Java tutorial
/* * Copyright (C) 2007 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. */ // Modified for Lyrics Match by Karim Abou Zeid (kabouzeid). package com.dragedy.playermusic.service; import android.annotation.SuppressLint; import android.content.Context; import android.content.Intent; import android.os.Handler; import android.os.Message; import android.os.PowerManager; import android.os.PowerManager.WakeLock; import android.support.v4.content.WakefulBroadcastReceiver; import android.util.Log; import android.view.KeyEvent; import com.dragedy.playermusic.BuildConfig; /** * Used to control headset playback. * Single press: pause/resume * Double press: next track * Triple press: previous track */ public class MediaButtonIntentReceiver extends WakefulBroadcastReceiver { private static final boolean DEBUG = BuildConfig.DEBUG; public static final String TAG = MediaButtonIntentReceiver.class.getSimpleName(); private static final int MSG_HEADSET_DOUBLE_CLICK_TIMEOUT = 2; private static final int DOUBLE_CLICK = 400; private static WakeLock mWakeLock = null; private static int mClickCounter = 0; private static long mLastClickTime = 0; @SuppressLint("HandlerLeak") // false alarm, handler is already static private static Handler mHandler = new Handler() { @Override public void handleMessage(final Message msg) { switch (msg.what) { case MSG_HEADSET_DOUBLE_CLICK_TIMEOUT: final int clickCount = msg.arg1; final String command; if (DEBUG) Log.v(TAG, "Handling headset click, count = " + clickCount); switch (clickCount) { case 1: command = MusicService.ACTION_TOGGLE_PAUSE; break; case 2: command = MusicService.ACTION_SKIP; break; case 3: command = MusicService.ACTION_REWIND; break; default: command = null; break; } if (command != null) { final Context context = (Context) msg.obj; startService(context, command); } break; } releaseWakeLockIfHandlerIdle(); } }; @Override public void onReceive(final Context context, final Intent intent) { if (DEBUG) Log.v(TAG, "Received intent: " + intent); if (handleIntent(context, intent) && isOrderedBroadcast()) { abortBroadcast(); } } public static boolean handleIntent(final Context context, final Intent intent) { final String intentAction = intent.getAction(); if (Intent.ACTION_MEDIA_BUTTON.equals(intentAction)) { final KeyEvent event = intent.getParcelableExtra(Intent.EXTRA_KEY_EVENT); if (event == null) { return false; } final int keycode = event.getKeyCode(); final int action = event.getAction(); final long eventTime = event.getEventTime(); String command = null; switch (keycode) { case KeyEvent.KEYCODE_MEDIA_STOP: command = MusicService.ACTION_STOP; break; case KeyEvent.KEYCODE_HEADSETHOOK: case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE: command = MusicService.ACTION_TOGGLE_PAUSE; break; case KeyEvent.KEYCODE_MEDIA_NEXT: command = MusicService.ACTION_SKIP; break; case KeyEvent.KEYCODE_MEDIA_PREVIOUS: command = MusicService.ACTION_REWIND; break; case KeyEvent.KEYCODE_MEDIA_PAUSE: command = MusicService.ACTION_PAUSE; break; case KeyEvent.KEYCODE_MEDIA_PLAY: command = MusicService.ACTION_PLAY; break; } if (command != null) { if (action == KeyEvent.ACTION_DOWN) { if (event.getRepeatCount() == 0) { // Only consider the first event in a sequence, not the repeat events, // so that we don't trigger in cases where the first event went to // a different app (e.g. when the user ends a phone call by // long pressing the headset button) // The service may or may not be running, but we need to send it // a command. if (keycode == KeyEvent.KEYCODE_HEADSETHOOK) { if (eventTime - mLastClickTime >= DOUBLE_CLICK) { mClickCounter = 0; } mClickCounter++; if (DEBUG) Log.v(TAG, "Got headset click, count = " + mClickCounter); mHandler.removeMessages(MSG_HEADSET_DOUBLE_CLICK_TIMEOUT); Message msg = mHandler.obtainMessage(MSG_HEADSET_DOUBLE_CLICK_TIMEOUT, mClickCounter, 0, context); long delay = mClickCounter < 3 ? DOUBLE_CLICK : 0; if (mClickCounter >= 3) { mClickCounter = 0; } mLastClickTime = eventTime; acquireWakeLockAndSendMessage(context, msg, delay); } else { startService(context, command); } return true; } } } } return false; } private static void startService(Context context, String command) { final Intent intent = new Intent(context, MusicService.class); intent.setAction(command); startWakefulService(context, intent); } private static void acquireWakeLockAndSendMessage(Context context, Message msg, long delay) { if (mWakeLock == null) { Context appContext = context.getApplicationContext(); PowerManager pm = (PowerManager) appContext.getSystemService(Context.POWER_SERVICE); mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "Phonograph headset button"); mWakeLock.setReferenceCounted(false); } if (DEBUG) Log.v(TAG, "Acquiring wake lock and sending " + msg.what); // Make sure we don't indefinitely hold the wake lock under any circumstances mWakeLock.acquire(10000); mHandler.sendMessageDelayed(msg, delay); } private static void releaseWakeLockIfHandlerIdle() { if (mHandler.hasMessages(MSG_HEADSET_DOUBLE_CLICK_TIMEOUT)) { if (DEBUG) Log.v(TAG, "Handler still has messages pending, not releasing wake lock"); return; } if (mWakeLock != null) { if (DEBUG) Log.v(TAG, "Releasing wake lock"); mWakeLock.release(); mWakeLock = null; } } }