Merge branch 'nitehu-fix/equalizer_visualizer_init' into develop

ultrasonic/src/main/java/org/moire/ultrasonic/activity/DownloadActivity.java

@@ -49,10 +49,14 @@ import android.widget.SeekBar;
 import android.widget.TextView;
 import android.widget.ViewFlipper;
 
+import androidx.lifecycle.Observer;
+
 import com.mobeta.android.dslv.DragSortListView;
 
 import org.koin.java.KoinJavaComponent;
 import org.moire.ultrasonic.R;
+import org.moire.ultrasonic.audiofx.EqualizerController;
+import org.moire.ultrasonic.audiofx.VisualizerController;
 import org.moire.ultrasonic.data.ActiveServerProvider;
 import org.moire.ultrasonic.domain.MusicDirectory;
 import org.moire.ultrasonic.domain.MusicDirectory.Entry;
@@ -117,8 +121,6 @@ public class DownloadActivity extends SubsonicTabActivity implements OnGestureLi
 	private int swipeDistance;
 	private int swipeVelocity;
 	private VisualizerView visualizerView;
-	private boolean visualizerAvailable;
-	private boolean equalizerAvailable;
 	private boolean jukeboxAvailable;
 	private SilentBackgroundTask<Void> onProgressChangedTask;
 	LinearLayout visualizerViewLayout;
@@ -133,6 +135,9 @@ public class DownloadActivity extends SubsonicTabActivity implements OnGestureLi
 	private Drawable hollowStar;
 	private Drawable fullStar;
 
+	private boolean isEqualizerAvailable;
+	private boolean isVisualizerAvailable;
+
 	/**
 	 * Called when the activity is first created.
 	 */
@@ -506,8 +511,55 @@ public class DownloadActivity extends SubsonicTabActivity implements OnGestureLi
 			mediaPlayerController.setShufflePlayEnabled(true);
 		}
 
-		visualizerAvailable = (mediaPlayerController != null) && (mediaPlayerController.getVisualizerController() != null);
-		equalizerAvailable = (mediaPlayerController != null) && (mediaPlayerController.getEqualizerController() != null);
+		visualizerViewLayout.setVisibility(View.GONE);
+		VisualizerController.get().observe(this, new Observer<VisualizerController>() {
+			@Override
+			public void onChanged(VisualizerController visualizerController) {
+				if (visualizerController != null) {
+					Timber.d("VisualizerController Observer.onChanged received controller");
+					visualizerView = new VisualizerView(DownloadActivity.this);
+					visualizerViewLayout.addView(visualizerView, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT));
+
+					if (!visualizerView.isActive())
+					{
+						visualizerViewLayout.setVisibility(View.GONE);
+					}
+					else
+					{
+						visualizerViewLayout.setVisibility(View.VISIBLE);
+					}
+
+					visualizerView.setOnTouchListener(new View.OnTouchListener()
+					{
+						@Override
+						public boolean onTouch(final View view, final MotionEvent motionEvent)
+						{
+							visualizerView.setActive(!visualizerView.isActive());
+							getMediaPlayerController().setShowVisualization(visualizerView.isActive());
+							return true;
+						}
+					});
+					isVisualizerAvailable = true;
+				} else {
+					Timber.d("VisualizerController Observer.onChanged has no controller");
+					visualizerViewLayout.setVisibility(View.GONE);
+					isVisualizerAvailable = false;
+				}
+			}
+		});
+
+		EqualizerController.get().observe(this, new Observer<EqualizerController>() {
+			@Override
+			public void onChanged(EqualizerController equalizerController) {
+				if (equalizerController != null) {
+					Timber.d("EqualizerController Observer.onChanged received controller");
+					isEqualizerAvailable = true;
+				} else {
+					Timber.d("EqualizerController Observer.onChanged has no controller");
+					isEqualizerAvailable = false;
+				}
+			}
+		});
 
 		new Thread(new Runnable()
 		{
@@ -528,36 +580,6 @@ public class DownloadActivity extends SubsonicTabActivity implements OnGestureLi
 
