OutgoingCall的ConnectionService实现

我正在尝试实现ConnectionService，PhoneAccount和PhoneAccountHandle，以获取断开我拨出呼叫的原因（例如，用户拒绝了呼叫，无法接通等）。到目前为止，我已经能够使用customPhoneAccount发起呼叫，但是该电话从未经过，因此我无法得到答复。

这是我现在编写的代码：
register（）是从我的活动中调用以注册phoneAccount的方法：

public void register() {
    TelecomManager manager = (TelecomManager) getSystemService(TELECOM_SERVICE);
    PhoneAccountHandle phOneAccountHandle= new PhoneAccountHandle(
            new ComponentName(getPackageName(),
                    MyConnectionService.class.getName()), "myConnectionServiceId");
    PhoneAccount.Builder builder = PhoneAccount.builder(phoneAccountHandle, "CustomAccount");
    builder.setCapabilities(PhoneAccount.CAPABILITY_CALL_PROVIDER | PhoneAccount.CAPABILITY_CONNECTION_MANAGER);
    PhoneAccount phOneAccount= builder.build();
    manager.registerPhoneAccount(phoneAccount);
}

发起呼叫的call（）方法：

 public void call() {
    TelecomManager manager = (TelecomManager) getSystemService(TELECOM_SERVICE);
    PhoneAccountHandle phOneAccountHandle= new PhoneAccountHandle(
            new ComponentName(getPackageName(),
                    MyConnectionService.class.getName()), "myConnectionServiceId");
    Bundle test = new Bundle();
    test.putParcelable(TelecomManager.EXTRA_PHONE_ACCOUNT_HANDLE, phoneAccountHandle);
    manager.placeCall(Uri.parse("tel:" + "1212312312"), test);
}

这是MyConnectionService：

public class MyConnectionService extends ConnectionService {

public static final String TAG = MyConnectionService.class.getName();
@Override
public int onStartCommand(Intent intent,int flags, int startId) {
    Log.d(TAG, "On Start");
    return super.onStartCommand(intent, flags, startId);
}

@Override
public Connection onCreateOutgoingConnection(PhoneAccountHandle connectionManagerPhoneAccount, ConnectionRequest request) {
    Connection cOnnection= super.onCreateOutgoingConnection(connectionManagerPhoneAccount, request);
    Log.d(TAG, connection.getDisconnectCause().getReason());
    return connection;
}

@Override
public void onCreateOutgoingConnectionFailed(PhoneAccountHandle connectionManagerPhoneAccount, ConnectionRequest request) {
    if (request != null) {
        Log.d(TAG, request.toString());
    }
    super.onCreateOutgoingConnectionFailed(connectionManagerPhoneAccount, request);
}

我尝试了不同的功能以及与ConnectionService相关的其他线程上提到的所有选项，但无法获得所需的结果，有人可以在这方面帮助我吗？