Question

I have a (retained) UIImage property that is being used to hold a user selected image.

This is the code I have at present when the user makes a selection:

- (IBAction) selectImage1 {
    UIImage *image = [UIImage imageNamed: @"image1-big.png"];
    self.bigImage = image;
} 

but I’m wondering if it is possible to omit the use of the temporary variable convenience method and just do this:

- (IBAction) selectImage1 {
    self.bigImage = [UIImage imageNamed: @"image1-big.png"];
} 

If there are problems with this second method (I’m guessing something to do with memory management), could someone please explain?

Thank you!

Answer 1

The second way is perfectly fine. The line UIImage *image = [UIImage imageNamed: @"image1-big.png"]; gives you a variable image that is auto-released. Assigning it to your ivar via the self.bigImage = image calls bigImage‘s setter method which retains the value. Thus the line self.bigImage = [UIImage imageNamed: @"image1-big.png"]; is equivalent to the more verbose way.