adding Lab6_NotificatonsLab

labs/Lab6_NotificationsLab/.gitignore

+# built application files
+*.apk
+*.ap_
+
+# files for the dex VM
+*.dex
+
+# Java class files
+*.class
+
+# generated files
+bin/
+gen/
+
+# Local configuration file (sdk path, etc)
+local.properties
+
+# Eclipse project files
+.classpath
+.settings
+
+# Proguard folder generated by Eclipse
+proguard/
+
+# Intellij project files
+*.iml
+*.ipr
+*.iws
+.idea
+.idea/workspace.xml
+.gradle
+build/
+captures/
+
+# Mac files
+.DS_Store
+
+# Windows thumbnail db
+Thumbs.db

labs/Lab6_NotificationsLab/app/build.gradle

+apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+
+android {
+    compileSdkVersion 26
+    buildToolsVersion '29.0.3'
+
+    defaultConfig {
+        applicationId "course.labs.notificationslab"
+        minSdkVersion 21
+        //noinspection OldTargetApi
+        targetSdkVersion 26
+
+        testApplicationId "course.labs.notificationslab.tests"
+        testInstrumentationRunner "android.test.InstrumentationTestRunner"
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
+        }
+    }
+}
+
+dependencies {
+    androidTestImplementation 'com.jayway.android.robotium:robotium-solo:5.6.3'
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    //noinspection GradleCompatible
+    implementation 'com.android.support:support-v4:26.1.0'
+}
+repositories {
+    mavenCentral()
+}

labs/Lab6_NotificationsLab/app/lint.xml

+<?xml version="1.0" encoding="utf-8"?>
+<lint>
+    <issue id="NewApi">
+        <ignore path="src/course/labs/notificationslab/DownloaderTask.java" />
+    </issue>
+</lint>
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/androidTest/java/course/labs/notificationslab/tests/OldFeedNoNotificationTest.kt

+package course.labs.notificationslab.tests
+
+import android.test.ActivityInstrumentationTestCase2
+import android.view.View
+import com.robotium.solo.Solo
+import course.labs.notificationslab.MainActivity
+import course.labs.notificationslab.R
+import course.labs.notificationslab.TestFrontEndActivity
+
+class OldFeedNoNotificationTest : ActivityInstrumentationTestCase2<TestFrontEndActivity>(TestFrontEndActivity::class.java) {
+    private var solo: Solo? = null
+    @Throws(Exception::class)
+    public override fun setUp() {
+        solo = Solo(instrumentation, activity)
+    }
+
+    @Throws(Exception::class)
+    public override fun tearDown() {
+        solo!!.finishOpenedActivities()
+    }
+
+    fun testRun() {
+        val shortDelay = 2000
+        val longDelay = 10000
+
+        // Wait for activity:
+        // 'course.labs.notificationslab.TestFrontEndActivity'
+        solo!!.waitForActivity(
+                TestFrontEndActivity::class.java, shortDelay)
+
+        // Click on Make Tweets Old
+        solo!!.clickOnView(solo!!
+                .getView(R.id.age_tweets_button))
+
+        // Click on Start Main Activty
+        solo!!.clickOnView(solo!!
+                .getView(R.id.start_main_button))
+
+        // Wait for activity: 'course.labs.notificationslab.MainActivity'
+        assertTrue("course.labs.notificationslab.MainActivity is not found!",
+                solo!!.waitForActivity(
+                        MainActivity::class.java, shortDelay))
+
+        // Assert that: Toast message is shown
+        val msg = activity.getString(R.string.download_in_progress_string)
+        assertTrue("'$msg	' is not shown!",
+                solo!!.searchText(msg))
+        solo!!.waitForView(android.R.id.list)
+        val listView = solo!!.getView(android.R.id.list)
+        solo!!.waitForCondition({ listView.isEnabled }, longDelay)
+        val failMsg = activity.getString(R.string.download_failed_string)
+        val successMsg = activity.getString(R.string.download_succes_string)
+        assertTrue("Toast message did not appear", solo!!.searchText("($failMsg|$successMsg)"))
+
+        // Click on ladygaga
+        solo!!.clickOnView(solo!!.getView(android.R.id.text1))
+
+        // Assert that: 'feed_view' is shown
+        assertTrue("feed_view' is not shown!", solo!!.waitForView<View?>(solo!!
+                .getView(R.id.feed_view)))
+    }
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/androidTest/java/course/labs/notificationslab/tests/OldFeedWithNotificationTest.kt

+package course.labs.notificationslab.tests
+
+import android.test.ActivityInstrumentationTestCase2
+import com.robotium.solo.Solo
+import course.labs.notificationslab.MainActivity
+import course.labs.notificationslab.R
+import course.labs.notificationslab.TestFrontEndActivity
+
+class OldFeedWithNotificationTest : ActivityInstrumentationTestCase2<TestFrontEndActivity>(TestFrontEndActivity::class.java) {
+    private var solo: Solo? = null
+    @Throws(Exception::class)
+    public override fun setUp() {
+        solo = Solo(instrumentation)
+        activity
+    }
+
+    @Throws(Exception::class)
+    public override fun tearDown() {
+        solo!!.finishOpenedActivities()
+    }
+
+    fun testRun() {
+        val shortDelay = 2000
+
+        // Clear the log
+        solo!!.clearLog()
+
+        // Wait for activity:
+        // 'course.labs.notificationslab.TestFrontEndActivity'
+        solo!!.waitForActivity(
+                TestFrontEndActivity::class.java,
+                shortDelay)
+
+        // Click on Make Tweets Old
+        solo!!.clickOnView(solo!!
+                .getView(R.id.age_tweets_button))
+
+        // Click on Start Main Activity
+        solo!!.clickOnView(solo!!
+                .getView(R.id.start_main_button))
+
+        // Wait for activity: 'course.labs.notificationslab.MainActivity'
+        assertTrue(
+                "course.labs.notificationslab.MainActivity is not found!",
+                solo!!.waitForActivity(MainActivity::class.java))
+
+        // Press menu back key
+        solo!!.goBackToActivity("TestFrontEndActivity")
+
+
+/*
+		// Wait for activity:
+		// 'course.labs.notificationslab.TestFrontEndActivity'
+//		assertTrue(
+//				"course.labs.notificationslab.TestFrontEndActivity is not found!",
+//				solo.waitForActivity(course.labs.notificationslab.TestFrontEndActivity.class));
+*/
+        // Wait for activity: 'course.labs.notificationslab.TestFrontEndActivity'
+        assertTrue(
+                "course.labs.notificationslab.TestFrontEndActivity is not found!",
+                solo!!.waitForActivity(TestFrontEndActivity::class.java))
+
+
+        // Robotium can't check notification area directly
+        val msg = activity.getString(R.string.notification_sent_string)
+        assertTrue("Notification was not sent", solo!!.waitForText(msg))
+    }
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/AndroidManifest.xml

+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="course.labs.notificationslab"
+    android:versionCode="1"
+    android:versionName="1.0" >
+
+    <application
+        android:allowBackup="true"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:theme="@style/AppTheme"
+        android:fullBackupContent="@xml/backup_descriptor">
+        <activity
+            android:name="course.labs.notificationslab.MainActivity"
+            android:label="@string/app_name" >
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+        <activity
+            android:name="course.labs.notificationslab.TestFrontEndActivity"
+            android:label="@string/title_activity_test_front_end" >
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/java/course/labs/notificationslab/DownloadFinishedListener.kt

+package course.labs.notificationslab
+
+internal interface DownloadFinishedListener {
+    open fun notifyDataRefreshed(feeds: Array<String?>?)
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/java/course/labs/notificationslab/DownloaderTaskFragment.kt

