From bce5d7b2ea8f7bc7d2db7811af7a07520cdd1ec8 Mon Sep 17 00:00:00 2001
From: Sagar <sagar.0dev@gmail.com>
Date: Mon, 24 Jan 2022 18:06:34 +0530
Subject: [PATCH 1/3] stable exercise 1

---
 app/build.gradle                              | 22 ++++-----
 .../ExampleInstrumentedTest.java              |  4 +-
 .../classicalmusicquiz/MainActivity.java      |  2 +-
 .../classicalmusicquiz/QuizActivity.java      | 47 ++++++++++++-------
 .../android/classicalmusicquiz/Sample.java    |  5 +-
 app/src/main/res/layout/activity_main.xml     |  4 +-
 app/src/main/res/layout/activity_quiz.xml     | 12 ++---
 build.gradle                                  |  8 ++--
 gradle.properties                             |  2 +
 gradle/wrapper/gradle-wrapper.properties      |  2 +-
 10 files changed, 62 insertions(+), 46 deletions(-)

diff --git a/app/build.gradle b/app/build.gradle
index cba54cd5..1155d00a 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,15 +1,15 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 25
-    buildToolsVersion "25.0.2"
+    compileSdkVersion 31
+    buildToolsVersion "30.0.3"
     defaultConfig {
         applicationId "com.example.android.classicalmusicquiz"
-        minSdkVersion 15
-        targetSdkVersion 25
+        minSdkVersion 17
+        targetSdkVersion 31
         versionCode 1
         versionName "1.0"
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
     }
     buildTypes {
         release {
@@ -20,12 +20,12 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libs', include: ['*.jar'])
-    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    androidTestImplementation('androidx.test.espresso:espresso-core:3.1.0', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-    compile 'com.google.android.exoplayer:exoplayer:r2.2.0'
-    compile 'com.android.support:appcompat-v7:25.3.0'
-    testCompile 'junit:junit:4.12'
-    compile 'com.android.support.constraint:constraint-layout:1.0.2'
+    implementation 'com.google.android.exoplayer:exoplayer:2.16.1'
+    implementation 'androidx.appcompat:appcompat:1.4.1'
+    testImplementation 'junit:junit:4.13.2'
+    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
 }
diff --git a/app/src/androidTest/java/com/example/android/classicalmusicquiz/ExampleInstrumentedTest.java b/app/src/androidTest/java/com/example/android/classicalmusicquiz/ExampleInstrumentedTest.java
index 1b90a51c..25a97ed4 100644
--- a/app/src/androidTest/java/com/example/android/classicalmusicquiz/ExampleInstrumentedTest.java
+++ b/app/src/androidTest/java/com/example/android/classicalmusicquiz/ExampleInstrumentedTest.java
@@ -1,8 +1,8 @@
 package com.example.android.classicalmusicquiz;
 
 import android.content.Context;
-import android.support.test.InstrumentationRegistry;
-import android.support.test.runner.AndroidJUnit4;
+import androidx.test.platform.app.InstrumentationRegistry;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/app/src/main/java/com/example/android/classicalmusicquiz/MainActivity.java b/app/src/main/java/com/example/android/classicalmusicquiz/MainActivity.java
index 48060b63..bcbbf6b0 100644
--- a/app/src/main/java/com/example/android/classicalmusicquiz/MainActivity.java
+++ b/app/src/main/java/com/example/android/classicalmusicquiz/MainActivity.java
@@ -18,7 +18,7 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.support.v7.app.AppCompatActivity;
+import androidx.appcompat.app.AppCompatActivity;
 import android.view.View;
 import android.widget.TextView;
 
diff --git a/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java b/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java
index 1de123cd..e74ea442 100644
--- a/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java
+++ b/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java
@@ -17,34 +17,36 @@
 package com.example.android.classicalmusicquiz;
 
