Question

I’m using an if statement to set a UIImageView‘s image depending on the value of a variable. This is the statement:

- (void)configureView
{    
    if (self.detailItem) {
        if ([detailItem isEqualToNumber:[NSNumber numberWithInt:0]]) {
            [mapImageView setImage:[UIImage imageNamed:@"0.jpg"]];
            NSLog(@"derp");
        }
    }
}

“derp” gets printed but the UIImageView‘s image won’t change… If I put the setImage: statement in viewDidLoad it works fine. What am I doing wrongly?

Answer 1

My guess is you’re calling the configureView method from a view controller’s init method.

At that point the view controller’s view has not been loaded, and the outlets for its subviews will still be nil.

Calling it from any of:

awakeFromNib
viewDidLoad
viewWillAppear:
viewDidAppear:

will work.

Try assigning

UIImage * image = [UIImage imageNamed:@"0.jpg"]

put a breakpoint there, and then look at the value in image, to make it’s being assigned correctly.