如何在地图上的特定位置添加标记?
我看到了这段显示触摸位置坐标的代码。我希望每次触摸标记时都将其弹出或显示在同一位置。我该怎么做?
public boolean onTouchEvent(MotionEvent event, MapView mapView) {
if (event.getAction() == 1) {
GeoPoint p = mapView.getProjection().fromPixels(
(int) event.getX(),
(int) event.getY());
Toast.makeText(getBaseContext(),
p.getLatitudeE6() / 1E6 + "," +
p.getLongitudeE6() /1E6 ,
Toast.LENGTH_SHORT).show();
mapView.invalidate();
}
return false;
}
您要添加OverlayItem。 Google Mapview tutorial显示如何使用它。
如果要在触摸的位置添加标记,则应执行以下操作:
public boolean onTouchEvent(MotionEvent event, MapView mapView) {
if (event.getAction() == 1) {
GeoPoint p = mapView.getProjection().fromPixels(
(int) event.getX(),
(int) event.getY());
Toast.makeText(getBaseContext(),
p.getLatitudeE6() / 1E6 + "," +
p.getLongitudeE6() /1E6 ,
Toast.LENGTH_SHORT).show();
mapView.getOverlays().add(new MarkerOverlay(p));
mapView.invalidate();
}
return false;
}
出现此消息后,请检查我是否正在调用MarkerOverlay。为了使它起作用,您必须创建另一个Overlay MapOverlay:
class MarkerOverlay extends Overlay{
private GeoPoint p;
public MarkerOverlay(GeoPoint p){
this.p = p;
}
@Override
public boolean draw(Canvas canvas, MapView mapView,
boolean shadow, long when){
super.draw(canvas, mapView, shadow);
//---translate the GeoPoint to screen pixels---
Point screenPts = new Point();
mapView.getProjection().toPixels(p, screenPts);
//---add the marker---
Bitmap bmp = BitmapFactory.decodeResource(getResources(), /*marker image*/);
canvas.drawBitmap(bmp, screenPts.x, screenPts.y-50, null);
return true;
}
}
希望您觉得这有用!