how to disable a navigation bar button item in iOS

Question

I have created a navigation controller. In the second view (which is pushed), I have some webservice call and placing a overlay view and setting

self.view.use

Answer 1

Just disable your UINavigationController view and navigation bar interaction:

self.navigationController.navigationBar.userInteractionEnabled = NO;
self.navigationController.view.userInteractionEnabled = NO;

And enable it when you need it back:

self.navigationController.navigationBar.userInteractionEnabled = YES;
self.navigationController.view.userInteractionEnabled = YES;