Replace Handlers by lightweight callbacks

src/org/kde/kdeconnect/Plugins/MprisPlugin/MprisMediaSession.java

@@ -14,9 +14,6 @@ import android.content.SharedPreferences;
 import android.graphics.Bitmap;
 import android.media.AudioManager;
 import android.os.Build;
-import android.os.Handler;
-import android.os.Looper;
-import android.os.Message;
 import android.preference.PreferenceManager;
 import android.service.notification.StatusBarNotification;
 import android.support.v4.media.MediaMetadataCompat;
@@ -77,13 +74,6 @@ public class MprisMediaSession implements
     private Context context;
     private MediaSessionCompat mediaSession;
 
-    //Callback for mpris plugin updates
-    private final Handler mediaNotificationHandler = new Handler(Looper.getMainLooper()) {
-        @Override
-        public void handleMessage(Message msg) {
-            updateMediaNotification();
-        }
-    };
     //Callback for control via the media session API
     private final MediaSessionCompat.Callback mediaSessionCallback = new MediaSessionCompat.Callback() {
         @Override
@@ -134,8 +124,8 @@ public class MprisMediaSession implements
         context = _context;
         mprisDevices.add(device);
 
-        mpris.setPlayerListUpdatedHandler("media_notification", mediaNotificationHandler);
+        mpris.setPlayerListUpdatedHandler("media_notification", this::updateMediaNotification);
-        mpris.setPlayerStatusUpdatedHandler("media_notification", mediaNotificationHandler);
+        mpris.setPlayerStatusUpdatedHandler("media_notification", this::updateMediaNotification);
 
         NotificationReceiver.RunCommand(context, service -> {
 

src/org/kde/kdeconnect/Plugins/MprisPlugin/MprisNowPlayingFragment.java

@@ -9,7 +9,6 @@ import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
-import android.os.Message;
 import android.preference.PreferenceManager;
 import android.text.TextUtils;
 import android.view.LayoutInflater;
@@ -213,80 +212,71 @@ public class MprisNowPlayingFragment extends Fragment implements VolumeKeyListen
         BackgroundService.RunWithPlugin(requireContext(), deviceId, MprisPlugin.class, mpris -> {
             targetPlayer = mpris.getPlayerStatus(targetPlayerName);
 
-            mpris.setPlayerStatusUpdatedHandler("activity", new Handler() {
+            mpris.setPlayerStatusUpdatedHandler("activity", () -> requireActivity().runOnUiThread(() -> updatePlayerStatus(mpris)));
-                @Override
+            mpris.setPlayerListUpdatedHandler("activity", () -> {
-                public void handleMessage(Message msg) {
+                final List<String> playerList = mpris.getPlayerList();
-                    requireActivity().runOnUiThread(() -> updatePlayerStatus(mpris));
+                final ArrayAdapter<String> adapter = new ArrayAdapter<>(requireContext(),
-                }
+                        android.R.layout.simple_spinner_item,
-            });
+                        playerList.toArray(ArrayUtils.EMPTY_STRING_ARRAY)
+                );
 
-            mpris.setPlayerListUpdatedHandler("activity", new Handler() {
+                adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
-                @Override
+                requireActivity().runOnUiThread(() -> {
-                public void handleMessage(Message msg) {
+                    mprisControlBinding.playerSpinner.setAdapter(adapter);
-                    final List<String> playerList = mpris.getPlayerList();
-                    final ArrayAdapter<String> adapter = new ArrayAdapter<>(requireContext(),
-                            android.R.layout.simple_spinner_item,
-                            playerList.toArray(ArrayUtils.EMPTY_STRING_ARRAY)
-                    );
 
-                    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
+                    if (playerList.isEmpty()) {
-                    requireActivity().runOnUiThread(() -> {
+                        mprisControlBinding.noPlayers.setVisibility(View.VISIBLE);
-                        mprisControlBinding.playerSpinner.setAdapter(adapter);
+                        mprisControlBinding.playerSpinner.setVisibility(View.GONE);
+                        mprisControlBinding.nowPlayingTextview.setText("");
+                    } else {
+                        mprisControlBinding.noPlayers.setVisibility(View.GONE);
+                        mprisControlBinding.playerSpinner.setVisibility(View.VISIBLE);
+                    }
 
-                        if (playerList.isEmpty()) {
+                    mprisControlBinding.playerSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
-                            mprisControlBinding.noPlayers.setVisibility(View.VISIBLE);
+                        @Override
-                            mprisControlBinding.playerSpinner.setVisibility(View.GONE);
+                        public void onItemSelected(AdapterView<?> arg0, View arg1, int pos, long id) {
-                            mprisControlBinding.nowPlayingTextview.setText("");
-                        } else {
-                            mprisControlBinding.noPlayers.setVisibility(View.GONE);
-                            mprisControlBinding.playerSpinner.setVisibility(View.VISIBLE);
-                        }
 
-                        mprisControlBinding.playerSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
+                            if (pos >= playerList.size()) return;
-                            @Override
-                            public void onItemSelected(AdapterView<?> arg0, View arg1, int pos, long id) {
 
-                                if (pos >= playerList.size()) return;
+                            String player = playerList.get(pos);
-
+                            if (targetPlayer != null && player.equals(targetPlayer.getPlayer())) {
-                                String player = playerList.get(pos);
+                                return; //Player hasn't actually changed
-                                if (targetPlayer != null && player.equals(targetPlayer.getPlayer())) {
-                                    return; //Player hasn't actually changed
-                                }
-                                targetPlayer = mpris.getPlayerStatus(player);
-                                updatePlayerStatus(mpris);
-
-                                if (targetPlayer != null && targetPlayer.isPlaying()) {
-                                    MprisMediaSession.getInstance().playerSelected(targetPlayer);
-                                }
                             }
+                            targetPlayer = mpris.getPlayerStatus(player);
+                            updatePlayerStatus(mpris);
 