 import android.content.Intent;
+import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.graphics.Color;
 import android.graphics.PorterDuff;
+import android.graphics.drawable.BitmapDrawable;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
-import android.support.v4.content.ContextCompat;
-import android.support.v7.app.AppCompatActivity;
+import androidx.core.content.ContextCompat;
+import androidx.appcompat.app.AppCompatActivity;
 import android.view.View;
 import android.widget.Button;
 import android.widget.Toast;
-
 import com.google.android.exoplayer2.DefaultLoadControl;
-import com.google.android.exoplayer2.ExoPlayerFactory;
+import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.LoadControl;
+import com.google.android.exoplayer2.Player;
 import com.google.android.exoplayer2.SimpleExoPlayer;
 import com.google.android.exoplayer2.extractor.DefaultExtractorsFactory;
-import com.google.android.exoplayer2.source.ExtractorMediaSource;
 import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.source.ProgressiveMediaSource;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.trackselection.TrackSelector;
-import com.google.android.exoplayer2.ui.SimpleExoPlayerView;
+import com.google.android.exoplayer2.ui.PlayerView;
 import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
 import com.google.android.exoplayer2.util.Util;
 
 import java.util.ArrayList;
 
-public class QuizActivity extends AppCompatActivity implements View.OnClickListener {
+public class QuizActivity extends AppCompatActivity implements View.OnClickListener, Player.Listener {
 
     private static final int CORRECT_ANSWER_DELAY_MILLIS = 1000;
     private static final String REMAINING_SONGS_KEY = "remaining_songs";
@@ -55,8 +57,8 @@ public class QuizActivity extends AppCompatActivity implements View.OnClickListe
     private int mCurrentScore;
     private int mHighScore;
     private Button[] mButtons;
-    private SimpleExoPlayer mExoPlayer;
-    private SimpleExoPlayerView mPlayerView;
+    private ExoPlayer mExoPlayer;
+    private PlayerView mPlayerView;
 
 
     @Override
@@ -66,7 +68,7 @@ protected void onCreate(Bundle savedInstanceState) {
 
 
         // Initialize the player view.
-        mPlayerView = (SimpleExoPlayerView) findViewById(R.id.playerView);
+        mPlayerView = (PlayerView) findViewById(R.id.playerView);
 
         boolean isNewGame = !getIntent().hasExtra(REMAINING_SONGS_KEY);
 
@@ -88,8 +90,7 @@ protected void onCreate(Bundle savedInstanceState) {
         mAnswerSampleID = QuizUtils.getCorrectAnswerID(mQuestionSampleIDs);
 
         // Load the question mark as the background image until the user answers the question.
-        mPlayerView.setDefaultArtwork(BitmapFactory.decodeResource
-                (getResources(), R.drawable.question_mark));
+        mPlayerView.setDefaultArtwork(new BitmapDrawable(BitmapFactory.decodeResource(getResources(), R.drawable.question_mark)));
 
         // If there is only one answer left, end the game.
         if (mQuestionSampleIDs.size() < 2) {
@@ -99,7 +100,7 @@ protected void onCreate(Bundle savedInstanceState) {
 
         // Initialize the buttons with the composers names.
         mButtons = initializeButtons(mQuestionSampleIDs);
-        
+
         Sample answerSample = Sample.getSampleByID(this, mAnswerSampleID);
         if (answerSample == null) {
             Toast.makeText(this, getString(R.string.sample_not_found_error),
@@ -143,12 +144,23 @@ private void initializePlayer(Uri mediaUri) {
             // Create an instance of the ExoPlayer.
             TrackSelector trackSelector = new DefaultTrackSelector();
             LoadControl loadControl = new DefaultLoadControl();
-            mExoPlayer = ExoPlayerFactory.newSimpleInstance(this, trackSelector, loadControl);
+
+            mExoPlayer = new ExoPlayer.Builder(this)
+                    .setTrackSelector(trackSelector)
+                    .setLoadControl(loadControl).build();
             mPlayerView.setPlayer(mExoPlayer);
+
+            // Set the ExoPlayer.EventListener to this activity.
+            mExoPlayer.addListener(this);
+
             // Prepare the MediaSource.
             String userAgent = Util.getUserAgent(this, "ClassicalMusicQuiz");
-            MediaSource mediaSource = new ExtractorMediaSource(mediaUri, new DefaultDataSourceFactory(
-                    this, userAgent), new DefaultExtractorsFactory(), null, null);
+
+            DefaultDataSourceFactory defaultDataSourceFactory = new DefaultDataSourceFactory(this, userAgent);
+            DefaultExtractorsFactory defaultExtractorsFactory = new DefaultExtractorsFactory();
+            MediaSource mediaSource = new ProgressiveMediaSource.Factory(defaultDataSourceFactory,
+                    defaultExtractorsFactory).createMediaSource(mediaUri);
+
             mExoPlayer.prepare(mediaSource);
             mExoPlayer.setPlayWhenReady(true);
         }
@@ -224,7 +236,8 @@ public void run() {
      * show the correct answer.
      */
     private void showCorrectAnswer() {
-        mPlayerView.setDefaultArtwork(Sample.getComposerArtBySampleID(this, mAnswerSampleID));
+        Bitmap bitmap=Sample.getComposerArtBySampleID(this, mAnswerSampleID);
+        mPlayerView.setDefaultArtwork(new BitmapDrawable(bitmap));
         for (int i = 0; i < mQuestionSampleIDs.size(); i++) {
             int buttonSampleID = mQuestionSampleIDs.get(i);
 