+@file:Suppress("unused")
+
+package course.labs.notificationslab
+
+import android.annotation.SuppressLint
+import android.app.*
+import android.content.BroadcastReceiver
+import android.content.Context
+import android.content.Intent
+import android.os.AsyncTask
+import android.os.Build
+import android.os.Bundle
+import android.support.v4.app.Fragment
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.RemoteViews
+import android.widget.Toast
+import java.io.*
+
+class DownloaderTaskFragment : Fragment() {
+    private var mDownloaderTask: DownloaderTask? = null
+    private var mCallback: DownloadFinishedListener? = null
+    private lateinit var mContext: Context
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
+                              savedInstanceState: Bundle?): View? {
+        super.onCreate(savedInstanceState)
+
+        mDownloaderTask = DownloaderTask()
+
+        val tmp = arguments.getIntegerArrayList(
+                MainActivity.TAG_FRIEND_RES_IDS)
+        var feeds = arrayOfNulls<Int>(tmp!!.size)
+        feeds = tmp.toArray(feeds)
+
+        mDownloaderTask!!.execute(*feeds)
+
+        return inflater.inflate(R.layout.feed, container, false)
+    }
+
+    // Assign current hosting Activity to mCallback
+    // Store application context for use by downloadTweets()
+    override fun onAttach(context: Context) {
+        super.onAttach(context)
+        mContext = context
+
+        // Make sure that the hosting activity has implemented
+        // the correct callback interface.
+
+        try {
+
+            mCallback = context as DownloadFinishedListener
+
+        } catch (e: ClassCastException) {
+            throw ClassCastException("$context must implement DownloadFinishedListener")
+        }
+    }
+
+    // Null out mCallback
+    override fun onDetach() {
+        super.onDetach()
+        mCallback = null
+    }
+
+
+    // This class is an AsyncTask, Async has been deprecated by API 30, therefore
+    // you will not have to implement doInBackground and onPostExecute
+    @SuppressLint("StaticFieldLeak")
+    inner class DownloaderTask : AsyncTask<Int?, Void?, Array<String?>>() {
+        override fun doInBackground(vararg resourceIDs: Int?): Array<String?> {
+            return downloadTweets(resourceIDs as Array<Int>)
+        }
+
+        // Simulates downloading Twitter data from the network
+        private fun downloadTweets(resourceIDS: Array<Int>): Array<String?> {
+            val simulatedDelay = 2000
+            val feeds = arrayOfNulls<String>(resourceIDS.size)
+            var downLoadCompleted = false
+            try {
+                for (idx in resourceIDS.indices) {
+                    var `in`: BufferedReader
+                    try {
+                        // Pretend downloading takes a long time
+                        Thread.sleep(simulatedDelay.toLong())
+                    } catch (e: InterruptedException) {
+                        e.printStackTrace()
+                    }
+                    val inputStream: InputStream? = mContext.resources.openRawResource(
+                            resourceIDS[idx])
+                    `in` = BufferedReader(InputStreamReader(inputStream))
+                    var readLine: String?
+                    val buf = StringBuffer()
+                    while (`in`.readLine().also { readLine = it } != null) {
+                        buf.append(readLine)
+                    }
+                    feeds[idx] = buf.toString()
+                    `in`.close()
+                }
+                downLoadCompleted = true
+                saveTweetsToFile(feeds)
+            } catch (e: IOException) {
+                e.printStackTrace()
+            }
+
+            // Notify user that downloading has finished
+            notify(downLoadCompleted)
+            return feeds
+        }
+
+        // If necessary, notifies the user that the tweet downloads are
+        // complete. Sends an ordered broadcast back to the BroadcastReceiver in
+        // MainActivity to determine whether the notification is necessary.
+        private fun notify(success: Boolean) {
+            val restartMainActivityIntent = Intent(mContext,
+                    MainActivity::class.java)
+            restartMainActivityIntent.flags = Intent.FLAG_ACTIVITY_NEW_TASK
+
+            // Sends an ordered broadcast to determine whether MainActivity is
+            // active and in the foreground. Creates a new BroadcastReceiver
+            // to receive a result indicating the state of MainActivity
+
+            // TODO: The Action for this broadcast Intent is MainActivity.DATA_REFRESHED_ACTION
+            // The result, MainActivity.IS_ALIVE, indicates that MainActivity is
+            // active and in the foreground.
+            mContext.sendOrderedBroadcast(Intent(
+                    MainActivity.DATA_REFRESHED_ACTION), null,
+                    object : BroadcastReceiver() {
+                        val failMsg = mContext
+                                .getString(R.string.download_failed_string)
+                        val successMsg = mContext
+                                .getString(R.string.download_succes_string)
+                        val notificationSentMsg = mContext
+                                .getString(R.string.notification_sent_string)
+
+                        override fun onReceive(context: Context, intent: Intent) {
+
+                            // TODO: Check whether or not the MainActivity
+                            // received the broadcast
+                            if (true) {
+
+                                // TODO: If not, create a PendingIntent using the
+                                // restartMainActivityIntent and set its flags
+                                // to FLAG_UPDATE_CURRENT
+
+                                // Uses R.layout.custom_notification for the
+                                // layout of the notification View. The xml
+                                // file is in res/layout/custom_notification.xml
+                                val mContentView = RemoteViews(
+                                        mContext.packageName,
+                                        R.layout.custom_notification)
+
+                                // TODO: Set the notification View's text to
+                                // reflect whether the download completed
+                                // successfully
+
+                                // TODO: Use the Notification.Builder class to
+                                // create the Notification. You will have to set
+                                // several pieces of information. You can use
+                                // android.R.drawable.stat_sys_warning
+                                // for the small icon. You should also
+                                // setAutoCancel(true).
+
+                                // TODO: Send the notification
+                            } else {
+                                Toast.makeText(mContext,
+                                        if (success) successMsg else failMsg,
+                                        Toast.LENGTH_LONG).show()
+                            }
+                        }
+                    }, null, 0, null, null)
+        }
+
+        private val channelID = "my_channel_01"
+        private fun createNotificationChannel() {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+                // TODO: Create Notification Channel with id channelID,
+                // name R.string.channel_name
+                // and description R.string.channel_description of high importance
+            }
+        }
+
+        // Saves the tweets to a file
+        private fun saveTweetsToFile(result: Array<String?>) {
+            var writer: PrintWriter? = null
+            try {
+                val fos = mContext.openFileOutput(
+                        MainActivity.TWEET_FILENAME, Context.MODE_PRIVATE)
+                writer = PrintWriter(BufferedWriter(
+                        OutputStreamWriter(fos)))
+                for (s in result) {
+                    writer.println(s)
+                }
+            } catch (e: IOException) {
+                e.printStackTrace()
+            } finally {
+                writer?.close()
+            }
+        }
+
+        // Pass newly available data back to hosting Activity
+        // using the DownloadFinishedListener interface
+        override fun onPostExecute(result: Array<String?>) {
+            super.onPostExecute(result)
+            if (null != mCallback) {
+                mCallback!!.notifyDataRefreshed(result)
+            }
+        }
+    }
+
+    companion object {
+        private const val TAG = "Lab-Notifications"
+        private const val MY_NOTIFICATION_ID = 11151990
+    }
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/java/course/labs/notificationslab/FeedFragment.kt

