    viewModel: StatisticsViewModel
+) {
+    // todo: implement
+    LazyColumn {
+        items(viewModel.items) { item ->
+            Text(item.title)
+            val ratingState = viewModel.ratingState(item)
+            RatingBar(
+                rating = ratingState.value,
+                startLabel = item.negativeEnd,
+                endLabel = item.positiveEnd
+            )
+        }
+    }
+}
+
+@Composable
+fun RadioGroup(options: List<String>, selectedOption: String, onOptionSelected: (String) -> Unit) {
+    Column(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(8.dp),
+        horizontalAlignment = Alignment.CenterHorizontally
+    ) {
+        options.forEach { option ->
+            Row(
+                Modifier
+                    .fillMaxWidth()
+                    .selectable(
+                        selected = (option == selectedOption),
+                        onClick = { onOptionSelected(option) }
+                    ),
+                verticalAlignment = Alignment.CenterVertically
+            ) {
+                RadioButton(
+                    selected = (option == selectedOption),
+                    onClick = { onOptionSelected(option) }
+                )
+                Text(text = option)
+            }
+        }
+    }
+}
+
+@Composable
+fun RatingBar(
+    modifier: Modifier = Modifier,
+    rating: Float = 0f,
+    stars: Int = 5,
+    color: Color = Pink40,
+    startLabel: String = "",
+    endLabel: String = ""
+) {
+    assert(stars in 0..10)
+    assert(rating in 0f..10f)
+    assert(rating <= stars)
+    val ratingStars = rating.roundToInt()
+    val restStars = stars - ratingStars
+    Column(horizontalAlignment = Alignment.CenterHorizontally) {
+        if (startLabel.isNotBlank() || endLabel.isNotBlank()) {
+            Text("(%.1f)".format(rating), modifier = modifier.padding(start = 8.dp))
+        }
+        Row(
+            modifier = modifier,
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            Text(startLabel, modifier = modifier.padding(end = 8.dp))
+            repeat(ratingStars) {
+                Icon(imageVector = Icons.Filled.Star, contentDescription = null, tint = color)
+            }
+            repeat(restStars) {
+                Icon(
+                    imageVector = Icons.Filled.Star,
+                    contentDescription = null,
+                    tint = Color.LightGray
+                )
+            }
+            Text(endLabel, modifier = modifier.padding(start = 8.dp))
+        }
+    }
+}
+
+@Preview
+@Composable
+fun RatingPreview() {
+    RatingBar(rating = 2.5f, startLabel = "very bad", endLabel = "very good")
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/statistics/StatisticsViewModel.kt