diff --git a/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java b/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java
index 610a89f4..35d73446 100644
--- a/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java
+++ b/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java
@@ -30,6 +30,7 @@
 import com.google.android.exoplayer2.upstream.DefaultDataSource;
 import com.google.android.exoplayer2.util.Util;
 
+import java.io.Closeable;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
@@ -182,7 +183,7 @@ private static JsonReader readJSONFile(Context context) throws IOException {
         }
 
         String userAgent = Util.getUserAgent(context, "ClassicalMusicQuiz");
-        DataSource dataSource = new DefaultDataSource(context, null, userAgent, false);
+        DataSource dataSource = new DefaultDataSource(context, userAgent,1000,1000, false);
         DataSpec dataSpec = new DataSpec(Uri.parse(uri));
         InputStream inputStream = new DataSourceInputStream(dataSource, dataSpec);
 
@@ -190,7 +191,7 @@ private static JsonReader readJSONFile(Context context) throws IOException {
         try {
             reader = new JsonReader(new InputStreamReader(inputStream, "UTF-8"));
         } finally {
-            Util.closeQuietly(dataSource);
+            Util.closeQuietly((Closeable) dataSource);
         }
 
         return reader;
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index ce372fcb..da130a9b 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -11,7 +11,7 @@
  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.-->
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
@@ -82,4 +82,4 @@
         app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toRightOf="parent"
         app:layout_constraintTop_toBottomOf="@+id/highscoreText" />
-</android.support.constraint.ConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>
diff --git a/app/src/main/res/layout/activity_quiz.xml b/app/src/main/res/layout/activity_quiz.xml
index 29c580ce..e246be50 100644
--- a/app/src/main/res/layout/activity_quiz.xml
+++ b/app/src/main/res/layout/activity_quiz.xml
@@ -12,7 +12,7 @@
  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.-->
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
@@ -21,7 +21,7 @@
     tools:layout_editor_absoluteX="0dp"
     tools:layout_editor_absoluteY="81dp">
 
-    <com.google.android.exoplayer2.ui.SimpleExoPlayerView
+    <com.google.android.exoplayer2.ui.PlayerView
         android:id="@+id/playerView"
         android:layout_width="0dp"
         android:layout_height="0dp"
@@ -34,14 +34,12 @@
         android:layout_marginLeft="0dp"
         app:layout_constraintLeft_toLeftOf="parent" />
 
-    <android.support.constraint.Guideline
+    <androidx.constraintlayout.widget.Guideline
         android:id="@+id/horizontalHalf"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:orientation="horizontal"
-        app:layout_constraintGuide_percent="0.5"
-        tools:layout_editor_absoluteX="0dp"
-        tools:layout_editor_absoluteY="256dp" />
+        app:layout_constraintGuide_begin="366dp" />
 
     <Button
         android:id="@+id/buttonA"
@@ -81,4 +79,4 @@
         app:layout_constraintTop_toBottomOf="@+id/buttonB" />
 
