private static final int MSG_SET_A2DP_SRC_CONNECTION_STATE = 101;
private static final int MSG_SET_A2DP_SINK_CONNECTION_STATE = 102;
setBluetoothA2dpDeviceConnectionState
onSetA2dpSinkConnectionState
makeA2dpDeviceUnavailableLater
makeA2dpDeviceUnavailableNow
makeA2dpDeviceAvailable