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iOS

Posted by Austin Gonzalez
Austin Gonzalez
2,377 Points

Crystal ball code challenge background image iOS

Hey guys, So I have been stuck on the code challenge for Programming a Background Image for the Crystal Ball iPhone App. I have been trying to get this right and there are already two discussions on this topic but they don't seem to answer the question. Here's what is required: Our Random Quotes app is looking bland and we need to add a background image to it. We started to create a UIImageView, however, the code does not seem to work. Figure out what is wrong and if you need to declare another object to complete this declaration.

This is what I have so far but I don't know how to proceed. It keeps on giving me an error saying “use of undeclared identifier self” but it works in xcode.

UIImage *backgroundImage = [UIImage imageNamed:@"background"];

UIImageView *imageView = [[UIImageView alloc] initWithImage:@"background"];

[self.view insertSubview:imageView atIndex:0];

So, let me know if I’m missing something. Thanks.

3 Answers

John W
John W
21,558 Points
John W
John W
21,558 Points

Here's the signature for UIImageView's initWithImage:

- (id)initWithImage:(UIImage *)image

As you can see, the argument it takes is an UIImage object, and what you have in your code (@"background") is only an NSString. Replace that with the UIImage you declared earlier and you'll be all set.

Austin Gonzalez
Austin Gonzalez
2,377 Points

thanks it worked

Nabin Bhattarai
Nabin Bhattarai
1,385 Points
Nabin Bhattarai
Nabin Bhattarai
1,385 Points

Here's the complete solution: UIImage *backgroundImage = [UIImage imageNamed:@"background"];

UIImageView *imageView = [[UIImageView alloc] initWithImage:backgroundImage];

Mark Rabo
Mark Rabo
6,260 Points
Mark Rabo
Mark Rabo
6,260 Points

Why doesn't the UIImage object require an 'alloc'?