-                            @Override
+                            if (targetPlayer != null && targetPlayer.isPlaying()) {
-                            public void onNothingSelected(AdapterView<?> arg0) {
+                                MprisMediaSession.getInstance().playerSelected(targetPlayer);
-                                targetPlayer = null;
-                            }
-                        });
-
-                        if (targetPlayer == null) {
-                            //If no player is selected, try to select a playing player
-                            targetPlayer = mpris.getPlayingPlayer();
-                        }
-                        //Try to select the specified player
-                        if (targetPlayer != null) {
-                            int targetIndex = adapter.getPosition(targetPlayer.getPlayer());
-                            if (targetIndex >= 0) {
-                                mprisControlBinding.playerSpinner.setSelection(targetIndex);
-                            } else {
-                                targetPlayer = null;
                             }
                         }
-                        //If no player selected, select the first one (if any)
+
-                        if (targetPlayer == null && !playerList.isEmpty()) {
+                        @Override
-                            targetPlayer = mpris.getPlayerStatus(playerList.get(0));
+                        public void onNothingSelected(AdapterView<?> arg0) {
-                            mprisControlBinding.playerSpinner.setSelection(0);
+                            targetPlayer = null;
                         }
-                        updatePlayerStatus(mpris);
                     });
-                }
+
+                    if (targetPlayer == null) {
+                        //If no player is selected, try to select a playing player
+                        targetPlayer = mpris.getPlayingPlayer();
+                    }
+                    //Try to select the specified player
+                    if (targetPlayer != null) {
+                        int targetIndex = adapter.getPosition(targetPlayer.getPlayer());
+                        if (targetIndex >= 0) {
+                            mprisControlBinding.playerSpinner.setSelection(targetIndex);
+                        } else {
+                            targetPlayer = null;
+                        }
+                    }
+                    //If no player selected, select the first one (if any)
+                    if (targetPlayer == null && !playerList.isEmpty()) {
+                        targetPlayer = mpris.getPlayerStatus(playerList.get(0));
+                        mprisControlBinding.playerSpinner.setSelection(0);
+                    }
+                    updatePlayerStatus(mpris);
+                });
             });
         });
     }

src/org/kde/kdeconnect/Plugins/MprisPlugin/MprisPlugin.java

@@ -227,14 +227,18 @@ public class MprisPlugin extends Plugin {
         }
     }
 
+    public interface Callback {
+        void callback();
+    }
+
     public final static String DEVICE_ID_KEY = "deviceId";
     private final static String PACKET_TYPE_MPRIS = "kdeconnect.mpris";
     private final static String PACKET_TYPE_MPRIS_REQUEST = "kdeconnect.mpris.request";
 
     private final ConcurrentHashMap<String, MprisPlayer> players = new ConcurrentHashMap<>();
     private boolean supportAlbumArtPayload = false;
-    private final ConcurrentHashMap<String, Handler> playerStatusUpdated = new ConcurrentHashMap<>();
+    private final ConcurrentHashMap<String, Callback> playerStatusUpdated = new ConcurrentHashMap<>();
-    private final ConcurrentHashMap<String, Handler> playerListUpdated = new ConcurrentHashMap<>();
+    private final ConcurrentHashMap<String, Callback> playerListUpdated = new ConcurrentHashMap<>();
 
     @Override
     public String getDisplayName() {
@@ -349,7 +353,7 @@ public class MprisPlugin extends Plugin {
 
                 for (String key : playerStatusUpdated.keySet()) {
                     try {
-                        playerStatusUpdated.get(key).dispatchMessage(new Message());
+                        playerStatusUpdated.get(key).callback();
                     } catch (Exception e) {
                         Log.e("MprisControl", "Exception", e);
                         playerStatusUpdated.remove(key);
@@ -390,7 +394,7 @@ public class MprisPlugin extends Plugin {
             if (!equals) {
                 for (String key : playerListUpdated.keySet()) {
                     try {
-                        playerListUpdated.get(key).dispatchMessage(new Message());
+                        playerListUpdated.get(key).callback();
                     } catch (Exception e) {
                         Log.e("MprisControl", "Exception", e);
                         playerListUpdated.remove(key);
@@ -412,20 +416,19 @@ public class MprisPlugin extends Plugin {
         return new String[]{PACKET_TYPE_MPRIS_REQUEST};
     }
 
-    public void setPlayerStatusUpdatedHandler(String id, Handler h) {
+    public void setPlayerStatusUpdatedHandler(String id, Callback h) {
         playerStatusUpdated.put(id, h);
-
+        h.callback();
-        h.dispatchMessage(new Message());
     }
 
     public void removePlayerStatusUpdatedHandler(String id) {
         playerStatusUpdated.remove(id);
     }
 
-    public void setPlayerListUpdatedHandler(String id, Handler h) {
+    public void setPlayerListUpdatedHandler(String id, Callback h) {
         playerListUpdated.put(id, h);
 
-        h.dispatchMessage(new Message());
+        h.callback();
     }
 
     public void removePlayerListUpdatedHandler(String id) {
@@ -500,7 +503,7 @@ public class MprisPlugin extends Plugin {
         if (players.values().stream().anyMatch(player -> url.equals(player.albumArtUrl))) {
             for (String key : playerStatusUpdated.keySet()) {
                 try {
-                    playerStatusUpdated.get(key).dispatchMessage(new Message());
+                    playerStatusUpdated.get(key).callback();
                 } catch (Exception e) {
                     Log.e("MprisControl", "Exception", e);
                     playerStatusUpdated.remove(key);