+package course.labs.notificationslab
+
+import android.os.Bundle
+import android.support.v4.app.Fragment
+import android.util.Log
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import android.widget.TextView
+
+class FeedFragment : Fragment() {
+
+    private var mTextView: TextView? = null
+    private var feedFragmentData: FeedFragmentData? = null
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
+                              savedInstanceState: Bundle?): View? {
+        return inflater.inflate(R.layout.feed, container, false)
+
+    }
+
+    override fun onActivityCreated(savedInstanceState: Bundle?) {
+        super.onActivityCreated(savedInstanceState)
+
+        // Read in all Twitter feeds
+        if (null == feedFragmentData) {
+            feedFragmentData = FeedFragmentData(activity)
+        }
+    }
+
+    // Display Twitter feed for selected feed
+    fun updateFeedDisplay(position: Int) {
+
+        Log.i(TAG, "Entered updateFeedDisplay()")
+
+        mTextView = view!!.findViewById<View>(R.id.feed_view) as TextView
+        mTextView!!.text = feedFragmentData!!.getFeed(position)
+
+    }
+
+    companion object {
+        private const val TAG = "Lab-Notifications"
+    }
+
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/java/course/labs/notificationslab/FeedFragmentData.kt

+package course.labs.notificationslab
+
+import android.content.Context
+import android.util.Log
+import android.util.SparseArray
+import org.json.JSONArray
+import org.json.JSONException
+import org.json.JSONObject
+import java.io.BufferedReader
+import java.io.IOException
+import java.io.InputStreamReader
+
+// Utility class that provides stored Twitter feed data
+
+class FeedFragmentData(private val mContext: Context) {
+
+    private val mFeeds = SparseArray<String>()
+
+
+    init {
+        loadFeeds()
+    }
+
+    // Load all stored Twitter feeds into the mFeeds SparseArray.
+
+    private fun loadFeeds() {
+
+        for (id in IDS) {
+
+            val inputStream = mContext.resources.openRawResource(
+                    id)
+            val reader =  BufferedReader(InputStreamReader(
+                    inputStream))
+
+            val buffer = StringBuffer("")
+
+
+            // Read raw data from resource file
+
+            try {
+
+                var line = reader.readLine()
+                while (line != null) {
+                    buffer.append(line)
+                    line = reader.readLine()
+                }
+
+            } catch (e: IOException) {
+                Log.i(TAG, "IOException")
+            }
+
+            // Convert raw data into a String
+
+            var feed: JSONArray? = null
+            try {
+                feed = JSONArray(buffer.toString())
+            } catch (e: JSONException) {
+                Log.i(TAG, "JSONException")
+            }
+
+            mFeeds.put(id, procFeed(feed!!))
+
+        }
+    }
+
+
+    // Convert JSON formatted data to a String
+
+    private fun procFeed(feed: JSONArray): String {
+
+        var name = ""
+        var tweet = ""
+
+        // string buffer for twitter feeds
+        val textFeed = StringBuffer("")
+
+        for (j in 0 until feed.length()) {
+            try {
+
+                tweet = feed.getJSONObject(j).getString("text")
+                val user = feed.getJSONObject(j)
+                        .get("user") as JSONObject
+                name = user.getString("name")
+
+            } catch (e: JSONException) {
+
+                Log.i(TAG, "JSONException while processing feed")
+            }
+
+            textFeed.append("$name - $tweet\n\n")
+        }
+
+        return textFeed.toString()
+    }
+
+    // Return the Twitter feed data for the specified position as a single String
+
+    internal fun getFeed(position: Int): String {
+
+        return mFeeds.get(IDS[position])
+
+    }
+
+    companion object {
+        private const val TAG = "FeedFragmentData"
+        private val IDS = intArrayOf(R.raw.ladygaga, R.raw.rebeccablack, R.raw.taylorswift)
+    }
+}

labs/Lab6_NotificationsLab/app/src/main/java/course/labs/notificationslab/FriendsFragment.kt

+package course.labs.notificationslab
+
+import android.content.Context
+import android.os.Bundle
+import android.support.v4.app.ListFragment
+import android.util.Log
+import android.view.View
+import android.widget.ArrayAdapter
+import android.widget.ListView
+
+class FriendsFragment : ListFragment() {
+
+    private lateinit var mCallback: SelectionListener
+
+    interface SelectionListener {
+        fun onItemSelected(position: Int)
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        // Set the list adapter for this ListFragment
+        listAdapter = ArrayAdapter(activity, android.R.layout.simple_list_item_activated_1, FRIENDS)
+    }
+
+
+    override fun onAttach(context: Context) {
+        super.onAttach(context)
+
+        // Make sure that the hosting Activity has implemented
+        // the SelectionListener callback interface. We need this
+        // because when an item in this ListFragment is selected,
+        // the hosting Activity's onItemSelected() method will be called.
+
+        try {
+            mCallback = context as SelectionListener
+        } catch (e: ClassCastException) {
+            throw ClassCastException("$context must implement SelectionListener")
+        }
+    }
+
+    override fun onActivityCreated(savedInstanceState: Bundle?) {
+        super.onActivityCreated(savedInstanceState)
+        Log.i(TAG, "Entered onActivityCreated()")
+    }
+
+    override fun onListItemClick(l: ListView, view: View, position: Int, id: Long) {
+
+        // Notify the hosting Activity that a selection has been made.
+
+        mCallback.onItemSelected(position)
+    }
+
+    companion object {
+
+        private val FRIENDS = arrayOf("ladygaga", "msrebeccablack", "taylorswift13")
+        private const val TAG = "Lab-Notifications"
+    }
+
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/java/course/labs/notificationslab/MainActivity.kt

