Question

Adding a button to the bottom right of the screen:

    UIButton *testBtn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [testBtn addTarget:self action:@selector(test:) forControlEvents:UIControlEventTouchUpInside];

    CGRect screenRect = [[UIScreen mainScreen] bounds];
    CGFloat screenWidth = screenRect.size.width;
    CGFloat screenHeight = screenRect.size.height;

    testBtn.frame = CGRectMake(screenWidth - 100, screenHeight - 100, 100, 100);

    [self.view addSubview:testBtn];

I can see the button, and tapping it turns it blue momentarily. It just doesn’t call the test: method. Why not?

EDIT – here’s the target method:

- (void)test:(id)sender {
    NSLog(@"hi");
}

Answer 1

1. Your instance is called lockBtn but you are adding a target to btn.
2. Your method signature may be @selector(test) and not @selector(test:).