@@ -0,0 +1,102 @@
+package de.luh.hci.mi.experiencesampling.ui.statistics
+
+import android.util.Log
+import androidx.compose.runtime.MutableState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.ViewModelProvider.AndroidViewModelFactory.Companion.APPLICATION_KEY
+import androidx.lifecycle.viewModelScope
+import androidx.lifecycle.viewmodel.initializer
+import androidx.lifecycle.viewmodel.viewModelFactory
+import de.luh.hci.mi.experiencesampling.ExperienceSampling
+import de.luh.hci.mi.experiencesampling.data.Item
+import de.luh.hci.mi.experiencesampling.data.Repository
+import kotlinx.coroutines.launch
+import java.io.IOException
+
+// ViewModel for the statistics screen.
+class StatisticsViewModel constructor(
+    private val repository: Repository, // the underlying repository (data model)
+) : ViewModel() {
+
+    // contexts from data model, const
+    val contexts = repository.getContexts()
+
+    // questionnaire items from data model, const
+    val items = repository.getItems()
+
+    // the currently selected context
+    var selectedContext by mutableStateOf(contexts[0])
+        private set
+
+    fun onContextSelected(context: String) {
+        if (context != selectedContext) {
+            selectedContext = context
+            viewModelScope.launch {
+                try {
+                    ratings = repository.getRatings(context)
+                    for (item in items) {
+                        val rs = ratingState(item)
+                        rs.value = ratings[item] ?: 0f
+                    }
+                } catch (ex: IOException) {
+                    log("exception trying to get ratings (onContextSelected): $ex")
+                }
+            }
+        }
+    }
+
+    private var ratings: Map<Item, Float> = mapOf()
+    private val ratingStates = mutableMapOf<Item, MutableState<Float>>()
+
+    init {
+        viewModelScope.launch {
+            try {
+                ratings = repository.getRatings(selectedContext)
+                for (item in items) {
+                    val rs = ratingState(item)
+                    rs.value = ratings[item] ?: 0f
+                }
+            } catch (ex: IOException) {
+                log("exception trying to get ratings (init): $ex")
+            }
+        }
+    }
+
+    fun ratingState(item: Item): MutableState<Float> {
+        var rating = ratingStates[item]
+        if (rating == null) {
+            rating = mutableFloatStateOf(0f)
+            ratingStates[item] = rating
+        }
+        return rating
+    }
+
+    // Called when this ViewModel is no longer used and will be destroyed. Can be used for cleanup.
+    override fun onCleared() {
+        log("onCleared")
+        ratings = mapOf()
+        ratingStates.clear()
+    }
+
+    // Logs a debug message.
+    private fun log(msg: String) {
+        Log.d(this.javaClass.simpleName, msg)
+    }
+
+    companion object {
+        // Companion object for creating the view model in the right lifecycle scope.
+        val Factory: ViewModelProvider.Factory = viewModelFactory {
+            initializer {
+                val app = this[APPLICATION_KEY] as ExperienceSampling
+                val repository = app.repository
+                StatisticsViewModel(repository)
+            }
+        }
+    }
+
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/theme/Color.kt

@@ -0,0 +1,11 @@
+package de.luh.hci.mi.experiencesampling.ui.theme
+
+import androidx.compose.ui.graphics.Color
+
+val Purple80 = Color(0xFFD0BCFF)
+val PurpleGrey80 = Color(0xFFCCC2DC)
+val Pink80 = Color(0xFFEFB8C8)
+
+val Purple40 = Color(0xFF6650a4)
+val PurpleGrey40 = Color(0xFF625b71)
+val Pink40 = Color(0xFF7D5260)

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/theme/Theme.kt

@@ -0,0 +1,70 @@
+package de.luh.hci.mi.experiencesampling.ui.theme
+
+import android.app.Activity
+import android.os.Build
+import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.darkColorScheme
+import androidx.compose.material3.dynamicDarkColorScheme
+import androidx.compose.material3.dynamicLightColorScheme
+import androidx.compose.material3.lightColorScheme
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.SideEffect
+import androidx.compose.ui.graphics.toArgb
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.LocalView
+import androidx.core.view.WindowCompat
+
+private val DarkColorScheme = darkColorScheme(
+    primary = Purple80,
+    secondary = PurpleGrey80,
+    tertiary = Pink80
+)
+
+private val LightColorScheme = lightColorScheme(
+    primary = Purple40,
+    secondary = PurpleGrey40,
+    tertiary = Pink40
+
+    /* Other default colors to override
+    background = Color(0xFFFFFBFE),
+    surface = Color(0xFFFFFBFE),
+    onPrimary = Color.White,
+    onSecondary = Color.White,
+    onTertiary = Color.White,
+    onBackground = Color(0xFF1C1B1F),
+    onSurface = Color(0xFF1C1B1F),
+    */
+)
+
+@Composable
+fun ExperienceSamplingTheme(
+    darkTheme: Boolean = isSystemInDarkTheme(),
+    // Dynamic color is available on Android 12+
+    dynamicColor: Boolean = true,
+    content: @Composable () -> Unit
+) {
+    val colorScheme = when {
+        dynamicColor && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S -> {
+            val context = LocalContext.current
+            if (darkTheme) dynamicDarkColorScheme(context) else dynamicLightColorScheme(context)
+        }
+
+        darkTheme -> DarkColorScheme
+        else -> LightColorScheme
+    }
+    val view = LocalView.current
+    if (!view.isInEditMode) {
+        SideEffect {
+            val window = (view.context as Activity).window
+            window.statusBarColor = colorScheme.primary.toArgb()
+            WindowCompat.getInsetsController(window, view).isAppearanceLightStatusBars = darkTheme
+        }
+    }
+
+    MaterialTheme(
+        colorScheme = colorScheme,
+        typography = Typography,
+        content = content
+    )
+}

app/src/main/java/de/luh/hci/mi/experiencesampling/ui/theme/Type.kt

@@ -0,0 +1,34 @@
+package de.luh.hci.mi.experiencesampling.ui.theme
+
+import androidx.compose.material3.Typography
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.sp
+
+// Set of Material typography styles to start with
+val Typography = Typography(
+    bodyLarge = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Normal,
+        fontSize = 16.sp,
+        lineHeight = 24.sp,
+        letterSpacing = 0.5.sp
+    )
+    /* Other default text styles to override
+    titleLarge = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Normal,
+        fontSize = 22.sp,
+        lineHeight = 28.sp,
+        letterSpacing = 0.sp
+    ),
+    labelSmall = TextStyle(
+        fontFamily = FontFamily.Default,
+        fontWeight = FontWeight.Medium,
+        fontSize = 11.sp,
+        lineHeight = 16.sp,
+        letterSpacing = 0.5.sp
+    )
+    */
+)

app/src/main/res/drawable-v24/ic_launcher_foreground.xml

@@ -0,0 +1,30 @@
+<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:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
+        <aapt:attr name="android:fillColor">
+            <gradient
+                android:endX="85.84757"
+                android:endY="92.4963"
+                android:startX="42.9492"
+                android:startY="49.59793"
+                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="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
+        android:strokeWidth="1"
+        android:strokeColor="#00000000" />
+</vector>

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="#3DDC84"
+        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>

app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>

app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+</adaptive-icon>

app/src/main/res/values/colors.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="purple_200">#FFBB86FC</color>
+    <color name="purple_500">#FF6200EE</color>
+    <color name="purple_700">#FF3700B3</color>
+    <color name="teal_200">#FF03DAC5</color>
+    <color name="teal_700">#FF018786</color>
+    <color name="black">#FF000000</color>
+    <color name="white">#FFFFFFFF</color>
+</resources>

app/src/main/res/values/strings.xml

@@ -0,0 +1,45 @@
+<resources>
+    <string name="app_name">ExperienceSampling</string>
+    <string name="submit">Submit</string>
+    <string name="context">Context</string>
+    <string name="channel_id">Experience Sampling</string>
+    <string name="channel_name">Experience Sampling</string>
+    <string name="channel_description">This channel sends notifications that request inputting experience samples.</string>
+    <string name="what_experience">What is your current experience?</string>
+    <string name="context_1">Mobile Interaktion</string>
+    <string name="context_2">Programmieren 1</string>
+    <string name="context_3">Mensa</string>
+    <string name="thank_you">Thank you!</string>
+    <string name="context_question">What is your current context?</string>
+    <string name="enter_experience_sample">Enter Experience Sample</string>
+    <string name="show_statistics">Show Statistics</string>
+    <string name="stop_periodic_sampling">Stop Periodic Sampling</string>
+    <string name="start_periodic_sampling">Start Periodic Sampling</string>
+
+    <!-- questions -->
+    <string name="understanding">Understanding</string>
+    <string name="understanding_question">How easy to comprehend is the lecture material presented?</string>
+    <string name="interest">Interest</string>
+    <string name="interest_question">How interesting is today\'s topic for you?</string>
+    <string name="lecturer">Lecturer</string>
+    <string name="lecturer_question">How would you rate the lecturers preseting style?</string>
+    <string name="slides">Slides</string>
+    <string name="slides_question">Rate how the slides complement the presented material.</string>
+    <string name="grade">School Grade</string>
+    <string name="grade_question">Rate today\'s lecture using school grades</string>
+    <string name="overall">Overall</string>
+    <string name="overall_question">Did you enjoy today\'s lecture overall?</string>
+
+    <!-- scales -->
+    <string name="complicated">complicated</string>
+    <string name="easy">easy</string>
+    <string name="not_interesting">not interesting</string>
+    <string name="interesting">interesting</string>
+    <string name="boring">boring</string>
+    <string name="exciting">exciting</string>
+    <string name="obstructive">obstructive</string>
+    <string name="supportive">supportive</string>
+
+
+
+</resources>

