java - 无法解析方法ComputeDistanceBetween

Question

我正在使用 Google map 并支持 map fragment 类。我希望程序计算两点之间的距离。但是，我收到一条错误消息，指出我无法解析方法 ComputeDistanceBetween。我该如何解决？ (大部分代码取自Github)。

public class DistanceDemoActivity extends BaseDemoActivity implements GoogleMap.OnMarkerDragListener {
    private TextView mTextView;
    private Marker mMarkerA;
    private Marker mMarkerB;
    private Polyline mPolyline;
    private Object SphericalUtil;


    protected int getLayoutId() {
        return R.layout.distance_demo;
    }


    protected void startDemo() {
        mTextView = (TextView) findViewById(R.id.textView);

        getMap().moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(-33.8256, 151.2395), 10));
        getMap().setOnMarkerDragListener(this);

        mMarkerA = getMap().addMarker(new MarkerOptions().position(new LatLng(-33.9046, 151.155)).draggable(true));
        mMarkerB = getMap().addMarker(new MarkerOptions().position(new LatLng(-33.8291, 151.248)).draggable(true));
        mPolyline = getMap().addPolyline(new PolylineOptions().geodesic(true));

        Toast.makeText(this, "Drag the markers!", Toast.LENGTH_LONG).show();
        showDistance();
    }

   private void showDistance() {
        double distance = SphericalUtil.computeDistanceBetween(mMarkerA.getPosition(), mMarkerB.getPosition());
        mTextView.setText("The markers are " + formatNumber(distance) + " apart.");
    }

    private void updatePolyline() {
        mPolyline.setPoints(Arrays.asList(mMarkerA.getPosition(), mMarkerB.getPosition()));
    }

    private String formatNumber(double distance) {
        String unit = "m";
        if (distance < 1) {
            distance *= 1000;
            unit = "mm";
        } else if (distance > 1000) {
            distance /= 1000;
            unit = "km";
        }

        return String.format("%4.3f%s", distance, unit);
    }

    @Override
    public void onMarkerDragEnd(Marker marker) {
        showDistance();
        updatePolyline();
    }

    @Override
    public void onMarkerDragStart(Marker marker) {

    }

    @Override
    public void onMarkerDrag(Marker marker) {
        showDistance();
        updatePolyline();
    }
}

Answer 1

SphericalUtil 是 Google Maps API 实用程序库中的一个类，您正在声明一个名为 SphericalUtil 的对象。

删除此行:

private Object SphericalUtil;

此外，请确保您将 Google Maps API 实用程序库添加到 instructions 之后的 build.gradle 中。 .