Android监听耳机插拔状态实现看视频插拔耳机暂停播放

最近接到一个需求，需求的内容是：看视频时拔出耳机，视频暂停播放；插入耳机，视频继续播放。

首先我们分析下这个需求，最重要是监听耳机的插拔状态。然后耳机又分为两种：有线耳机和蓝牙耳机，也就是我们要通过广播的方式监听这两种插拔状态，同时还要考虑着两种耳机同时连接时哪个优先收到音频声音呢？大家可以先想想。

动态注册广播监听

private var isRegisteredHeadsetReceiver = false

override fun onResume() {
  super.onResume()
  //注册广播
  if (!isRegisteredHeadsetReceiver) {
    try {
      val filter = IntentFilter()
      //监听有线耳机的两种方式
      filter.addAction(Intent.ACTION_HEADSET_PLUG)
      filter.addAction(AudioManager.ACTION_AUDIO_BECOMING_NOISY)
      //监听蓝牙耳机
      filter.addAction(BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED)
      registerReceiver(mReceiver, filter)
      isRegisteredHeadsetReceiver = true
    } catch (e: Exception) {
    }
  }
}

override fun onPause() {
  //注销广播
  if (isRegisteredHeadsetReceiver) {
    try {
      unregisterReceiver(mReceiver)
      isRegisteredHeadsetReceiver = false
    } catch (e: Exception) {
    }
  }
  super.onPause()
}

监听有线耳机的连接状态

方式一：监听系统广播Intent.ACTION_HEADSET_PLUG

通过这种方式，可以监听到耳机连接和断开的状态。

private var isHeadsetOn = false

private var mReceiver = object : BroadcastReceiver() {
       override fun onReceive(context: Context?, intent: Intent?) {
           val action = intent?.action
           if (TextUtils.equals(action, Intent.ACTION_HEADSET_PLUG)) {
               if (intent?.hasExtra("state") == true) {
                   if (intent.getIntExtra("state", 2) == 0) {
                       if (isHeadsetOn) {
                           Toast.makeText(mContext, "有线耳机拔出", Toast.LENGTH_SHORT).show()
                           isHeadsetOn = false
                           ...
                       }
                   } else if (intent.getIntExtra("state", 2) == 1) {
                       if (!isHeadsetOn) {
                           Toast.makeText(mContext, "有线耳机插入", Toast.LENGTH_SHORT).show()
                           isHeadsetOn = true
                           ...
                       }
                   }
               }
           }
       }
}

@Suppress("DEPRECATION")
private fun isWiredHeadsetOn(): Boolean {
   val am = getSystemService(Context.AUDIO_SERVICE) as AudioManager
   return am.isWiredHeadsetOn
}

override fun onCreate(savedInstanceState: Bundle?) {
   ...
   isHeadsetOn = isWiredHeadsetOn()
   ...
}

方式二：监听系统广播AudioManager.ACTION_AUDIO_BECOMING_NOISY

通过这种方式只能监听到有线和蓝牙耳机的断开的状态，不能监听其连接的状态。很显然满足不了我的需求。

private var mReceiver = object : BroadcastReceiver() {
        override fun onReceive(context: Context?, intent: Intent?) {
            val action = intent?.action
            if (TextUtils.equals(AudioManager.ACTION_AUDIO_BECOMING_NOISY)) {
                Toast.makeText(mContext, "有线耳机拔出", Toast.LENGTH_SHORT).show()
                ...
            }
        }
}

监听蓝牙耳机的连接状态

监听系统广播BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED，用于广播Headset配置文件的连接状态的更改。

//首先需要蓝牙的权限，否则无法接收到。
<uses-permission android:name="android.permission.BLUETOOTH"/>

private var mReceiver = object : BroadcastReceiver() {
        override fun onReceive(context: Context?, intent: Intent?) {
            val action = intent?.action
            if (TextUtils.equals(action, BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED)) {
                val state = intent?.getIntExtra(BluetoothProfile.EXTRA_STATE, -1)
                when (state) {
                    BluetoothProfile.STATE_CONNECTED -> {
                        Toast.makeText(mContext, "蓝牙耳机连接", Toast.LENGTH_SHORT).show()
                        ...
                    }
                    BluetoothProfile.STATE_DISCONNECTED -> {
                        Toast.makeText(mContext, "蓝牙耳机未连接", Toast.LENGTH_SHORT).show()
                        ...
                    }
                }
            }
        }
    }

最后，两种耳机同时连接时哪个优先收到音频声音呢？上面的代码一测试你就会发现，有线耳机优先于蓝牙耳机。