 		final View nowPlayingMenuItem = findViewById(R.id.menu_now_playing);
 		menuDrawer.setActiveView(nowPlayingMenuItem);
-
-		if (visualizerAvailable)
-		{
-			visualizerView = new VisualizerView(this);
-			visualizerViewLayout.addView(visualizerView, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT));
-
-			if (!visualizerView.isActive())
-			{
-				visualizerViewLayout.setVisibility(View.GONE);
-			}
-			else
-			{
-				visualizerViewLayout.setVisibility(View.VISIBLE);
-			}
-
-			visualizerView.setOnTouchListener(new View.OnTouchListener()
-			{
-				@Override
-				public boolean onTouch(final View view, final MotionEvent motionEvent)
-				{
-					visualizerView.setActive(!visualizerView.isActive());
-					getMediaPlayerController().setShowVisualization(visualizerView.isActive());
-					return true;
-				}
-			});
-		}
-		else
-		{
-			visualizerViewLayout.setVisibility(View.GONE);
-		}
 	}
 
 	@Override
@@ -768,14 +790,14 @@ public class DownloadActivity extends SubsonicTabActivity implements OnGestureLi
 
 		if (equalizerMenuItem != null)
 		{
-			equalizerMenuItem.setEnabled(equalizerAvailable);
-			equalizerMenuItem.setVisible(equalizerAvailable);
+			equalizerMenuItem.setEnabled(isEqualizerAvailable);
+			equalizerMenuItem.setVisible(isEqualizerAvailable);
 		}
 
 		if (visualizerMenuItem != null)
 		{
-			visualizerMenuItem.setEnabled(visualizerAvailable);
-			visualizerMenuItem.setVisible(visualizerAvailable);
+			visualizerMenuItem.setEnabled(isVisualizerAvailable);
+			visualizerMenuItem.setVisible(isVisualizerAvailable);
 		}
 
 		final MediaPlayerController mediaPlayerController = getMediaPlayerController();

ultrasonic/src/main/java/org/moire/ultrasonic/activity/EqualizerActivity.java

@@ -30,6 +30,8 @@ import android.widget.LinearLayout;
 import android.widget.SeekBar;
 import android.widget.TextView;
 
+import androidx.lifecycle.Observer;
+
 import org.moire.ultrasonic.R;
 import org.moire.ultrasonic.audiofx.EqualizerController;
 import org.moire.ultrasonic.service.MediaPlayerController;
@@ -38,6 +40,7 @@ import java.util.HashMap;
 import java.util.Map;
 
 import kotlin.Lazy;
+import timber.log.Timber;
 
 import static org.koin.java.KoinJavaComponent.inject;
 
@@ -55,21 +58,34 @@ public class EqualizerActivity extends ResultActivity
 	private EqualizerController equalizerController;
 	private Equalizer equalizer;
 
-	private Lazy<MediaPlayerController> mediaPlayerControllerLazy = inject(MediaPlayerController.class);
-
 	@Override
 	public void onCreate(Bundle bundle)
 	{
 		super.onCreate(bundle);
 		setContentView(R.layout.equalizer);
 
-		setup();
+		EqualizerController.get().observe(this, new Observer<EqualizerController>() {
+			@Override
+			public void onChanged(EqualizerController controller) {
+				if (controller != null) {
+					Timber.d("EqualizerController Observer.onChanged received controller");
+					equalizerController = controller;
+					equalizer = controller.equalizer;
+					setup();
+				} else {
+					Timber.d("EqualizerController Observer.onChanged has no controller");
+					equalizerController = null;
+					equalizer = null;
+				}
+			}
+		});
 	}
 
 	@Override
 	protected void onPause()
 	{
 		super.onPause();
+		if (equalizerController == null) return;
 		equalizerController.saveSettings();
 	}
 
@@ -77,16 +93,13 @@ public class EqualizerActivity extends ResultActivity
 	protected void onResume()
 	{
 		super.onResume();
-		if (equalizerController == null)
-		{
-			setup();
-		}
 	}
 