   
-</android.support.constraint.ConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>
diff --git a/build.gradle b/build.gradle
index 1ea4bd05..34d0146c 100644
--- a/build.gradle
+++ b/build.gradle
@@ -2,10 +2,11 @@
 
 buildscript {
     repositories {
-        jcenter()
+        google()
+        mavenCentral()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.3.0'
+        classpath 'com.android.tools.build:gradle:7.0.3'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
@@ -14,7 +15,8 @@ buildscript {
 
 allprojects {
     repositories {
-        jcenter()
+        google()
+        mavenCentral()
     }
 }
 
diff --git a/gradle.properties b/gradle.properties
index 77ed50d5..9e3a2d10 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -9,6 +9,8 @@
 
 # Specifies the JVM arguments used for the daemon process.
 # The setting is particularly useful for tweaking memory settings.
+android.enableJetifier=true
+android.useAndroidX=true
 org.gradle.jvmargs=-Xmx1536m
 # When configured, Gradle will run in incubating parallel mode.
 # This option should only be used with decoupled projects. More details, visit
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 7aff1511..0314b0ae 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-3.3-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.0.2-all.zip

From 9b3bffbc17514ab3dcc6d2b41320417221260d3e Mon Sep 17 00:00:00 2001
From: Sagar <sagar.0dev@gmail.com>
Date: Mon, 24 Jan 2022 19:03:33 +0530
Subject: [PATCH 2/3] stable app

---
 app/src/main/AndroidManifest.xml                              | 3 ++-
 .../java/com/example/android/classicalmusicquiz/Sample.java   | 4 +++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 0426f4d5..c6aa8f78 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -22,7 +22,8 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/AppTheme">
-        <activity android:name=".MainActivity">
+        <activity android:name=".MainActivity"
+            android:exported="true">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
diff --git a/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java b/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java
index 35d73446..7a42b0f9 100644
--- a/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java
+++ b/app/src/main/java/com/example/android/classicalmusicquiz/Sample.java
@@ -16,6 +16,8 @@
 * limitations under the License.
 */
 
+import static com.google.android.exoplayer2.upstream.DataSourceUtil.closeQuietly;
+
 import android.content.Context;
 import android.content.res.AssetManager;
 import android.graphics.Bitmap;
@@ -191,7 +193,7 @@ private static JsonReader readJSONFile(Context context) throws IOException {
         try {
             reader = new JsonReader(new InputStreamReader(inputStream, "UTF-8"));
         } finally {
-            Util.closeQuietly((Closeable) dataSource);
+            closeQuietly(dataSource);
         }
 
         return reader;

From 63edb946749ccda1e9ed19ee2ccdd026b268e88b Mon Sep 17 00:00:00 2001
From: Sagar <sagar.0dev@gmail.com>
Date: Mon, 24 Jan 2022 20:27:11 +0530
Subject: [PATCH 3/3] develop_branch

---
 app/src/main/AndroidManifest.xml              |   6 +
 .../classicalmusicquiz/QuizActivity.java      | 170 +++++++++++++++++-
 app/src/main/res/drawable/ic_music_note.xml   |   9 +
 app/src/main/res/layout/activity_quiz.xml     |   4 +-
 .../res/layout/exo_playback_control_view.xml  |  75 ++++++++
 app/src/main/res/values/strings.xml           |   3 +
 6 files changed, 262 insertions(+), 5 deletions(-)
 create mode 100644 app/src/main/res/drawable/ic_music_note.xml
 create mode 100644 app/src/main/res/layout/exo_playback_control_view.xml

diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index c6aa8f78..2ca8df66 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -32,6 +32,12 @@
         </activity>
         <activity android:name=".QuizActivity"
             android:launchMode="singleTop"/>
+        <receiver android:name=".QuizActivity$MediaReceiver"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.MEDIA_BUTTON" />
+            </intent-filter>
+        </receiver>
     </application>
 
 </manifest>
\ No newline at end of file
diff --git a/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java b/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java
index e74ea442..9f01e61b 100644
--- a/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java
+++ b/app/src/main/java/com/example/android/classicalmusicquiz/QuizActivity.java
@@ -16,6 +16,10 @@
 
 package com.example.android.classicalmusicquiz;
 