+package course.labs.notificationslab
+
+import android.content.BroadcastReceiver
+import android.content.Intent
+import android.content.Context
+import android.content.IntentFilter
+import android.support.v4.app.FragmentActivity
+import android.os.Bundle
+import android.util.Log
+import android.widget.Toast
+import org.json.JSONArray
+import org.json.JSONException
+import org.json.JSONObject
+import java.io.BufferedReader
+import java.io.FileNotFoundException
+import java.io.IOException
+import java.io.InputStreamReader
+
+class MainActivity : FragmentActivity(), FriendsFragment.SelectionListener, DownloadFinishedListener {
+
+    private lateinit var mFriendsFragment: FriendsFragment
+    private lateinit var mFeedFragment: FeedFragment
+    private lateinit var mDownloaderFragment: DownloaderTaskFragment
+
+    private var mIsInteractionEnabled = false
+    private var mFormattedFeeds: Array<String?>? = arrayOfNulls<String?>(sRawTextFeedIds.size)
+    private var mIsFresh = false
+    private var mRefreshReceiver: BroadcastReceiver? = null
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        Log.d(TAG, "Starting MainActivity")
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_main)
+
+        mFeedFragment = FeedFragment()
+
+        // Reset instance state on reconfiguration
+        if (null != savedInstanceState) {
+            restoreState(savedInstanceState)
+        } else {
+            setupFragments()
+        }
+    }
+
+    // One time setup of UI and retained (headless) Fragment
+    private fun setupFragments() {
+        installFriendsFragment()
+
+        // The feed is fresh if it was downloaded less than 2 minutes ago
+        mIsFresh = System.currentTimeMillis() - getFileStreamPath(
+                TWEET_FILENAME).lastModified() < TWO_MIN
+        if (!mIsFresh) {
+            installDownloaderTaskFragment()
+
+            // TODO: Show a Toast message displaying
+            // R.string.download_in_progress string
+
+            // Set up a BroadcastReceiver to receive an Intent when download
+            // finishes.
+            mRefreshReceiver = object : BroadcastReceiver() {
+                override fun onReceive(context: Context?, intent: Intent?) {
+                    // TODO: Check to make sure this is an ordered broadcast
+                    // Let sender know that the Intent was received
+                    // by setting result code to MainActivity.IS_ALIVE
+                }
+            }
+        } else {
+            // Process Twitter data taken from stored file
+            parseJSON(loadTweetsFromFile())
+
+            // Enable user interaction
+            mIsInteractionEnabled = true
+        }
+    }
+
+    // Add Friends Fragment to Activity
+    private fun installFriendsFragment() {
+
+        // Make new Fragment
+        mFriendsFragment = FriendsFragment()
+
+        // Give Fragment to the FragmentManager
+        val transaction = supportFragmentManager.beginTransaction()
+        transaction.replace(R.id.fragment_container, mFriendsFragment,
+                TAG_FRIENDS_FRAGMENT)
+        transaction.commit()
+    }
+
+    // Add DownloaderTaskFragment to Activity
+    private fun installDownloaderTaskFragment() {
+
+        // Make new Fragment
+        mDownloaderFragment = DownloaderTaskFragment()
+
+        // Set DownloaderTaskFragment arguments
+        val args = Bundle()
+        args.putIntegerArrayList(TAG_FRIEND_RES_IDS, sRawTextFeedIds)
+        mDownloaderFragment.arguments = args
+
+        // Give Fragment to the FragmentManager
+        supportFragmentManager.beginTransaction()
+                .add(mDownloaderFragment, TAG_DOWNLOADER_FRAGMENT).commit()
+    }
+
+    // Register the BroadcastReceiver
+    override fun onResume() {
+        super.onResume()
+
+        // TODO: Register the BroadcastReceiver to receive a
+        // DATA_REFRESHED_ACTION broadcast
+    }
+
+    override fun onPause() {
+
+        // TODO: Unregister the BroadcastReceiver if it has been registered
+        // Note: check that mRefreshReceiver is not null before attempting to
+        // unregister in order to work around an Instrumentation issue
+
+        super.onPause()
+    }
+
+    /*
+	 * DownloadFinishedListener method
+	 */
+    // Called back by DownloaderTask after data has been loaded
+    override fun notifyDataRefreshed(feeds: Array<String?>?) {
+
+        // Process downloaded data
+        parseJSON(feeds)
+
+        // Enable user interaction
+        mIsInteractionEnabled = true
+    }
+
+    // Installs the FeedFragment when a Friend name is
+    // selected in the FriendsFragment
+    override fun onItemSelected(position: Int) {
