android/src/org/rockbox/Helper/MediaButtonReceiver.java

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2010 Thomas Martitz
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 package org.rockbox.Helper;
  23
  24 import org.rockbox.RockboxFramebuffer;
  25 import org.rockbox.RockboxService;
  26 import android.content.BroadcastReceiver;
  27 import android.content.ComponentName;
  28 import android.content.Context;
  29 import android.content.Intent;
  30 import android.content.IntentFilter;
  31 import android.media.AudioManager;
  32 import android.view.KeyEvent;
  33
  34 public class MediaButtonReceiver
  35 {
  36     /* A note on the API being used. 2.2 introduces a new and sane API
  37      * for handling multimedia button presses
  38      * http://android-developers.blogspot.com/2010/06/allowing-applications-to-play-nicer.html
  39      *
  40      * the old API is flawed. It doesn't have management for
  41      * concurrent media apps
  42      *
  43      * if multiple media apps are running
  44      * probably all of them want to respond to media keys
  45      *
  46      * it's not clear which app wins, it depends on the
  47      * priority set for the IntentFilter (see below)
  48      *
  49      * so this all might or might not work on < 2.2 */
  50
  51     IMultiMediaReceiver api;
  52
  53     public MediaButtonReceiver(Context c)
  54     {
  55         try {
  56             api = new NewApi(c);
  57         } catch (Throwable t) {
  58             /* Throwable includes Exception and the expected
  59              * NoClassDefFoundError */
  60             api = new OldApi(c);
  61             Logger.i("MediaButtonReceiver: Falling back to compatibility API");
  62         }
  63     }
  64
  65     public void register()
  66     {
  67         api.register();
  68     }
  69
  70     public void unregister()
  71     {
  72         api.unregister();
  73     }
  74
  75     /* helper class for the manifest */
  76     public static class MediaReceiver extends BroadcastReceiver
  77     {
  78         private void startService(Context c, Intent baseIntent)
  79         {
  80             baseIntent.setClass(c, RockboxService.class);
  81             c.startService(baseIntent);
  82         }
  83         @Override
  84         public void onReceive(Context context, Intent intent)
  85         {
  86             if (Intent.ACTION_MEDIA_BUTTON.equals(intent.getAction()))
  87             {
  88                 KeyEvent key = (KeyEvent)intent.getParcelableExtra(Intent.EXTRA_KEY_EVENT);
  89                 if (key.getAction() == KeyEvent.ACTION_UP)
  90                 {   /* pass the pressed key to Rockbox, starting it if needed */
  91                     RockboxService s = RockboxService.get_instance();
  92                     if (s == null || !s.isRockboxRunning())
  93                         startService(context, intent);
  94                     else if (RockboxFramebuffer.buttonHandler(key.getKeyCode(), false))
  95                         abortBroadcast();
  96                 }
  97             }
  98         }
  99     }
 100
 101     private interface IMultiMediaReceiver
 102     {
 103         void register();
 104         void unregister();
 105     }
 106
 107     private static class NewApi
 108                     implements IMultiMediaReceiver, AudioManager.OnAudioFocusChangeListener
 109     {
 110         private AudioManager audio_manager;
 111         private ComponentName receiver_name;
 112         private boolean running = false;
 113
 114         NewApi(Context c)
 115         {
 116             audio_manager = (AudioManager)c.getSystemService(Context.AUDIO_SERVICE);
 117             receiver_name = new ComponentName(c, MediaReceiver.class);
 118         }
 119
 120         public void register()
 121         {
 122             try {
 123                 audio_manager.registerMediaButtonEventReceiver(receiver_name);
 124                 audio_manager.requestAudioFocus(this, AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN);
 125                 running = true;
 126             } catch (Exception e) {
 127                 // Nothing
 128                 e.printStackTrace();
 129             }
 130         }
 131
 132         public void unregister()
 133         {
 134             try
 135             {
 136                 audio_manager.unregisterMediaButtonEventReceiver(receiver_name);
 137                 audio_manager.abandonAudioFocus(this);
 138                 running = false;
 139             } catch (Exception e) {
 140                 // Nothing
 141                 e.printStackTrace();
 142             }
 143         }
 144
 145         public void onAudioFocusChange(int focusChange)
 146         {
 147             Logger.d("Audio focus" + ((focusChange>0)?"gained":"lost")+
 148                                          ": "+ focusChange);
 149             if (running)
 150             {   /* Play nice and stop for the the other app */
 151                 if (focusChange == AudioManager.AUDIOFOCUS_LOSS)
 152                     RockboxFramebuffer.buttonHandler(KeyEvent.KEYCODE_MEDIA_STOP, false);
 153             }
 154         }
 155
 156     }
 157
 158     private static class OldApi implements IMultiMediaReceiver
 159     {
 160         private static final IntentFilter filter = new IntentFilter(Intent.ACTION_MEDIA_BUTTON);
 161         private MediaReceiver receiver;
 162         private Context context;
 163         OldApi(Context c)
 164         {
 165             filter.setPriority(1); /* 1 higher than the built-in media player */
 166             receiver = new MediaReceiver();
 167             context = c;
 168         }
 169
 170         public void register()
 171         {
 172             context.registerReceiver(receiver, filter);
 173         }
 174
 175         public void unregister()
 176         {
 177             context.unregisterReceiver(receiver);
 178         }
 179
 180     }
 181 }