 	@Override
 	public void onCreateContextMenu(ContextMenu menu, View view, ContextMenu.ContextMenuInfo menuInfo)
 	{
 		super.onCreateContextMenu(menu, view, menuInfo);
+		if (equalizer == null) return;
 
 		short currentPreset;
 		try
@@ -112,6 +125,7 @@ public class EqualizerActivity extends ResultActivity
 	@Override
 	public boolean onContextItemSelected(MenuItem menuItem)
 	{
+		if (equalizer == null) return true;
 		try
 		{
 			short preset = (short) menuItem.getItemId();
@@ -128,9 +142,6 @@ public class EqualizerActivity extends ResultActivity
 
 	private void setup()
 	{
-		equalizerController = mediaPlayerControllerLazy.getValue().getEqualizerController();
-		equalizer = equalizerController.getEqualizer();
-
 		initEqualizer();
 
 		final View presetButton = findViewById(R.id.equalizer_preset);
@@ -158,12 +169,14 @@ public class EqualizerActivity extends ResultActivity
 
 	private void setEqualizerEnabled(boolean enabled)
 	{
+		if (equalizer == null) return;
 		equalizer.setEnabled(enabled);
 		updateBars();
 	}
 
 	private void updateBars()
 	{
+		if (equalizer == null) return;
 		try
 		{
 			for (Map.Entry<Short, SeekBar> entry : bars.entrySet())
@@ -183,6 +196,7 @@ public class EqualizerActivity extends ResultActivity
 
 	private void initEqualizer()
 	{
+		if (equalizer == null) return;
 		LinearLayout layout = (LinearLayout) findViewById(R.id.equalizer_layout);
 
 		try

ultrasonic/src/main/java/org/moire/ultrasonic/audiofx/EqualizerController.java

@@ -21,6 +21,10 @@ package org.moire.ultrasonic.audiofx;
 import android.content.Context;
 import android.media.MediaPlayer;
 import android.media.audiofx.Equalizer;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
 import timber.log.Timber;
 
 import org.moire.ultrasonic.util.FileUtil;
@@ -35,61 +39,83 @@ import java.io.Serializable;
  */
 public class EqualizerController
 {
-	private final Context context;
-	private Equalizer equalizer;
-	private boolean released;
+	private static Boolean available = null;
+	private static MutableLiveData<EqualizerController> instance = new MutableLiveData<>();
+
+	private Context context;
+	public Equalizer equalizer;
 	private int audioSessionId;
 
-	// Class initialization fails when this throws an exception.
-	static
+	/**
+	 * Retrieves the EqualizerController as LiveData
+	 */
+	public static LiveData<EqualizerController> get()
 	{
-		try
-		{
-			Class.forName("android.media.audiofx.Equalizer");
-		}
-		catch (Exception ex)
-		{
-			throw new RuntimeException(ex);
-		}
+		return instance;
 	}
 
 	/**
-	 * Throws an exception if the {@link Equalizer} class is not available.
+	 * Initializes the EqualizerController instance with a MediaPlayer
 	 */
-	public static void checkAvailable() throws Throwable
+	public static void create(Context context, MediaPlayer mediaPlayer)
 	{
-		// Calling here forces class initialization.
-	}
+		if (mediaPlayer == null) return;
+		if (!isAvailable()) return;
 
-	public EqualizerController(Context context, MediaPlayer mediaPlayer)
-	{
-		this.context = context;
+		EqualizerController controller = new EqualizerController();
+		controller.context = context;
 
 		try
 		{
-			if (mediaPlayer == null)
-			{
-				return;
-			}
+			controller.audioSessionId = mediaPlayer.getAudioSessionId();
+			controller.equalizer = new Equalizer(0, controller.audioSessionId);
+			controller.loadSettings();
 
-			audioSessionId = mediaPlayer.getAudioSessionId();
-			equalizer = new Equalizer(0, audioSessionId);
+			instance.postValue(controller);
 		}
 		catch (Throwable x)
 		{
-			equalizer = null;
 			Timber.w(x, "Failed to create equalizer.");
 		}
 	}
 