+        if (mFeedFragment == null) {
+            mFeedFragment = FeedFragment()
+    }
+
+        val transaction = supportFragmentManager.beginTransaction()
+
+        transaction.replace(R.id.fragment_container, mFeedFragment)
+        transaction.addToBackStack(null)
+        transaction.commit()
+
+        supportFragmentManager.executePendingTransactions()
+
+        mFeedFragment.updateFeedDisplay(position)
+    }
+
+    // Restore saved instance state
+    private fun restoreState(savedInstanceState: Bundle?) {
+
+        // Fragments tags were saved in onSavedInstanceState
+        mFriendsFragment = supportFragmentManager
+                .findFragmentByTag(savedInstanceState!!
+                        .getString(TAG_FRIENDS_FRAGMENT)) as FriendsFragment
+        mFeedFragment = supportFragmentManager
+                .findFragmentByTag(savedInstanceState
+                        .getString(TAG_FEED_FRAGMENT)) as FeedFragment
+        mDownloaderFragment = supportFragmentManager
+                .findFragmentByTag(savedInstanceState
+                        .getString(TAG_DOWNLOADER_FRAGMENT)) as DownloaderTaskFragment
+        mIsInteractionEnabled = savedInstanceState
+                .getBoolean(TAG_IS_DATA_AVAILABLE)
+        if (mIsInteractionEnabled) {
+            mFormattedFeeds = savedInstanceState
+                    .getStringArray(TAG_PROCESSED_FEEDS)
+        }
+    }
+
+    // Convert raw data (in JSON format) into text for display
+    private fun parseJSON(feeds: Array<String?>?) {
+        val jsonFeeds = arrayOfNulls<JSONArray?>(feeds!!.size)
+        for (i in jsonFeeds.indices) {
+            try {
+                jsonFeeds[i] = JSONArray(feeds[i])
+            } catch (e: JSONException) {
+                e.printStackTrace()
+            }
+            var name = ""
+            var tweet = ""
+            val tmp = jsonFeeds[i]
+
+            // string buffer for feeds
+            val tweetRec = StringBuffer("")
+            for (j in 0 until tmp!!.length()) {
+                try {
+                    tweet = tmp.getJSONObject(j).getString(TAG_TEXT)
+                    val user = tmp.getJSONObject(j)[TAG_USER] as JSONObject
+                    name = user.getString(TAG_NAME)
+                } catch (e: JSONException) {
+                    e.printStackTrace()
+                }
+                tweetRec.append("$name - $tweet\n\n")
+            }
+        }
+    }
+
+    // Retrieve feeds text from a file
+    // Store them in mRawTextFeed[]
+    private fun loadTweetsFromFile(): Array<String?>? {
+        var reader: BufferedReader? = null
+        val rawFeeds = ArrayList<String?>()
+        try {
+            val fis = openFileInput(TWEET_FILENAME)
+            reader = BufferedReader(InputStreamReader(fis))
+            var s: String?
+            var i = 0
+            while (null != reader.readLine().also { s = it }) {
+                rawFeeds.add(i, s)
+                i++
+            }
+        } catch (e: FileNotFoundException) {
+            e.printStackTrace()
+        } catch (e: IOException) {
+            e.printStackTrace()
+        } finally {
+            if (null != reader) {
+                try {
+                    reader.close()
+                } catch (e: IOException) {
+                    e.printStackTrace()
+                }
+            }
+        }
+        return rawFeeds.toTypedArray()
+    }
+
+    companion object {
+        private const val TAG_NAME: String = "name"
+        private const val TAG_USER: String = "user"
+        private const val TAG_TEXT: String = "text"
+        private const val TAG_FRIENDS_FRAGMENT: String = "friends_fragment"
+        private const val TAG_FEED_FRAGMENT: String = "feed_fragment"
+        private const val TAG_DOWNLOADER_FRAGMENT: String = "downloader_fragment"
+        private const val TAG_IS_DATA_AVAILABLE: String = "is_data_available"
+        private const val TAG_PROCESSED_FEEDS: String = "processed_feeds"
+
+        const val TAG_FRIEND_RES_IDS: String = "friends"
+        const val TWEET_FILENAME: String = "tweets.txt"
+        const val IS_ALIVE = RESULT_FIRST_USER
+        const val DATA_REFRESHED_ACTION: String = "course.labs.notificationslabnew.DATA_REFRESHED"
+
+        private const val TAG: String = "Lab-Notifications"
+
+        // Raw feed file IDs used to reference stored tweet data
+        val sRawTextFeedIds: ArrayList<Int> = arrayListOf(R.raw.ladygaga, R.raw.rebeccablack, R.raw.taylorswift)
+        private const val TWO_MIN = 2 * 60 * 1000.toLong()
+    }
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/java/course/labs/notificationslab/TestFrontEndActivity.kt

