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copied!<p>In the end I solved it by using a Proxy class. Here is the code!</p> <pre><code>private AudioManager theAudioManager; private Object myOnAudioFocusChangeListener = null; private static final int AUDIOMANAGER_AUDIOFOCUS_GAIN = 1; private static final int AUDIOMANAGER_AUDIOFOCUS_LOSS = -1; theAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); // instantiating the OnAudioFocusChangeListener by reflection (as it only exists from Android 2.2 onwards) // we use a Proxy class for implementing the listener public void setOnAudioFocusChangeListener() { Log.i(this, "setOnAudioFocusChangeListener()"); Class<?>[] innerClasses = theAudioManager.getClass().getDeclaredClasses(); for (Class<?> interfaze : innerClasses) { if (interfaze.getSimpleName().equalsIgnoreCase("OnAudioFocusChangeListener")) { Class<?>[] classArray = new Class<?>[1]; classArray[0] = interfaze; myOnAudioFocusChangeListener = Proxy.newProxyInstance(interfaze.getClassLoader(), classArray, new ProxyOnAudioFocusChangeListener()); } } } // called by onResume public void getAudioFocus() { if (myOnAudioFocusChangeListener != null) { Log.i(this, "getAudioFocus()"); try { Method[] methods = theAudioManager.getClass().getDeclaredMethods(); for (Method method : methods) { if (method.getName().equalsIgnoreCase("requestAudioFocus")) { method.invoke(theAudioManager, myOnAudioFocusChangeListener, AudioManager.STREAM_MUSIC, AUDIOMANAGER_AUDIOFOCUS_GAIN); Log.i(this, "requestAudioFocus"); } } } catch (Exception e) { Log.e(this, e.getMessage()); } } } // called by onPause public void releaseAudioFocus() { if (myOnAudioFocusChangeListener != null) { Log.i(this, "releaseAudioFocus()"); try { Method[] methods = theAudioManager.getClass().getDeclaredMethods(); for (Method method : methods) { if (method.getName().equalsIgnoreCase("abandonAudioFocus")) method.invoke(theAudioManager, myOnAudioFocusChangeListener); } } catch (Exception e) { Log.e(this, e.getMessage()); } } } </code></pre> <p><strong>PROXY OnAudioFocusChangeListener class</strong></p> <pre><code>private class ProxyOnAudioFocusChangeListener implements InvocationHandler { // implements the method onAudioFocusChange from the OnAudioFocusChangeListener public void onAudioFocusChange(int focusChange) { Log.e(this, "onAudioFocusChange() focusChange = " + focusChange); if (focusChange == AUDIOMANAGER_AUDIOFOCUS_LOSS) { Log.i(this, "AUDIOMANAGER_AUDIOFOCUS_LOSS"); Message msg = mHandler.obtainMessage(ControllerHandler.SET_ON_PAUSE); mHandler.sendMessage(msg); } else if (focusChange == AUDIOMANAGER_AUDIOFOCUS_GAIN) { Log.i(this, "AUDIOMANAGER_AUDIOFOCUS_GAIN"); // no action is taken } } // implements the method invoke from the InvocationHandler interface // it intercepts the calls to the listener methods // in this case it redirects the onAudioFocusChange listener method to the OnAudioFocusChange proxy method public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { Object result = null; try { if (args != null) { if (method.getName().equals("onAudioFocusChange") && args[0] instanceof Integer) { onAudioFocusChange((Integer) args[0]); } } } catch (Exception e) { throw new RuntimeException("unexpected invocation exception: " + e.getMessage()); } return result; } } </code></pre>

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