使用线控耳机来操控应用功能

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使用线控耳机来操控应用功能

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实现原理：通过广播拦截来实现。

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（一）定义1个广播拦截器，用来拦截线控耳机按键产生的广播事件。

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import android.content.BroadcastReceiver;  import android.content.Context;  import android.content.Intent;  import android.os.Bundle;  import android.os.Handler;  import android.os.Message;  import android.util.Log;  import android.view.KeyEvent;    public class MediaButtonReceiver extends BroadcastReceiver {            /**      * Handler      */      private Handler handler;            /**      * 构造器.      * @param handler      */      public MediaButtonReceiver(Handler handler) {          this.handler = handler;      }        @Override      public void onReceive(Context context, Intent intent) {          boolean isActionMediaButton = Intent.ACTION_MEDIA_BUTTON.equals(intent.getAction());          if(!isActionMediaButton) return;          KeyEvent event = (KeyEvent)intent.getParcelableExtra(Intent.EXTRA_KEY_EVENT);          if(event==null) return;                    boolean isActionUp = (event.getAction()==KeyEvent.ACTION_UP);          if(!isActionUp) return;                    int keyCode = event.getKeyCode();          long eventTime = event.getEventTime()-event.getDownTime();//按键按下到松开的时长          Message msg = Message.obtain();          msg.what = 100;          Bundle data = new Bundle();          data.putInt("key_code", keyCode);          data.putLong("event_time", eventTime);          msg.setData(data);          handler.sendMessage(msg);                    //终止广播(不让别的程序收到此广播，免受干扰)          abortBroadcast();      }  }  

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（二）在主程序的处理：

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（1）定义并注册广播服务

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//初始化Handler对象  MyHandler handler = new MyHandler();  //初始化媒体(耳机)广播对象.  MediaButtonReceiver mediaButtonReceiver = new MediaButtonReceiver(handler);  //注册媒体(耳机)广播对象  IntentFilter intentFilter = new IntentFilter(Intent.ACTION_MEDIA_BUTTON);  intentFilter.setPriority(10000);  registerReceiver(mediaButtonReceiver, intentFilter);  

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也可以这样注册广播：

<receiver android:name="MediaButtonReceiver">    <intent-filter android:priority="10000">         <action android:name="android.intent.action.MEDIA_BUTTON" />    </intent-filter></receiver>

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private class MyHandler extends Handler{      @Override      public void handleMessage(Message msg) {          int what = msg.what;          switch(what){          case 100://单击按键广播              Bundle data = msg.getData();              //按键值              int keyCode = data.getInt("key_code");              //按键时长              long eventTime = data.getLong("event_time");              //设置超过2000毫秒，就触发长按事件              boolean isLongPress = (eventTime>2000);                            switch(keyCode){              case KeyEvent.KEYCODE_HEADSETHOOK://播放或暂停              case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE://播放或暂停                  playOrPause();                  break;                                //短按=播放下一首音乐，长按=当前音乐快进              case KeyEvent.KEYCODE_MEDIA_NEXT:                  if(isLongPress){                      fastNext(1);//自定义                  }else{                      playNext();//自定义                  }                  break;                                //短按=播放上一首音乐，长按=当前音乐快退                case KeyEvent.KEYCODE_MEDIA_PREVIOUS:                  if(isLongPress){                      fastPrevious(1);//自定义                  }else{                      playPrevious();//自定义                  }                  break;              }                            break;          default://其他消息-则扔回上层处理              super.handleMessage(msg);          }      }  }  

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（3）应用程序退出的时候，别忘了取消注册的广播拦截器。

unregisterReceiver(mediaButtonReceiver);  

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