+import android.app.NotificationManager;
+import android.app.PendingIntent;
+import android.content.BroadcastReceiver;
+import android.content.Context;
 import android.content.Intent;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
@@ -25,16 +29,22 @@
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
-import androidx.core.content.ContextCompat;
-import androidx.appcompat.app.AppCompatActivity;
+import android.support.v4.media.session.MediaSessionCompat;
+import android.support.v4.media.session.PlaybackStateCompat;
 import android.view.View;
 import android.widget.Button;
 import android.widget.Toast;
+
+import androidx.core.content.ContextCompat;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.media.app.NotificationCompat;
+import androidx.media.session.MediaButtonReceiver;
+import androidx.core.app.NotificationCompat.Builder;
+
 import com.google.android.exoplayer2.DefaultLoadControl;
 import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.LoadControl;
 import com.google.android.exoplayer2.Player;
-import com.google.android.exoplayer2.SimpleExoPlayer;
 import com.google.android.exoplayer2.extractor.DefaultExtractorsFactory;
 import com.google.android.exoplayer2.source.MediaSource;
 import com.google.android.exoplayer2.source.ProgressiveMediaSource;
@@ -53,12 +63,16 @@ public class QuizActivity extends AppCompatActivity implements View.OnClickListe
     private int[] mButtonIDs = {R.id.buttonA, R.id.buttonB, R.id.buttonC, R.id.buttonD};
     private ArrayList<Integer> mRemainingSampleIDs;
     private ArrayList<Integer> mQuestionSampleIDs;
+    private static final String TAG = QuizActivity.class.getSimpleName();
     private int mAnswerSampleID;
     private int mCurrentScore;
     private int mHighScore;
     private Button[] mButtons;
     private ExoPlayer mExoPlayer;
     private PlayerView mPlayerView;
+    private static MediaSessionCompat mMediaSession;
+    public static PlaybackStateCompat.Builder mStateBuilder;
+    private NotificationManager mNotificationManager;
 
 
     @Override
@@ -101,7 +115,10 @@ protected void onCreate(Bundle savedInstanceState) {
         // Initialize the buttons with the composers names.
         mButtons = initializeButtons(mQuestionSampleIDs);
 
+        initializeMediaSession();
+
         Sample answerSample = Sample.getSampleByID(this, mAnswerSampleID);
+
         if (answerSample == null) {
             Toast.makeText(this, getString(R.string.sample_not_found_error),
                     Toast.LENGTH_SHORT).show();
@@ -113,6 +130,43 @@ protected void onCreate(Bundle savedInstanceState) {
     }
 
 
+    /**
+     * Initializes the Media Session to be enabled with media buttons, transport controls, callbacks
+     * and media controller.
+     */
+    private void initializeMediaSession() {
+
+        // Create a MediaSessionCompat.
+        mMediaSession = new MediaSessionCompat(this, TAG);
+
+        // Enable callbacks from MediaButtons and TransportControls.
+        mMediaSession.setFlags(
+                MediaSessionCompat.FLAG_HANDLES_MEDIA_BUTTONS |
+                        MediaSessionCompat.FLAG_HANDLES_TRANSPORT_CONTROLS);
+
+        // Do not let MediaButtons restart the player when the app is not visible.
+        mMediaSession.setMediaButtonReceiver(null);
+
+        // Set an initial PlaybackState with ACTION_PLAY, so media buttons can start the player.
+        mStateBuilder = new PlaybackStateCompat.Builder()
+                .setActions(
+                        PlaybackStateCompat.ACTION_PLAY |
+                                PlaybackStateCompat.ACTION_PAUSE |
+                                PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS |
+                                PlaybackStateCompat.ACTION_PLAY_PAUSE);
+
+        mMediaSession.setPlaybackState(mStateBuilder.build());
+
+
+        // MySessionCallback has methods that handle callbacks from a media controller.
+        mMediaSession.setCallback(new MySessionCallback());
+
+        // Start the Media Session since the activity is active.
+        mMediaSession.setActive(true);
+
+    }
+
+
     /**
      * Initializes the button to the correct views, and sets the text to the composers names,
      * and set's the OnClick listener to the buttons.
@@ -135,6 +189,56 @@ private Button[] initializeButtons(ArrayList<Integer> answerSampleIDs) {
     }
 
