MapBox如何根据用户更改的位置动态地在片段textView中传递用户坐标

Question

我正在片段中使用mapbox地图。我设法放置了一些代码，以便在一个片段中打开地图并找到用户位置。我还编写了一个烤面包，显示用户的经度和纬度（这可能是另一个问题，因为烤面包仅显示纬度）。但是，当我尝试创建将自动更新的textView时，我的奋斗开始了，我的方法可以在下面的代码中看到。如果有人可以建议应如何更新代码或提出解决方法，将不胜感激。

    private View root;
    private MapView mapView;
    private TextView textView;
    private MapboxMap map;
    private PermissionsManager permissionsManager;
    private LocationEngine locationEngine;
    private LocationLayerPlugin locationLayerPlugin;
    private Location originLocation;


    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

    }

    @Nullable
    @Override
    public View onCreateView (LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

// Below I try to write something that will update my textView
        textView = (TextView) (root).findViewById(R.id.longitude_display_text);
        textView.setText("this is where I try to pass longitude of a user");

        root = inflater.inflate(R.layout.second_page, container, false);
        mapView =(MapView) (root).findViewById(R.id.mapView);
        mapView.onCreate(savedInstanceState);
        mapView.getMapAsync(this);
        return  root;
    }

    @Override
    public void onMapReady(MapboxMap mapboxMap) {
        map = mapboxMap;
        enableLocation();

        locationEngine.setPriority(LocationEnginePriority.HIGH_ACCURACY);
        locationEngine.setInterval(50000);
        locationEngine.activate();
        Location lastLocation = locationEngine.getLastLocation();

//Toast below only gives latitude , not sure if this because I should format number to give less digits,
//I tried formatting the number to give less digits but it did not work
        Toast.makeText(requireContext(), String.format(
                String.valueOf(locationEngine.getLastLocation().getLatitude()) , String.valueOf(locationEngine.getLastLocation().getLongitude())),
                Toast.LENGTH_LONG).show();
    }

Answer 1

String.format（）应该以格式文本作为第一个参数，后跟格式字符串中格式说明符引用的参数。试试这样的东西：

Toast.makeText(fragment.getContext(), String.format(fragment.getString(R.string.new_location),
                        String.valueOf(result.getLastLocation().getLatitude()),
                        String.valueOf(result.getLastLocation().getLongitude())),
                        Toast.LENGTH_SHORT).show();

在R.strings.xml中添加new_location字符串，如下所示：<string name="new_location">New latitude: %1$s New longitude: %2$s</string>

有关String.format（）的更多信息在这里：https://developer.android.com/reference/java/util/Formatter#format(java.lang.String,%20java.lang.Object...)

关于textview：在获得lastLocation之后，应在onCreateView（）中扩大布局并在onMapReady（）中更新textView之后声明它。onCreateView应该是：

@Nullable
    @Override
    public View onCreateView (LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
      root = inflater.inflate(R.layout.second_page, container, false);
        mapView =(MapView) (root).findViewById(R.id.mapView);
        mapView.onCreate(savedInstanceState);
        mapView.getMapAsync(this);
// Below I try to write something that will update my textView
            textView = (TextView) (root).findViewById(R.id.longitude_display_text);
            textView.setText("this is where I try to pass longitude of a user");
        return  root;
    }

和onMapReady（），在您的吐司之前，添加以下行

textView.setText(String.format(fragment.getString(R.string.new_location),
                        String.valueOf(result.getLastLocation().getLatitude()),
                        String.valueOf(result.getLastLocation().getLongitude()));