+package course.labs.notificationslab
+
+import android.app.Activity
+import android.content.Intent
+import android.content.res.Resources.NotFoundException
+import android.os.Bundle
+import android.util.Log
+import android.view.View
+import android.widget.Button
+import java.io.*
+
+class TestFrontEndActivity : Activity() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        Log.d(TAG, "Starting FrontEndActivity...")
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_test_front_end)
+        sFileName = filesDir.toString() + "/" + MainActivity.TWEET_FILENAME
+        val ageTweetsButton = findViewById<View?>(R.id.age_tweets_button) as Button
+        ageTweetsButton.setOnClickListener { setFileAge(DAWN_OF_TIME) }
+        val rejuvTweetsButton = findViewById<View?>(R.id.rejuv_tweets_button) as Button
+        rejuvTweetsButton.setOnClickListener { setFileAge(System.currentTimeMillis()) }
+        val startMainActivityButton = findViewById<View?>(R.id.start_main_button) as Button
+        startMainActivityButton.setOnClickListener {
+            startActivity(Intent(this@TestFrontEndActivity,
+                    MainActivity::class.java))
+        }
+        createTweetFileIfMissing()
+    }
+
+    private fun createTweetFileIfMissing() {
+        val file = File(sFileName)
+        if (!file.exists()) {
+            var out: PrintWriter? = null
+            var `in`: BufferedReader? = null
+            try {
+                out = PrintWriter(BufferedWriter(
+                        OutputStreamWriter(openFileOutput(
+                                MainActivity.TWEET_FILENAME,
+                                MODE_PRIVATE))))
+                for (resId in MainActivity.sRawTextFeedIds) {
+                    `in` = BufferedReader(InputStreamReader(
+                            resources.openRawResource(resId)))
+                    var line: String?
+                    val buffer = StringBuffer()
+                    while (`in`.readLine().also { line = it } != null) {
+                        buffer.append(line)
+                    }
+                    out.println(buffer)
+                }
+            } catch (e: FileNotFoundException) {
+                e.printStackTrace()
+            } catch (e: NotFoundException) {
+                e.printStackTrace()
+            } catch (e: IOException) {
+                e.printStackTrace()
+            } finally {
+                try {
+                    `in`?.close()
+                    out?.close()
+                } catch (e: IOException) {
+                    e.printStackTrace()
+                }
+            }
+        }
+    }
+
+    private fun setFileAge(timestamp: Long) {
+        val file = File(sFileName)
+        if (file.exists()) {
+            file.setLastModified(timestamp)
+        }
+    }
+
+    companion object {
+        private const val DAWN_OF_TIME: Long = 0
+        private val TAG: String? = "TestFrontEndActivity"
+        private var sFileName: String? = null
+    }
+}
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/res/layout/activity_main.xml

+<?xml version="1.0" encoding="utf-8"?>
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/fragment_container"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:ignore="MergeRootFrame" />
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/res/layout/activity_test_front_end.xml

+<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"
+    android:orientation="vertical"
+    android:paddingBottom="@dimen/activity_vertical_margin"
+    android:paddingLeft="@dimen/activity_horizontal_margin"
+    android:paddingRight="@dimen/activity_horizontal_margin"
+    android:paddingTop="@dimen/activity_vertical_margin"
+    tools:context=".TestFrontEndActivity" >
+
+    <Button
+        android:id="@+id/rejuv_tweets_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_horizontal"
+        android:layout_margin="@dimen/base_margin"
+        android:text="@string/make_tweets_new" />
+
+    <Button
+        android:id="@+id/age_tweets_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_horizontal"
+        android:layout_margin="@dimen/base_margin"
+        android:text="@string/make_tweets_old" />
+
+    <Button
+        android:id="@+id/start_main_button"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_horizontal"
+        android:layout_margin="@dimen/base_margin"
+        android:text="@string/start_main_activity" />
+
+</LinearLayout>
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/res/layout/custom_notification.xml

+<?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:id="@+id/toast_layout_root"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:background="#7777"
+    android:padding="3dp"
+    tools:ignore="Overdraw">
+    
+    <ImageView
+        android:id="@+id/image"
+        android:layout_width="44dp"
+        android:layout_height="44dp"
+        android:layout_marginEnd="10dp"
+        android:contentDescription="@string/alert_string"
+        android:src="@android:drawable/ic_dialog_info" />
+    
+    <TextView
+        android:id="@+id/text"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:textColor="#FFF"
+        android:textSize="24sp" />
+    
+</LinearLayout>
\ No newline at end of file

labs/Lab6_NotificationsLab/app/src/main/res/layout/feed.xml

+<ScrollView 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=".FeedFragment" >
+
+    <TextView
+        android:id="@+id/feed_view"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_margin="8dp"/>
+
+</ScrollView>
\ No newline at end of file