问题:

I want to use Scale controls in the google map for iOS,but I found nothing in the document of google map SDK for iOS about scale controls.Is there a Scale Controls in google map SDK for iOS ?

回答1:

You need to use zoom levels in GMSCameraPosition by providing lang, lat values.

GMSCameraPosition Class Reference

(float) zoom [read, assign] Zoom level. Zoom uses an exponentional scale, where zoom 0 represents the entire world as a 256 x 256 square. Each successive zoom level increases magnification by a factor of 2. At zoom 10, the entire world is a 256k x 256k square, and so on.

For the controls you need to use your custom controls -,+ and for zoom in and out. Use any of the Static Public Member Functions for adjusting the zoom levels on the GMSCameraPosition.
Then [mapView_ setCamera:myCamera];

zoom level of the camera, read this

Hope that helps!!

回答2:

float actualZoom;
#define SENSITY_OF_ZOOM 0.5

set your actualZoom after you alloc init your map:

actualZoom = _mapView.camera.zoom;

the method:

 - (void) mapView:(GMSMapView *)mapView didChangeCameraPosition:(GMSCameraPosition *)position{
        if (fabsf(_mapView.camera.zoom - actualZoom) > SENSITY_OF_ZOOM) {
            NSLog(@"user zoomed enough");
            if (_mapView.camera.zoom > actualZoom) {
               actualZoom = actualZoom + SENSITY_OF_ZOOM;
            }
            else{
                actualZoom = actualZoom - SENSITY_OF_ZOOM;
            }
        }
    }