iPhone UINavigationController problems (invisible Button, title)

Question

I have two problems with the UINavigationController.

Problem 1

On the initial view I programmatically added a rightBarButtonItem.

When I push the navigationView to the right, everything works right and it appears a back button with the title of the previous view.

When I click the back button, I get back. But then this button is gone. But it's not really gone, it's just invisible, because it can still be clicked.

Problem 2

When I push the viewController on the right, I can't set the title. I tried it before pushing the view with

myViewController.title = @"someTitle";

and I tried it also inside of the viewController with

self.title = @"someTitle";

but nothing works here.

Answer 1

I found the problem:

I was adding a custom background image to the navigationBar. Somehow this image got over the title / button.

So if you ever want to implement a custom background image, don't user this:

UIImageView *backgroundImage = [[UIImageView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 44.0)];
[backgroundImage setImage:[UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"headerBg" ofType:@"png"]]];
[navigationController.navigationBar insertSubview:backgroundImage atIndex:0];
[backgroundImage release];

But instead, use this:

@implementation UINavigationBar (CustomImage)
- (void)drawRect:(CGRect)rect {
    UIImage *image = [UIImage imageNamed: @"headerBg.png"];
    [image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}
@end

Answer 2

Problem 1: Sounds odd. Don't really have an answer for that :-/

Problem 2: Can you provide some more code snippets on this, like the whole method bodies where you tried to set the title?