-	public void saveSettings()
+	/**
+	 * Releases the EqualizerController instance when the underlying MediaPlayer is no longer available
+	 */
+	public static void release()
 	{
+		EqualizerController controller = instance.getValue();
+		if (controller == null) return;
+
+		controller.equalizer.release();
+		instance.postValue(null);
+	}
+
+	/**
+	 * Checks if the {@link Equalizer} class is available.
+	 */
+	private static boolean isAvailable()
+	{
+		if (available != null) return available;
 		try
 		{
-			if (isAvailable())
-			{
-				FileUtil.serialize(context, new EqualizerSettings(equalizer), "equalizer.dat");
-			}
+			Class.forName("android.media.audiofx.Equalizer");
+			available = true;
+		}
+		catch (Exception ex)
+		{
+			Timber.i(ex, "CheckAvailable received an exception getting class for the Equalizer");
+			available = false;
+		}
+		return available;
+	}
+
+	public void saveSettings()
+	{
+		if (!available) return;
+		try
+		{
+			FileUtil.serialize(context, new EqualizerSettings(equalizer), "equalizer.dat");
 		}
 		catch (Throwable x)
 		{
@@ -99,16 +125,14 @@ public class EqualizerController
 
 	public void loadSettings()
 	{
+		if (!available) return;
 		try
 		{
-			if (isAvailable())
-			{
-				EqualizerSettings settings = FileUtil.deserialize(context, "equalizer.dat");
+			EqualizerSettings settings = FileUtil.deserialize(context, "equalizer.dat");
 
-				if (settings != null)
-				{
-					settings.apply(equalizer);
-				}
+			if (settings != null)
+			{
+				settings.apply(equalizer);
 			}
 		}
 		catch (Throwable x)
@@ -117,46 +141,8 @@ public class EqualizerController
 		}
 	}
 
-	public boolean isAvailable()
-	{
-		return equalizer != null;
-	}
-
-	public void release()
-	{
-		if (isAvailable())
-		{
-			released = true;
-			equalizer.release();
-		}
-	}
-
-	public Equalizer getEqualizer()
-	{
-		if (released)
-		{
-			released = false;
-
-			try
-			{
-				equalizer = new Equalizer(0, audioSessionId);
-			}
-			catch (Throwable x)
-			{
-				equalizer = null;
-				Timber.w(x, "Failed to create equalizer.");
-			}
-		}
-
-		return equalizer;
-	}
-
 	private static class EqualizerSettings implements Serializable
 	{
-
-		/**
-		 *
-		 */
 		private static final long serialVersionUID = 626565082425206061L;
 		private final short[] bandLevels;
 		private short preset;

ultrasonic/src/main/java/org/moire/ultrasonic/audiofx/VisualizerController.java

@@ -20,6 +20,10 @@ package org.moire.ultrasonic.audiofx;
 
 import android.media.MediaPlayer;
 import android.media.audiofx.Visualizer;
+
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
 import timber.log.Timber;
 
 /**
@@ -31,89 +35,76 @@ import timber.log.Timber;
 public class VisualizerController
 {
 	private static final int PREFERRED_CAPTURE_SIZE = 128; // Must be a power of two.
+	private static Boolean available = null;
+	private static MutableLiveData<VisualizerController> instance = new MutableLiveData<>();
 
-	private Visualizer visualizer;
-	private boolean released;
+	public Visualizer visualizer;
 	private int audioSessionId;
 
-	// Class initialization fails when this throws an exception.
-	static
+	/**
+	 * Retrieves the VisualizerController as LiveData
+	 */
+	public static LiveData<VisualizerController> get()
 	{
-		try
-		{
-			Class.forName("android.media.audiofx.Visualizer");
-		}
-		catch (Exception ex)
-		{
-			throw new RuntimeException(ex);
-		}
+		return instance;
 	}
 
