Android：OnTouchListener在MapView上没有响应

Question

I have the following code to show my actual location on Google Maps:

public class LocationProjectActivity extends MapActivity implements OnTouchListener {
private MapController mapController;
private MapView mapView;
private LocationManager locationManager;
private MyOverlays itemizedoverlay;
private MyLocationOverlay myLocationOverlay;
private GeoPoint MyPoint;
public static int longitude;
public static int latitude;
private GeoPoint destinationPoint;

public void onCreate(Bundle bundle) {
  super.onCreate(bundle);
  setContentView(R.layout.main);
  mapView = (MapView) findViewById(R.id.mapview);
  mapView.setBuiltInZoomControls(true);
  mapView.setSatellite(true);
  mapView.computeScroll();
  mapController = mapView.getController();
  mapController.setZoom(13);
  locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
  locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, new GeoUpdateHandler());
  myLocationOverlay = new MyLocationOverlay(this, mapView);
  mapView.getOverlays().add(myLocationOverlay);
  myLocationOverlay.runOnFirstFix(new Runnable() {
    public void run() {
      mapView.getController().animateTo(myLocationOverlay.getMyLocation());
    }
  });
}

@Override
public boolean onTouch(View v, MotionEvent event) {
  System.out.println("SCREEN WAS CLICKED");
  return true;
}

What I want to do is catch when I touch the screen, but the method is never called. I already searched and found this: OnTouch in map

I tried everything and the only code that works was this:

mapView.setOnTouchListener(new OnTouchListener() {
  public boolean onTouch(View v, MotionEvent event) {
    // Your code and remember to return true!        
    return (true);
  }
});

The problem is that if I use this code, my MapView loses the natural fling and zoom that it already has, so how can I have everything in my MapView?

Thank you.

Answer 1

There are two ways you can achieve what you are looking for and below is the code:

@Override 
      public boolean onTap(GeoPoint p, MapView mapView) {
            Log.d("tap event ", "tap called");
            mapOverlays = mapView.getOverlays();
            drawable  =getResources().getDrawable(R.drawable.marker);
            itemizedOverlay = new SitesOverlay(drawable);
            int lat=(int)p.getLatitudeE6();
            int lng=(int)p.getLongitudeE6();


            GeoPoint point = new GeoPoint(lat,lng);
            Log.d("tap event ", "tapcalled"+lat+""+lng);
            OverlayItem overlayitem = new OverlayItem(point, "", "");

            items.add(overlayitem);
            populate();
            Log.d("tap event ", "populated");
            //      mapOverlays.add(itemizedOverlay);   


            return true;
        }

and you can do this in this way but this doesn't add any overlay item/pin/marker on the map.

@Override
public boolean onTouchEvent(MotionEvent event, MapView mapView) 
{   
    //---when user lifts his finger---
    if (event.getAction() == 1) {                
        p = mapView.getProjection().fromPixels(
            (int) event.getX(),
            (int) event.getY());
            Toast.makeText(getBaseContext(), 
                p.getLatitudeE6() / 1E6 + "," + 
                p.getLongitudeE6() /1E6 , 
                Toast.LENGTH_SHORT).show();
    }                            
    return false;
}    

Here is the link to the tutorial to detect touch any where on the Map

Detect touch on MapView

To make marker/pin/item overlay over the map and detect on click of each pin/marker

Detect touch on marker in MapView

I hope this will help you :)

Thanks.

Answer 2

If you just want to see when you touch the screen, you can still return false which will allow all the other drag and zoom touch events to work.

You would only return true if you want a separate touch event to NOT continue to the others.