How to create backBarButtomItem with custom view for a UINavigationController

Question

I have a UINavigationController into which I push several views. Inside viewDidLoad for one of these views I want to set the self.navigationI

Answer 1

This is how I create a custom square back button with an arrow instead of the usual text.

I simply setup a delegate for my UINavigationController. I use the app delegate for that because the window root view controller is the UINavigationController i want to control.

So AppDelegate.m (ARC):

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    ((UINavigationController*)_window.rootViewController).delegate = self;
    return YES;
}

#pragma mark - UINavigationControllerDelegate

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {
    if(navigationController.viewControllers.count > 1) {
        UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
        [button setImage:[UIImage imageNamed:@"back-arrow.png"] forState:UIControlStateNormal];
        [button setBackgroundColor:[UIColor grayColor]];
        button.frame = CGRectMake(0, 0, 44, 44);
        viewController.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:button];
        [button addEventHandler:^(id sender) {
            [navigationController popViewControllerAnimated:YES];
        } forControlEvents:UIControlEventTouchUpInside];
    }
}

I'm using BlocksKit to catch the button tap event. It's very convenient for stuff like this but you can also use the regular addTarget:action:forControlEvents: method