 	/**
-	 * Throws an exception if the {@link Visualizer} class is not available.
+	 * Initializes the VisualizerController instance with a MediaPlayer
 	 */
-	public static void checkAvailable() throws Throwable
+	public static void create(MediaPlayer mediaPlayer)
 	{
-		// Calling here forces class initialization.
-	}
+		if (mediaPlayer == null) return;
+		if (!isAvailable()) return;
+
+		VisualizerController controller = new VisualizerController();
 
-	public VisualizerController(MediaPlayer mediaPlayer)
-	{
 		try
 		{
-			if (mediaPlayer == null)
-			{
-				return;
-			}
+			controller.audioSessionId = mediaPlayer.getAudioSessionId();
+			controller.visualizer = new Visualizer(controller.audioSessionId);
 
-			audioSessionId = mediaPlayer.getAudioSessionId();
-			visualizer = new Visualizer(audioSessionId);
+			int[] captureSizeRange = Visualizer.getCaptureSizeRange();
+			int captureSize = Math.max(PREFERRED_CAPTURE_SIZE, captureSizeRange[0]);
+			captureSize = Math.min(captureSize, captureSizeRange[1]);
+			controller.visualizer.setCaptureSize(captureSize);
+
+			instance.postValue(controller);
 		}
 		catch (Throwable x)
 		{
 			Timber.w(x, "Failed to create visualizer.");
 		}
-
-		if (visualizer != null)
-		{
-			int[] captureSizeRange = Visualizer.getCaptureSizeRange();
-			int captureSize = Math.max(PREFERRED_CAPTURE_SIZE, captureSizeRange[0]);
-			captureSize = Math.min(captureSize, captureSizeRange[1]);
-			visualizer.setCaptureSize(captureSize);
-		}
 	}
 
-	public boolean isAvailable()
+	/**
+	 * Releases the VisualizerController instance when the underlying MediaPlayer is no longer available
+	 */
+	public static void release()
 	{
-		return visualizer != null;
+		VisualizerController controller = instance.getValue();
+		if (controller == null) return;
+
+		controller.visualizer.release();
+		instance.postValue(null);
 	}
 
-	public void release()
+	/**
+	 * Checks if the {@link Visualizer} class is available.
+	 */
+	private static boolean isAvailable()
 	{
-		if (isAvailable())
+		if (available != null) return available;
+		try
 		{
-			visualizer.release();
-			released = true;
+			Class.forName("android.media.audiofx.Visualizer");
+			available = true;
 		}
-	}
-
-	public Visualizer getVisualizer()
-	{
-		if (released)
+		catch (Exception ex)
 		{
-			released = false;
-
-			try
-			{
-				visualizer = new Visualizer(audioSessionId);
-			}
-			catch (Throwable x)
-			{
-				visualizer = null;
-				Timber.w(x, "Failed to create visualizer.");
-			}
+			Timber.i(ex, "CheckAvailable received an exception getting class for the Visualizer");
+			available = false;
 		}
-
-		return visualizer;
+		return available;
 	}
 }

ultrasonic/src/main/java/org/moire/ultrasonic/service/LocalMediaPlayer.java

@@ -55,9 +55,6 @@ public class LocalMediaPlayer
     public Runnable onPrepared;
     public Runnable onNextSongRequested;
 
-    public static boolean equalizerAvailable;
-    public static boolean visualizerAvailable;
-
     public PlayerState playerState = IDLE;
     public DownloadFile currentPlaying;
     public DownloadFile nextPlaying;
@@ -77,8 +74,6 @@ public class LocalMediaPlayer
     private AudioManager audioManager;
     private RemoteControlClient remoteControlClient;
 
-    private EqualizerController equalizerController;
-    private VisualizerController visualizerController;
     private CancellableTask bufferTask;
     private PositionCache positionCache;
     private int secondaryProgress = -1;
@@ -86,32 +81,6 @@ public class LocalMediaPlayer
     private final AudioFocusHandler audioFocusHandler;
     private final Context context;
 
