Question

I have an array (called array in the code below) which contains a number of MyView objects. I am trying to iterate through these objects in a For loop and add them as a subview one by one, each after a delay of one second. The problem with the code below is that all the objects are added at once after a delay of one second. Can anyone suggest how I can correct ?

Thank you in advance.

- (void)startMethod {

    for (MyView * myview in array) {

        [self performSelector:@selector(addSubView:) withObject:myview afterDelay:1];
    }
}

- (void)addSubView : (UIView *)view {
    [soundController playSound];
    [self.view addSubview:view];
}

Answer 1

The time to execute the loop isn’t enough to delay selectors perform. You probably need to delay yourself using for example a counter.

-(void)startMethod {
    NSUInteger i = 0;
    for (MyView * myview in array) {
        i += 1;
        [self performSelector:@selector(addSubView:)
                   withObject:myview
                   afterDelay:i];
    }
}