iPad Modal View Controllers

Modal view controllers are well documented in the View Controller Programming Guide for iPhone OS but here is a quick recap of how to present and dismiss a modal view. To keep things simple I will cover the steps for presenting the modal view when a button is pressed on a master view controller. When the button is pressed we need to create and show a detail view controller that contains a button that the user can use to dismiss the modal view controller. The NIB file for the detail view controller is trivial in this example consisting of just a single view containing a text label.

Allocating and showing the detail view controller is straightforward:

- (void)buttonAction:(id)sender {
// Create the modal view controller
DetailViewController *viewController = [[DetailViewController alloc]
initWithNibName:@”DetailViewController” bundle:nil];
// We are the delegate responsible for dismissing the modal view
viewController.delegate = self;
// Create a Navigation controller
UINavigationController *navController = [[UINavigationController alloc]
initWithRootViewController:viewController];
// show the navigation controller modally
[self presentModalViewController:navController animated:YES];
// Clean up resources
[navController release];
[viewController release];
}