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General Discussion

Posted by Wren Howell
Wren Howell
3,582 Points

Instruct your 'imageView' to start running the animation.

On the .h file I have

import "UIViewController.h"

@interface THViewController : UIViewController

@property (nonatomic, strong) UIImageView *imageView;

[self.imageView startAnimating];

@end

and the .m file I have

import "THViewController.h"

@implementation THViewController

  • (void)viewDidLoad { [super viewDidLoad];

    // backgroundImage is a local variable UIImage *backgroundImage = [UIImage imageNamed:@"background"]; // imageView is a property self.imageView = [[UIImageView alloc] initWithImage:backgroundImage];

    // Add your code below! // Remember 'imageView' is a property // so refer to it as 'self.imageView' self.imageView.animationImages = [[NSArray alloc] initWithObjects: [UIImage imageNamed:@"01.png"], [UIImage imageNamed:@"02.png"], [UIImage imageNamed:@"03.png"], nil];

self.imageView.animationDuration = 5.0f; }

  • (void)startAnimating { }

@end

Why is it giving me an error to call the appropriate image view?

7 Answers

Patrick Serrano
Patrick Serrano
13,834 Points
Patrick Serrano
Patrick Serrano
13,834 Points

[self.imageView startAnimating]; is a method call. Method calls are done in the implementation file (the .m file) not the header file (the .h file).

Wren Howell
Wren Howell
3,582 Points
Wren Howell
Wren Howell
3,582 Points

opps, I forgot about that. So that means that I dont add anything to the .h file right?

Wren Howell
Wren Howell
3,582 Points
Wren Howell
Wren Howell
3,582 Points

I am still getting an error though. What is wrong?

Patrick Serrano
Patrick Serrano
13,834 Points
Patrick Serrano
Patrick Serrano
13,834 Points

I would suggest going back and rewatching the video on iOS animations, I think it would clear a few things up for you.

Your code still isn't working because you attempted to write your own method called startAnimating instead of calling the built-in startAnimating method on the UIImageView property.

Wren Howell
Wren Howell
3,582 Points
Wren Howell
Wren Howell
3,582 Points

I rewatched the video and am still confused. Can you show me the answer? I will try to find what I did wrong from there

Patrick Serrano
Patrick Serrano
13,834 Points
Patrick Serrano
Patrick Serrano
13,834 Points

I'm don't want to post the exact code because debugging is a big part of learning to program.

To pass this code challenge you will need to remove (void)startAnimating { } since that is not needed at all (startAnimating is provided by Apple) and then in viewDidLoad you will want to call startAnimating on the UIImageView.

Again it is all in the video if you get stuck.

Wren Howell
Wren Howell
3,582 Points
Wren Howell
Wren Howell
3,582 Points

okay. thanks!