调用 requestLocationUpdates() 时不能使用 activity 作为 LocationListener 的实例

Question

在我的应用程序中，连接到 LocationServices.API 后，在 onConnected() 回调中，我启动了一个位置更新请求，问题是 Activity 处理进程（数据Activity) 不被识别为 LocationListener 的实例，它显示错误，并建议转换。

protected void startLocationUpdates() {
    PendingResult locationUpdatesResult = LocationServices.FusedLocationApi.requestLocationUpdates(locationGoogleApiClient, locationRequest, (com.google.android.gms.location.LocationListener) this);
}

当我将最后一个参数转换为 (com.google.android.gms.location.LocationListener) 时，IDE 让我编译，但是抛出了 ClassCastException

java.lang.ClassCastException: com.example.[...].DataActivity cannot be cast to com.google.android.gms.location.LocationListener

我真的不知道为什么会这样。

这是 Class 的声明。

public class DataActivity extends FragmentActivity implements LocationListener, ConnectionCallbacks , OnConnectionFailedListener, OnMapReadyCallback{

OnCreate():

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_data);

    //Create the GoogleLocationAPI reference
    buildGoogleLocationApiClient();

    //Create Location Request
    createLocationRequest();

    //Initialize the mapFragment
    initializeMapFragment();

    updateUI();
}

其他方法：

protected synchronized void buildGoogleLocationApiClient(){
    locationGoogleApiClient = new GoogleApiClient.Builder(this)
            .addApi(LocationServices.API)
            .addConnectionCallbacks(this)
            .addOnConnectionFailedListener(this)
            .build();
    locationGoogleApiClient.connect();
    Log.v("**INFO: ", "API CLIENT");
}

protected static void createLocationRequest() {
    locationRequest = new LocationRequest();
    locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    locationRequest.setInterval(10000);
    locationRequest.setFastestInterval(5000);
    Log.i("**INFO: ", "LocationRequest created");
}

protected void initializeMapFragment(){
    //Initialize the mapFragment
    mapFragment = (MapFragment) getFragmentManager().findFragmentById(R.id.map);
    //When mapFragment is ready...
    mapFragment.getMapAsync(this);
}

所以当建立连接（OnConnected）时，我调用这个方法，当错误弹出时。

protected void startLocationUpdates() {
    PendingResult locationUpdatesResult = LocationServices.FusedLocationApi.requestLocationUpdates(locationGoogleApiClient, locationRequest, this);
    locationUpdatesResult.await(); 
}

Answer 1

确保您的 DataActivity 实现了 com.google.android.gms.location.LocationListener 而不是 android.location.LocationListener。
您可能错误地导入了 android.location.LocationListener。

Answer 2

而不是public class DataActivity extends FragmentActivity implements LocationListener, ConnectionCallbacks , OnConnectionFailedListener, OnMapReadyCallback{

做

public class DataActivity extends FragmentActivity implements **com.google.android.gms.location.LocationListener**, ConnectionCallbacks , OnConnectionFailedListener, OnMapReadyCallback{

之后你必须实现它的所有方法

调用 requestLocationUpdates() 时不能使用 activity 作为 LocationListener 的实例

Can't use an activity as an instance of LocationListener when calling requestLocationUpdates()

android

localization

android-studio

location-services