 
+    /**
+     * Shows Media Style notification, with an action that depends on the current MediaSession
+     * PlaybackState.
+     * @param state The PlaybackState of the MediaSession.
+     */
+    private void showNotification(PlaybackStateCompat state) {
+        //no channelId created as it's not part of our course
+        androidx.core.app.NotificationCompat.Builder builder = new Builder(this,"");
+
+        int icon;
+        String play_pause;
+        if(state.getState() == PlaybackStateCompat.STATE_PLAYING){
+            icon = R.drawable.exo_controls_pause;
+            play_pause = getString(R.string.pause);
+        } else {
+            icon = R.drawable.exo_controls_play;
+            play_pause = getString(R.string.play);
+        }
+
+
+        androidx.core.app.NotificationCompat.Action playPauseAction =new androidx.core.app.NotificationCompat.Action(
+                icon, play_pause,
+                MediaButtonReceiver.buildMediaButtonPendingIntent(this,
+                        PlaybackStateCompat.ACTION_PLAY_PAUSE));
+
+        androidx.core.app.NotificationCompat.Action restartAction =new androidx.core.app.NotificationCompat
+                .Action(R.drawable.exo_controls_previous, getString(R.string.restart),
+                MediaButtonReceiver.buildMediaButtonPendingIntent
+                        (this, PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS));
+
+        PendingIntent contentPendingIntent = PendingIntent.getActivity
+                (this, 0, new Intent(this, QuizActivity.class), 0);
+
+        builder.setContentTitle(getString(R.string.guess))
+                .setContentText(getString(R.string.notification_text))
+                .setContentIntent(contentPendingIntent)
+                .setSmallIcon(R.drawable.ic_music_note)
+                .setVisibility(androidx.core.app.NotificationCompat.VISIBILITY_PUBLIC)
+                .addAction(restartAction)
+                .addAction(playPauseAction)
+                .setStyle(new NotificationCompat.MediaStyle()
+                        .setMediaSession(mMediaSession.getSessionToken())
+                        .setShowActionsInCompactView(0,1));
+
+
+        mNotificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
+        mNotificationManager.notify(0, builder.build());
+    }
+
+
     /**
      * Initialize ExoPlayer.
      * @param mediaUri The URI of the sample to play.
@@ -144,7 +248,6 @@ private void initializePlayer(Uri mediaUri) {
             // Create an instance of the ExoPlayer.
             TrackSelector trackSelector = new DefaultTrackSelector();
             LoadControl loadControl = new DefaultLoadControl();
-
             mExoPlayer = new ExoPlayer.Builder(this)
                     .setTrackSelector(trackSelector)
                     .setLoadControl(loadControl).build();
@@ -171,6 +274,7 @@ private void initializePlayer(Uri mediaUri) {
      * Release ExoPlayer.
      */
     private void releasePlayer() {
+        mNotificationManager.cancelAll();
         mExoPlayer.stop();
         mExoPlayer.release();
         mExoPlayer = null;
@@ -231,6 +335,7 @@ public void run() {
         }, CORRECT_ANSWER_DELAY_MILLIS);
     }
 
