Adding an UIView over a MKMapView

问题:

I am trying to put a button in the corner of my MKMapView to control whether the map stays locked on to the user's location. What I have in mind is to create a UIView with a button on and add it over my MKMapView (not as an annotation or something) I can't figure this out with Interface Builder.

How can I add this button programmatically?

Controlling whether it actually follows the user etc. is already sorted - just need the button for it.

回答1:

It looks like you are directly setting the controller's view outlet to an MKMapView object rather than a UIView object containing the MKMapView object. You cannot drop the button in such case on top of the MKMapView object in the IB. There are two ways you can deal with this,

1. Declare an outlet for the button and drop the button in the IB. This needn't be on top of the MKMapView object. Set the outlet to, say, a button property. Then in viewDidLoad do [self.view addSubview:self.button]; after setting the button's frame. (or)
2. Drop a new UIView object in IB and put the MKMapView object inside it. Set the controller's view to this container UIView object. Later drop the button on top of the MKMapView object and set it to its appropriate location.