Question

in my .h I have

IBOutlet NSMutableArray *buttons;
@property (nonatomic, retain) IBOutletCollection(UIButton) NSMutableArray *buttons;
-(void)play:(UIButton *)theButton;

in my .m I have

-(void)initButtons{
buttons = [[NSMutableArray alloc] initWithCapacity:1];
UIButton *myBut = [UIButton alloc];
[buttons addObject: myBut];
[[buttons objectAtIndex:0] addtarget:self action@selector(play:) forControlEventTouchUpInside];
}

…

-(void)dealloc{
[buttons dealloc];
[super deallloc];
}

…..

-(void)viewDidLoad{
[super viewDidLoad];
[self initButtons];
}

I dragged the buttons IBoutletCollection in interface builder to a simple button, but when I test it it doesn’t perform the expected action;

I should mention that if I turn my action into (IBAction) instead of (void) and link it to the button it works;

I don’t understand very well NSArrays and outlet collections.

Answer 1

The array is set for you with whatever buttons you’ve connected to the collection in the NIB. It fails to do anything because you’ve reset the ivar here:

buttons = [[NSMutableArray alloc] initWithCapacity:1];

…or because you’ve not connected buttons to the collection.