-    static
-    {
-        try
-        {
-            EqualizerController.checkAvailable();
-            equalizerAvailable = true;
-        }
-        catch (Throwable t)
-        {
-            equalizerAvailable = false;
-        }
-    }
-
-    static
-    {
-        try
-        {
-            VisualizerController.checkAvailable();
-            visualizerAvailable = true;
-        }
-        catch (Throwable t)
-        {
-            visualizerAvailable = false;
-        }
-    }
-
     public LocalMediaPlayer(AudioFocusHandler audioFocusHandler, Context context)
     {
         this.audioFocusHandler = audioFocusHandler;
@@ -164,6 +133,15 @@ public class LocalMediaPlayer
             }
         }).start();
 
+        // Create Equalizer and Visualizer on a new thread as this can potentially take some time
+        new Thread(new Runnable() {
+            @Override
+            public void run() {
+                EqualizerController.create(context, mediaPlayer);
+                VisualizerController.create(mediaPlayer);
+            }
+        }).start();
+
         PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
         wakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, this.getClass().getName());
         wakeLock.setReferenceCounted(false);
@@ -172,28 +150,6 @@ public class LocalMediaPlayer
         Util.registerMediaButtonEventReceiver(context, true);
         setUpRemoteControlClient();
 
-        if (equalizerAvailable)
-        {
-            equalizerController = new EqualizerController(context, mediaPlayer);
-            if (!equalizerController.isAvailable())
-            {
-                equalizerController = null;
-            }
-            else
-            {
-                equalizerController.loadSettings();
-            }
-        }
-
-        if (visualizerAvailable)
-        {
-            visualizerController = new VisualizerController(mediaPlayer);
-            if (!visualizerController.isAvailable())
-            {
-                visualizerController = null;
-            }
-        }
-
         Timber.i("LocalMediaPlayer created");
     }
 
@@ -208,6 +164,9 @@ public class LocalMediaPlayer
             i.putExtra(AudioEffect.EXTRA_PACKAGE_NAME, context.getPackageName());
             context.sendBroadcast(i);
 
+            EqualizerController.release();
+            VisualizerController.release();
+
             mediaPlayer.release();
             if (nextMediaPlayer != null)
             {
@@ -216,16 +175,6 @@ public class LocalMediaPlayer
 
             mediaPlayerLooper.quit();
 
-            if (equalizerController != null)
-            {
-                equalizerController.release();
-            }
-
-            if (visualizerController != null)
-            {
-                visualizerController.release();
-            }
-
             if (bufferTask != null)
             {
                 bufferTask.cancel();
@@ -249,36 +198,6 @@ public class LocalMediaPlayer
         Timber.i("LocalMediaPlayer destroyed");
     }
 
-    public EqualizerController getEqualizerController()
-    {
-        if (equalizerAvailable && equalizerController == null)
-        {
-            equalizerController = new EqualizerController(context, mediaPlayer);
-            if (!equalizerController.isAvailable())
-            {
-                equalizerController = null;
-            }
-            else
-            {
-                equalizerController.loadSettings();
-            }
-        }
-        return equalizerController;
-    }
-
-    public VisualizerController getVisualizerController()
-    {
-        if (visualizerAvailable && visualizerController == null)
-        {
-            visualizerController = new VisualizerController(mediaPlayer);
-            if (!visualizerController.isAvailable())
-            {
-                visualizerController = null;
-            }
-        }
-        return visualizerController;
-    }
-
     public synchronized void setPlayerState(final PlayerState playerState)
     {
         Timber.i("%s -> %s (%s)", this.playerState.name(), playerState.name(), currentPlaying);

ultrasonic/src/main/java/org/moire/ultrasonic/service/MediaPlayerController.java

@@ -93,10 +93,6 @@ public interface MediaPlayerController
 
 	String getSuggestedPlaylistName();
 
-	EqualizerController getEqualizerController();
-
-	VisualizerController getVisualizerController();
-
 	boolean isJukeboxEnabled();
 
 	boolean isJukeboxAvailable();

ultrasonic/src/main/java/org/moire/ultrasonic/service/MediaPlayerControllerImpl.java

