Question

How do you add a method to the UIImage class in xcode 4? I want to add a scaling method that doesn't give grainy images.

Answer 1

You need to add a category. Categories look something like this:

@interface UIImage (Scaling)
{
}

- (id)scaleToWidth:(int)width height:(int)height
@end

@implementation UIImage (Scaling)

- (id)scaleToWidth:(int)width height:(int)height {
// ... code ...
}

@end