需求：用户插入耳机后，APP提示用户耳机已插入，可选择耳机播放或外放模式。用户选择耳机播放，什么都不用做；用户选择外放模式，向系统发送模拟拔出耳机事件
（耳机实际未拔出），声音外放。
实现：BroadcastReceiver监听耳机插入/拔出事件，在插入时进行处理，通过反射向系统发送模拟拔出事件。

  private String headsetName;
  private int microphone;

  @Override
  public void onReceive(final Context context, Intent intent) {

      if (intent.getAction().equals(Intent.ACTION_HEADSET_PLUG)) {
          int state = intent.getIntExtra("state", -1);
          headsetName = intent.getStringExtra("name");
          microphone = intent.getIntExtra("microphone", 0);

          switch (state) {
              case 0:
                  // 拔出耳机
                  break;
              case 1:
                  // 插入耳机，进行事件处理...
                  ...
                  sendIntent();// 模拟发送事件
                  break;
          }
      }
  }

  private void sendIntent() {
      Intent intent = new Intent(Intent.ACTION_HEADSET_PLUG);
      intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);
      intent.putExtra("state", 0);
      intent.putExtra("name", headsetName);
      intent.putExtra("microphone", microphone);

      Method m;
      AudioManager am = ((AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE));
      try {
          if (Build.VERSION.SDK_INT < 16) {
              Class<?> clazz = Class.forName("android.app.ActivityManagerNative");
              m = clazz.getMethod("broadcastStickyIntent", Intent.class, String.class);
              m.setAccessible(true);
              m.invoke(clazz, intent, null);
              return;
          }
          m = am.getClass().getMethod("setWiredDeviceConnectionState", Integer.TYPE, Integer.TYPE, String.class);
          m.setAccessible(true);
          Object[] objArr = new Object[3];
          objArr[0] = (intent.getIntExtra("microphone", 0) == 0) ? 8 : 4;
          objArr[1] = intent.getIntExtra("state", 0);
          objArr[2] = intent.getStringExtra("name");
          m.invoke(am, objArr);
      } catch (ClassNotFoundException | NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
          e.printStackTrace();
      }
  }