+
     /**
      * Disables the buttons and changes the background colors and player art to
      * show the correct answer.
@@ -265,5 +370,62 @@ private void showCorrectAnswer() {
     protected void onDestroy() {
         super.onDestroy();
         releasePlayer();
+        mMediaSession.setActive(false);
+    }
+
+
+    // ExoPlayer Event Listener
+    /**
+     * Method that is called when the ExoPlayer state changes. Used to update the MediaSession
+     * PlayBackState to keep in sync, and post the media notification.
+     * @param playWhenReady true if ExoPlayer is playing, false if it's paused.
+     * @param playbackState int describing the state of ExoPlayer. Can be STATE_READY, STATE_IDLE,
+     *                      STATE_BUFFERING, or STATE_ENDED.
+     */
+    @Override
+    public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
+        if ((playbackState == ExoPlayer.STATE_READY) && playWhenReady) {
+            mStateBuilder.setState(PlaybackStateCompat.STATE_PLAYING,
+                    mExoPlayer.getCurrentPosition(), 1f);
+        } else if ((playbackState == ExoPlayer.STATE_READY)) {
+            mStateBuilder.setState(PlaybackStateCompat.STATE_PAUSED,
+                    mExoPlayer.getCurrentPosition(), 1f);
+        }
+        mMediaSession.setPlaybackState(mStateBuilder.build());
+        showNotification(mStateBuilder.build());
+    }
+
+    /**
+     * Media Session Callbacks, where all external clients control the player.
+     */
+    public class MySessionCallback extends MediaSessionCompat.Callback {
+        @Override
+        public void onPlay() {
+            mExoPlayer.setPlayWhenReady(true);
+        }
+
+        @Override
+        public void onPause() {
+            mExoPlayer.setPlayWhenReady(false);
+        }
+
+        @Override
+        public void onSkipToPrevious() {
+            mExoPlayer.seekTo(0);
+        }
+    }
+
+    /**
+     * Broadcast Receiver registered to receive the MEDIA_BUTTON intent coming from clients.
+     */
+    public static class MediaReceiver extends BroadcastReceiver {
+
+        public MediaReceiver() {
+        }
+
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            MediaButtonReceiver.handleIntent(mMediaSession, intent);
+        }
     }
 }
diff --git a/app/src/main/res/drawable/ic_music_note.xml b/app/src/main/res/drawable/ic_music_note.xml
new file mode 100644
index 00000000..c6dae872
--- /dev/null
+++ b/app/src/main/res/drawable/ic_music_note.xml
@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24.0"
+    android:viewportHeight="24.0">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M12,3v10.55c-0.59,-0.34 -1.27,-0.55 -2,-0.55 -2.21,0 -4,1.79 -4,4s1.79,4 4,4 4,-1.79 4,-4V7h4V3h-6z"/>
+</vector>
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_quiz.xml b/app/src/main/res/layout/activity_quiz.xml
index e246be50..41d436db 100644
--- a/app/src/main/res/layout/activity_quiz.xml
+++ b/app/src/main/res/layout/activity_quiz.xml
@@ -39,7 +39,9 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:orientation="horizontal"
-        app:layout_constraintGuide_begin="366dp" />
+        app:layout_constraintGuide_percent="0.5"
+        tools:layout_editor_absoluteX="0dp"
+        tools:layout_editor_absoluteY="256dp" />
 
     <Button
         android:id="@+id/buttonA"
diff --git a/app/src/main/res/layout/exo_playback_control_view.xml b/app/src/main/res/layout/exo_playback_control_view.xml
new file mode 100644
index 00000000..97c2be42
--- /dev/null
+++ b/app/src/main/res/layout/exo_playback_control_view.xml
@@ -0,0 +1,75 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2016 The Android Open Source Project
+     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
+          http://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.
+-->
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="bottom"
+    android:layoutDirection="ltr"
+    android:background="#CC000000"
+    android:orientation="vertical">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:gravity="center"
+        android:paddingTop="4dp"
+        android:orientation="horizontal">
+
+        <ImageButton android:id="@id/exo_prev"
+            style="@style/ExoMediaButton.Previous"/>
+
+        <ImageButton android:id="@id/exo_play"
+            style="@style/ExoMediaButton.Play"/>
+
+        <ImageButton android:id="@id/exo_pause"
+            style="@style/ExoMediaButton.Pause"/>
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="4dp"
+        android:gravity="center_vertical"
+        android:orientation="horizontal">
+
+        <TextView android:id="@id/exo_position"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textSize="14sp"
+            android:textStyle="bold"
+            android:paddingLeft="4dp"
+            android:paddingRight="4dp"
+            android:includeFontPadding="false"
+            android:textColor="#FFBEBEBE"/>
+
+        <SeekBar android:id="@id/exo_progress"
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:layout_height="32dp"
+            android:focusable="false"
+            style="?android:attr/progressBarStyleHorizontal"/>
+
+        <TextView android:id="@id/exo_duration"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:textSize="14sp"
+            android:textStyle="bold"
+            android:paddingLeft="4dp"
+            android:paddingRight="4dp"
+            android:includeFontPadding="false"
+            android:textColor="#FFBEBEBE"/>
+
+    </LinearLayout>
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index bbc7dd31..67ac2670 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -22,4 +22,7 @@
     <string name="notification_text">Press play to hear the piece!</string>
     <string name="sample_list_load_error">Error loading one or more samples!</string>
     <string name="sample_not_found_error">Sample not found!</string>
+    <string name="play">Play</string>
+    <string name="pause">Pause</string>
+    <string name="restart">Restart</string>
 </resources>