Question

我在这个应用程序中开发一个Android应用程序，我想在地图上绘制路径

当用户移动路径自动绘制时，我发现lat和long以及每次更改

当位置发生变化时，我希望在每次更改位置时在地图上绘制线条

我试过这个

public void onLocationChanged(Location location) {

    String msg = "Location:" + location.getLatitude() + ","
            + location.getLongitude();
    Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
    double new_lat = location.getLatitude();
    double new_long = location.getLongitude();
    drawTrack(new_lat, new_long, previous_lat, previous_long);
    previous_lat = new_lat;
    previous_long = new_long;
}

Answer 1

这就是我所做的：

public void onLocationChanged(Location location) {
    prevLatitude = latitude;
    prevLongitude = longitude;
    latitude = location.getLatitude();
    longitude = location.getLongitude();
    latLng = new LatLng(latitude, longitude);

    PolylineOptions pOptions = new PolylineOptions()
        .width(5)
        .color(Color.GREEN)
        .geodesic(true);
    for (int z = 0; z < routePoints.size(); z++) {
        LatLng point = routePoints.get(z);
        pOptions.add(point);
    }
    line = googleMap.addPolyline(pOptions);
    routePoints.add(latLng);
}

其中routePoints是LatLng的arraylist，line是你的折线，googleMap当然是你的GoogleMap。所以在课程开头添加：

private GoogleMap googleMap;
private Polyline line;
private ArrayList<LatLng> routePoints;

并在onCreate中添加：

routePoints = new ArrayList<LatLng>();

希望这对你有所帮助！:)

如何在用户自动移动绘制线时在Google地图上绘制线条

1 个答案: