Question

I am trying an array item as a the object name.

I have 5 UIImageViews set up:

@interface miniTestViewController : UIViewController {

    NSArray *array;

    IBOutlet UIImageView *sun;
    IBOutlet UIImageView *moon;
    IBOutlet UIImageView *rain;
    IBOutlet UIImageView *snow;
    IBOutlet UIImageView *hail;
}

-(IBAction)fadeChosenImage:(id)sender;

My plist contains an array of image names: sun, moon, rain, snow, hail

In the .m VDL stub, this plist is read into an NSArray *array.

A UIButton tag selects the object at index:

-(IBAction)fadeChosenImage:(id)sender{

    NSString *image = [[NSString alloc] init];  
    image= nil;

    switch ([sender tag]) { 
        case 0: 
            image = [array objectAtIndex:[sender tag]]; 
            break; 
        case 1: 
            image = [array objectAtIndex:[sender tag]]; 
            break; 
        case 2: 
            image = [array objectAtIndex:[sender tag]]; 
            break; 
        case 3: 
            image = [array objectAtIndex:[sender tag]]; 
            break; 
        case 4: 
            image = [array objectAtIndex:[sender tag]]; 
            break; 
        default: 
            break;
    }

I need to use the NSString as the UIImageView object name, like this:

[[array objectAtIndex:[sender tag]] setAlpha:0];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:6.0];
[[array objectAtIndex:[sender tag]] setAlpha:1];

but so far objectAtIndex returns a NSString which does not respond to the setAlpha message.

Is it possible to convert/wrap/cast/use the NSString to the object name of the UIImageVIew

Thank you very much for any help.

Answer 1

It would be much easier to save your image view objects into the array directly, rather than trying to retrieve them using a string.

If you want to find objects using a string as a key, store them in a dictionary.

Hoever, in your case, you have a numeric index. Just save the UIImageView objects directly into your array. That does not duplicate the objects – it just saves references to them in your array.