app/src/main/res/values/themes.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+
+    <style name="Theme.ExperienceSampling" parent="android:Theme.Material.Light.NoActionBar" />
+</resources>

app/src/main/res/xml/backup_rules.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample backup rules file; uncomment and customize as necessary.
+   See https://developer.android.com/guide/topics/data/autobackup
+   for details.
+   Note: This file is ignored for devices older that API 31
+   See https://developer.android.com/about/versions/12/backup-restore
+-->
+<full-backup-content>
+    <!--
+   <include domain="sharedpref" path="."/>
+   <exclude domain="sharedpref" path="device.xml"/>
+-->
+</full-backup-content>

app/src/main/res/xml/data_extraction_rules.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+   Sample data extraction rules file; uncomment and customize as necessary.
+   See https://developer.android.com/about/versions/12/backup-restore#xml-changes
+   for details.
+-->
+<data-extraction-rules>
+    <cloud-backup>
+        <!-- TODO: Use <include> and <exclude> to control what is backed up.
+        <include .../>
+        <exclude .../>
+        -->
+    </cloud-backup>
+    <!--
+    <device-transfer>
+        <include .../>
+        <exclude .../>
+    </device-transfer>
+    -->
+</data-extraction-rules>

app/src/test/java/de/luh/hci/mi/experiencesampling/ExampleUnitTest.kt

@@ -0,0 +1,16 @@
+package de.luh.hci.mi.experiencesampling
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+/**
+ * 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)
+    }
+}

build.gradle

@@ -0,0 +1,6 @@
+// Top-level build file where you can add configuration options common to all sub-projects/modules.
+plugins {
+    id 'com.android.application' version '8.0.2' apply false
+    id 'com.android.library' version '8.0.2' apply false
+    id 'org.jetbrains.kotlin.android' version '1.7.20' apply false
+}

gradle.properties

@@ -0,0 +1,23 @@
+# Project-wide Gradle settings.
+# IDE (e.g. Android Studio) users:
+# Gradle settings configured through the IDE *will override*
+# any settings specified in this file.
+# For more details on how to configure your build environment visit
+# http://www.gradle.org/docs/current/userguide/build_environment.html
+# Specifies the JVM arguments used for the daemon process.
+# The setting is particularly useful for tweaking memory settings.
+org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
+# When configured, Gradle will run in incubating parallel mode.
+# This option should only be used with decoupled projects. More details, visit
+# http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
+# org.gradle.parallel=true
+# AndroidX package structure to make it clearer which packages are bundled with the
+# Android operating system, and which are packaged with your app's APK
+# https://developer.android.com/topic/libraries/support-library/androidx-rn
+android.useAndroidX=true
+# Kotlin code style for this project: "official" or "obsolete":
+kotlin.code.style=official
+# Enables namespacing of each library's R class so that its R class includes only the
+# resources declared in the library itself and none from the library's dependencies,
+# thereby reducing the size of the R class for that library
+android.nonTransitiveRClass=true

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Wed Jun 14 13:42:06 CEST 2023
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

@@ -0,0 +1,185 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"

gradlew.bat

@@ -0,0 +1,89 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

settings.gradle

@@ -0,0 +1,16 @@
+pluginManagement {
+    repositories {
+        google()
+        mavenCentral()
+        gradlePluginPortal()
+    }
+}
+dependencyResolutionManagement {
+    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
+    repositories {
+        google()
+        mavenCentral()
+    }
+}
+rootProject.name = "ExperienceSampling"
+include ':app'