@@ -510,22 +510,6 @@ public class MediaPlayerControllerImpl implements MediaPlayerController
 		return suggestedPlaylistName;
 	}
 
-	@Override
-	public EqualizerController getEqualizerController()
-	{
-		MediaPlayerService mediaPlayerService = MediaPlayerService.getRunningInstance();
-		if (mediaPlayerService == null) return null;
-		return localMediaPlayer.getEqualizerController();
-	}
-
-	@Override
-	public VisualizerController getVisualizerController()
-	{
-		MediaPlayerService mediaPlayerService = MediaPlayerService.getRunningInstance();
-		if (mediaPlayerService == null) return null;
-		return localMediaPlayer.getVisualizerController();
-	}
-
 	@Override
 	public boolean isJukeboxEnabled()
 	{

ultrasonic/src/main/java/org/moire/ultrasonic/view/VisualizerView.java

@@ -25,11 +25,15 @@ import android.graphics.Paint;
 import android.media.audiofx.Visualizer;
 import android.view.View;
 
+import androidx.lifecycle.LifecycleOwner;
+import androidx.lifecycle.Observer;
+
 import org.moire.ultrasonic.audiofx.VisualizerController;
 import org.moire.ultrasonic.domain.PlayerState;
 import org.moire.ultrasonic.service.MediaPlayerController;
 
 import kotlin.Lazy;
+import timber.log.Timber;
 
 import static org.koin.java.KoinJavaComponent.inject;
 
@@ -45,20 +49,35 @@ public class VisualizerView extends View
 	private static final int PREFERRED_CAPTURE_RATE_MILLIHERTZ = 20000;
 
 	private final Paint paint = new Paint();
+	private Lazy<MediaPlayerController> mediaPlayerControllerLazy = inject(MediaPlayerController.class);
 
 	private byte[] data;
 	private float[] points;
 	private boolean active;
+	private Visualizer visualizer;
 
-	private Lazy<MediaPlayerController> mediaPlayerControllerLazy = inject(MediaPlayerController.class);
-
-	public VisualizerView(Context context)
+	public VisualizerView(final Context context)
 	{
 		super(context);
 
 		paint.setStrokeWidth(2f);
 		paint.setAntiAlias(true);
 		paint.setColor(Color.rgb(0, 153, 204));
+
+		VisualizerController.get().observe((LifecycleOwner) context, new Observer<VisualizerController>() {
+			@Override
+			public void onChanged(VisualizerController controller) {
+				if (controller != null) {
+					Timber.d("VisualizerController Observer.onChanged received controller");
+					visualizer = controller.visualizer;
+					setActive(true);
+				} else {
+					Timber.d("VisualizerController Observer.onChanged has no controller");
+					visualizer = null;
+					setActive(false);
+				}
+			}
+		});
 	}
 
 	public boolean isActive()
@@ -66,15 +85,9 @@ public class VisualizerView extends View
 		return active;
 	}
 
-	public void setActive(boolean active)
+	public void setActive(boolean value)
 	{
-		this.active = active;
-		Visualizer visualizer = getVizualizer();
-		if (visualizer == null)
-		{
-			return;
-		}
-
+		active = value;
 		int captureRate = Math.min(PREFERRED_CAPTURE_RATE_MILLIHERTZ, Visualizer.getMaxCaptureRate());
 		if (active)
 		{
@@ -94,19 +107,13 @@ public class VisualizerView extends View
 		}
 		else
 		{
-			visualizer.setDataCaptureListener(null, captureRate, false, false);
+			if (visualizer != null) visualizer.setDataCaptureListener(null, captureRate, false, false);
 		}
 
-		visualizer.setEnabled(active);
+		if (visualizer != null) visualizer.setEnabled(active);
 		invalidate();
 	}
 
-	private Visualizer getVizualizer()
-	{
-		VisualizerController visualizerController = mediaPlayerControllerLazy.getValue().getVisualizerController();
-		return visualizerController == null ? null : visualizerController.getVisualizer();
-	}
-
 	private void updateVisualizer(byte[] waveform)
 	{
 		this.data = waveform;