UIImage view - animation view logic error xCode 4.2 - ios

Question

I am trying to make an animation that it will changes some pictures that i have already in the app.
After searching around i found something that works pretty well for me.
Code below:
- (void)viewDidLoad
{
[super viewDidLoad];
UIImageView*animationView = [[UIImageView alloc] initWithFrame:self.view.frame];
animationView.animationImages = [NSArray arrayWithObjects:
[UIImage imageNamed:#"photo1.jpg"],
[UIImage imageNamed:#"photo2.jpg"],
[UIImage imageNamed:#"photo3.jpg"], nil];
animationView.animationDuration = 5;
animationView.animationRepeatCount = 0;
[animationView startAnimating];
[self.view addSubview:animationView];
}
So even this works great for me, it gives me a logic error (the yellow triangle sign) and it says
"Local declaration of 'animationView' hides instance variable"
Even tho i run the code and it does what i want it to do, i cant understand why i have this error.
Also to note that this takes place inside an UIImage that i have declared as an outlet
And one extra question: How can i add the fadein - fadeout effect ?
Thanks in advance

Answer 1

You must have declared UIImageView *animationView as either an instance variable or a property.
You can safely remove the UIImageView * part in your viewDidLoad as there is no need to re-declare animationView as UIImageView since compiler already knows about it and that's why it gives you the warning.
So it would look like this:
- (void)viewDidLoad
{
[super viewDidLoad];
animationView = [[UIImageView alloc] initWithFrame:self.view.frame];
animationView.animationImages = [NSArray arrayWithObjects:
[UIImage imageNamed:#"photo1.jpg"],
[UIImage imageNamed:#"photo2.jpg"],
[UIImage imageNamed:#"photo3.jpg"], nil];
animationView.animationDuration = 5;
animationView.animationRepeatCount = 0;
[animationView startAnimating];
[self.view addSubview:animationView];
}

Answer 2

As for the fade effect you could do something like:
//Fade in
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
[animationView setAlpha:1];
[UIView commitAnimations];
//Fade out
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.5];
[animationView setAlpha:0];
[UIView commitAnimations];