Android 10 如何解决蓝牙耳机听音乐过程，插入再拔出有线耳机，音乐不从蓝牙耳机发出

问题点：蓝牙耳机听音乐过程，插入再拔出有线耳机，音乐不从蓝牙耳机发出
代码路径：
packages/apps/Bluetooth/src/com/android/bluetooth/btservice/ActiveDeviceManager.java

a/src/com/android/bluetooth/btservice/ActiveDeviceManager.java
+++ b/src/com/android/bluetooth/btservice/ActiveDeviceManager.java
@@ -110,12 +110,13 @@ class ActiveDeviceManager {
     private static final int MESSAGE_HFP_ACTION_CONNECTION_STATE_CHANGED = 4;
     private static final int MESSAGE_HFP_ACTION_ACTIVE_DEVICE_CHANGED = 5;
     private static final int MESSAGE_HEARING_AID_ACTION_ACTIVE_DEVICE_CHANGED = 6;
-
+    private static final int MESSAGE_DELAY_ENTER_A2DP_ACTIVE_DEVICE= 7;
     private final AdapterService mAdapterService;
     private final ServiceFactory mFactory;
     private HandlerThread mHandlerThread = null;
     private Handler mHandler = null;
     private final AudioManager mAudioManager;
+    private int volume ;
     private final AudioManagerAudioDeviceCallback mAudioManagerAudioDeviceCallback;
 
     private final List mA2dpConnectedDevices = new LinkedList<>();
@@ -320,6 +321,13 @@ class ActiveDeviceManager {
                     }
                 }
                 break;
+                case MESSAGE_DELAY_ENTER_A2DP_ACTIVE_DEVICE: {
+                    Log.d(TAG, "MESSAGE_DELAY_ENTER_A2DP_ACTIVE_DEVICE ");
+                    setA2dpActiveDevice();
+                    mAudioManager.setStreamVolume(AudioManager.STREAM_MUSIC, volume, 0);
+                }
+                break;
+
             }
         }
     }
@@ -361,6 +369,21 @@ class ActiveDeviceManager {
 
         @Override
         public void onAudioDevicesRemoved(AudioDeviceInfo[] removedDevices) {
+            Log.d(TAG, "onAudioDevicesRemoved()  isWiredHeadsetOn " +mAudioManager.isWiredHeadsetOn());
+            if (mAudioManager.isWiredHeadsetOn()) {
+                return;
+            }
+
+            for (AudioDeviceInfo device : removedDevices) {
+                Log.d(TAG, "onAudioDevicesRemoved: removedDevices: " + device.getType()+"  isWiredAudioHeadset  "+ isWiredAudioHeadset(devi
ce));
+                if (isWiredAudioHeadset(device)) {
+                    volume = mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
+                    mAudioManager.setStreamVolume(AudioManager.STREAM_MUSIC, 0, 0);
+                    mHandler.removeMessages(MESSAGE_DELAY_ENTER_A2DP_ACTIVE_DEVICE);
+                    mHandler.sendEmptyMessageDelayed(MESSAGE_DELAY_ENTER_A2DP_ACTIVE_DEVICE,1000);
+                    break;
+                }
+            }
         }
     }
 
@@ -368,6 +391,7 @@ class ActiveDeviceManager {
         mAdapterService = service;
         mFactory = factory;
         mAudioManager = (AudioManager) service.getSystemService(Context.AUDIO_SERVICE);
+        volume = mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
         mAudioManagerAudioDeviceCallback = new AudioManagerAudioDeviceCallback();
     }
 
@@ -433,6 +457,15 @@ class ActiveDeviceManager {
         }
         mA2dpActiveDevice = device;
     }
+       
+    private void setA2dpActiveDevice() {
+        Log.d(TAG, "setA2dpActiveDevice()");
+        if (mA2dpActiveDevice == null && !mA2dpConnectedDevices.isEmpty()) {
+           int prevActiveDeviceIndex = mA2dpConnectedDevices.size() - 1;
+           BluetoothDevice prevActiveDevice = mA2dpConnectedDevices.get(prevActiveDeviceIndex);
+           setA2dpActiveDevice(prevActiveDevice);
+        }
+    }
 
     private void setHfpActiveDevice(BluetoothDevice device) {