(L1) AudioService AudioServiceBroadcastReceiver

startBluetoothSco

stopBluetoothSco

startBluetoothScoVirtualCall

---> startBluetoothScoInt --> ScoClient incCount ---> requestScoState ----> call BluetoothHeadset APIs

setBluetoothScoOn

----> setForceUse

setMode

 -----> provide for telephony

构造函数中注册intent

// Register for device connection intent broadcasts.
IntentFilter intentFilter =
new IntentFilter(BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED);
intentFilter.addAction(BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED);
intentFilter.addAction(Intent.ACTION_DOCK_EVENT);
intentFilter.addAction(AudioManager.ACTION_USB_AUDIO_ACCESSORY_PLUG);
intentFilter.addAction(AudioManager.ACTION_USB_AUDIO_DEVICE_PLUG);
intentFilter.addAction(Intent.ACTION_SCREEN_ON);
intentFilter.addAction(Intent.ACTION_SCREEN_OFF);
intentFilter.addAction(Intent.ACTION_USER_SWITCHED);
intentFilter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);

intentFilter.addAction(Intent.ACTION_CONFIGURATION_CHANGED);

context.registerReceiver(mReceiver, intentFilter);

AudioServiceBroadcastReceiver

Intent.ACTION_DOCK_EVENT

BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED

Sco 连接 或 断开 的处理

state = intent.getIntExtra(BluetoothProfile.EXTRA_STATE,
BluetoothProfile.STATE_DISCONNECTED);
outDevice = AudioSystem.DEVICE_OUT_BLUETOOTH_SCO;
inDevice = AudioSystem.DEVICE_IN_BLUETOOTH_SCO_HEADSET;
String address = null;

BluetoothDevice btDevice = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
if (btDevice == null) {
return;
}

address = btDevice.getAddress();
BluetoothClass btClass = btDevice.getBluetoothClass();
// 区分 out device,最终分为两种 sco headset, sco carkit
if (btClass != null) {
switch (btClass.getDeviceClass()) {
case BluetoothClass.Device.AUDIO_VIDEO_WEARABLE_HEADSET:
case BluetoothClass.Device.AUDIO_VIDEO_HANDSFREE:
outDevice = AudioSystem.DEVICE_OUT_BLUETOOTH_SCO_HEADSET;
break;
case BluetoothClass.Device.AUDIO_VIDEO_CAR_AUDIO:
outDevice = AudioSystem.DEVICE_OUT_BLUETOOTH_SCO_CARKIT;
break;
}
}

if (!BluetoothAdapter.checkBluetoothAddress(address)) {
address = "";
}
// 判断连接状态:连接 或者 断开
boolean connected = (state == BluetoothProfile.STATE_CONNECTED);
// out device, in device 由 handleDeviceConnection 分别处理
boolean success = handleDeviceConnection(connected, outDevice, address) &&
handleDeviceConnection(connected, inDevice, address);
if (success) {
synchronized (mScoClients) {
if (connected) {
mBluetoothHeadsetDevice = btDevice;
} else {
mBluetoothHeadsetDevice = null;
resetBluetoothSco();
}
}
}

AudioManager.ACTION_USB_AUDIO_ACCESSORY_PLUG

AudioManager.ACTION_USB_AUDIO_DEVICE_PLUG

BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED

sco 状态改变 则改变变量 mScoAudioState, 在requestScoState, checkScoAudioState, disconnectBluetoothSco 时会用到

boolean broadcast = false;
int scoAudioState = AudioManager.SCO_AUDIO_STATE_ERROR;
synchronized (mScoClients) {
int btState = intent.getIntExtra(BluetoothProfile.EXTRA_STATE, -1);
// broadcast intent if the connection was initated by AudioService
if (!mScoClients.isEmpty() &&
(mScoAudioState == SCO_STATE_ACTIVE_INTERNAL ||
mScoAudioState == SCO_STATE_ACTIVATE_REQ ||
mScoAudioState == SCO_STATE_DEACTIVATE_REQ)) {
//   broadcast 只有这种情况下是 true
broadcast = true;
}
switch (btState) {
case BluetoothHeadset.STATE_AUDIO_CONNECTED:
scoAudioState = AudioManager.SCO_AUDIO_STATE_CONNECTED;
if (mScoAudioState != SCO_STATE_ACTIVE_INTERNAL &&
mScoAudioState != SCO_STATE_DEACTIVATE_REQ &&
mScoAudioState != SCO_STATE_DEACTIVATE_EXT_REQ) {
mScoAudioState = SCO_STATE_ACTIVE_EXTERNAL;
}
break;
case BluetoothHeadset.STATE_AUDIO_DISCONNECTED:
scoAudioState = AudioManager.SCO_AUDIO_STATE_DISCONNECTED;
mScoAudioState = SCO_STATE_INACTIVE;
clearAllScoClients(0, false);
break;
case BluetoothHeadset.STATE_AUDIO_CONNECTING:
if (mScoAudioState != SCO_STATE_ACTIVE_INTERNAL &&
mScoAudioState != SCO_STATE_DEACTIVATE_REQ &&
mScoAudioState != SCO_STATE_DEACTIVATE_EXT_REQ) {
mScoAudioState = SCO_STATE_ACTIVE_EXTERNAL;
}
default:
// do not broadcast CONNECTING or invalid state
broadcast = false;
break;
}
}

if (broadcast) {
broadcastScoConnectionState(scoAudioState);
//FIXME: this is to maintain compatibility with deprecated intent
// AudioManager.ACTION_SCO_AUDIO_STATE_CHANGED. Remove when appropriate.
Intent newIntent = new Intent(AudioManager.ACTION_SCO_AUDIO_STATE_CHANGED);
newIntent.putExtra(AudioManager.EXTRA_SCO_AUDIO_STATE, scoAudioState);
sendStickyBroadcastToAll(newIntent);
}

checkScoAudioState

判断条件中, m

if (mBluetoothHeadset != null && mBluetoothHeadsetDevice != null &&
mScoAudioState == SCO_STATE_INACTIVE &&
mBluetoothHeadset.getAudioState(mBluetoothHeadsetDevice)
!= BluetoothHeadset.STATE_AUDIO_DISCONNECTED) {
mScoAudioState = SCO_STATE_ACTIVE_EXTERNAL;
}

requestScoState

disconnectBluetoothSco

Intent.ACTION_SCREEN_ON

Intent.ACTION_SCREEN_OFF

Intent.ACTION_CONFIGURATION_CHANGED

Intent.ACTION_USER_SWITCHED