zoom out in MKMapView

When开发者_如何学Go you double tap on MKMapView : zoom in.

But how to zoom out??

There's always using two fingers to zoom in and out. On the emulator you need to hold down an option key to get 'two fingers' appear on the emulated screen (I think it's the Alt key but I use a PC keyboard on my mac so may differ on a real mac keyboard)

As for doing it procedurally you need to set the region on the mapkit. via the setRegion method of your MKMapKit object.

Make sure you're within bounds though as it will cause a crash if not. (i.e. long -180