get boundaries longitude and latitude from current zoom google maps

Question

i need to know long and lat of my four corners of current area as in this image

i have tried this but with no luck :

map.getBounds(); 

any help ?

Answer 1

You are half way there. All you need to do is to get the map bounds and then extract (and properly use) the coordinates of the corners.

var bounds = map.getBounds(); var ne = bounds.getNorthEast(); // LatLng of the north-east corner var sw = bounds.getSouthWest(); // LatLng of the south-west corder 

You get north-west and south-east corners from the two above:

var nw = new google.maps.LatLng(ne.lat(), sw.lng()); var se = new google.maps.LatLng(sw.lat(), ne.lng()); 

Just keep in mind that the map has to be already initialized, otherwise the map bounds are null or undefined.

If you want to be updated about every change of the viewport, use idle event listener:

google.maps.event.addListener(map, 'idle', function(ev){     // update the coordinates here }); 

Answer 2

In Android, you can find out corner LatLng (northeast, southwest) by this way, in the map, every time the camera listen(means gesture detect) they are called,

private var mapView: GoogleMap? = null 

............

    mapView?.setOnCameraMoveStartedListener { reasonCode ->         if (reasonCode == GoogleMap.OnCameraMoveStartedListener.REASON_GESTURE) {             val screenView: LatLngBounds =  mapView.getProjection().getVisibleRegion().latLngBounds             var northeast=screenView.northeast             var southwest=screenView.southwest             var center=screenView.center                                       Log.v("northeast LatLng","-:"+northeast)// LatLng of the north-east Screen             Log.v("southwest LatLng","-:"+southwest)// LatLng of the south-west Screen             Log.v("center LatLng","-:"+center)// LatLng of the center Screen         }     }