Get the the coordinates (Latitude and Longitude) currently displayed on MapView

Here is a example to get the coordinates (Latitude and Longitude) currently displayed on MapView.



To get the coordinate of a point corspondint to a pixel on screen, we can use the method MapView.getProjection().fromPixels(x, y).

package com.exercise.AndroidMap;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapView;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class AndroidMapActivity extends MapActivity {
 
 MapView myMap;
 
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
       myMap = (MapView) findViewById(R.id.map);
       myMap.setBuiltInZoomControls(true);
      
       Button buttonGetInfo = (Button)findViewById(R.id.getinfo);
       buttonGetInfo.setOnClickListener(buttonGetInfoOnClickListener);
   }

 @Override
 protected boolean isRouteDisplayed() {
  // TODO Auto-generated method stub
  return false;
 }
 
 Button.OnClickListener buttonGetInfoOnClickListener
 = new Button.OnClickListener(){

  @Override
  public void onClick(View v) {
   // TODO Auto-generated method stub
   
   GeoPoint mapCenter = myMap.getMapCenter();
   
   float centerLatitude = (float)(mapCenter.getLatitudeE6())/1000000;
   float centerLongitude = (float)(mapCenter.getLongitudeE6())/1000000;
   
   float latitudeSpan = (float)(myMap.getLatitudeSpan())/1000000;
   float longitudeSpan = (float)(myMap.getLongitudeSpan()/1000000);
   
   GeoPoint mapTopLeft = myMap.getProjection().fromPixels(0, 0);
   float topLatitude = (float)(mapTopLeft.getLatitudeE6())/1000000;
   float leftLongitude = (float)(mapTopLeft.getLongitudeE6())/1000000;
   
   GeoPoint mapBottomRight
   = myMap.getProjection().fromPixels(myMap.getWidth(), myMap.getHeight());
   float bottomLatitude = (float)(mapBottomRight.getLatitudeE6())/1000000;
   float rightLongitude = (float)(mapBottomRight.getLongitudeE6())/1000000;

   int zoomLevel = myMap.getZoomLevel();
   
   String info =
     "Center: " + centerLatitude + "/" + centerLongitude + "\n"
     + "Top Left: " + topLatitude + "/" + leftLongitude + "\n"
     + "Bottom Right: " + bottomLatitude + "/" + rightLongitude + "\n"
     + "latitudeSpan: " + latitudeSpan + "\n"
     + "longitudeSpan: " + longitudeSpan + "\n"
     + "zoomLevel: " + zoomLevel;
   
   Toast.makeText(AndroidMapActivity.this,
     info,
     Toast.LENGTH_LONG).show();
  }};
}

Related Article:
- A minimal Map application using MapActivity

next:
- Draw on a custom View over MapView