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iosobjective-cuinavigationbaruinavigationitem

UINavigation bar background in iPhone

I have applied following code to my application to change the navigation bar image.

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    [self.navigationController.navigationBar setTintColor:[UIColor blackColor]];
    [self setNavigationBarTitle];
}

-(void)setNavigationBarTitle {
    UIView *aViewForTitle=[[[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 45)] autorelease];
    UIImageView *aImg=[[UIImageView alloc] initWithFrame:CGRectMake(-8, 0, 320, 45)];
    aImg.image=[UIImage imageNamed:@"MyTabBG.png"];
    [aViewForTitle addSubview:aImg]; [aImg release]; 
    UILabel *lbl=[[[UILabel alloc] initWithFrame:CGRectMake(0, 0, 305, 45)] autorelease];
    lbl.backgroundColor=[UIColor clearColor]; lbl.font=[UIFont fontWithName:@"Trebuchet MS" size:22];
    lbl.shadowColor=[UIColor blackColor]; [lbl setShadowOffset:CGSizeMake(1,1)];
    lbl.textAlignment=UITextAlignmentCenter; lbl.textColor=[UIColor whiteColor]; lbl.text=@"Mobile Tennis Coach Overview";
    [aViewForTitle addSubview:lbl];
    [self.navigationItem.titleView addSubview:aViewForTitle];
}

See the following images. You can see the problem that I am facing.

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Each view controller of my application has above methods to set the navigation bar background.

However, when I push a new view controller to my application. Back button will be appear.

I need back button to be appear. But the image should be behind back button.

Solution

  • After an annoying night, I found a slight tweak to this, if you use drawLayer. With drawRect, when you play a video, or youtube video, the navbar is replaced with the image. And I read a few posts that this caused their app to be rejected.

    @implementation UINavigationBar (UINavigationBarCategory)

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx 
{
   if([self isMemberOfClass:[UINavigationBar class]])
   {
     UIImage *image = [UIImage imageNamed:@"navBarBackground.png"];
     CGContextClip(ctx);
     CGContextTranslateCTM(ctx, 0, image.size.height);
     CGContextScaleCTM(ctx, 1.0, -1.0);
     CGContextDrawImage(ctx,
     CGRectMake(0, 0, self.frame.size.width, self.frame.size.height), image.CGImage); 
   }
   else 
   {        
     [super drawLayer:layer inContext:ctx];     
   }
}  
@end

    If this article is accurate, all should be fine with this approach: http://developer.apple.com/iphone/library/qa/qa2009/qa1637.html