iphone - animation in the simulator works fine but in device nothing happens?

-(void) DownRoll1 { 
    down1.image = up1.image;
    [UIView beginAnimations:nil context:nil开发者_JAVA技巧];
    [UIView setAnimationDuration:2.2];
    CGPoint destination = CGPointMake(296,440);
    down1.center = destination;
    [UIView commitAnimations];
}

Answer was: check that your filenames will match on the case-sensitive device.

if you want to make something happen more quickly when the user hits the "shuffle" button, you could pre-load the image in your viewDidLoad method, and just not show it until later.