Is there an way to make an invisible UIButton that will still “be there” and catch touch events for my UIImageView?

Question

I thought to be clever and just put an transparent UIButton over an UIImageView with the exact frame size, so that I can wire it up easily with any event I like, for example

Answer 1

Jasons answer above is nearly correct, but setting the button type is not possible. So to programmatically create an empty button, use this code:

UIButton* myButton = [UIButton buttonWithType:UIButtonTypeCustom];
myButton.frame=frame;
[self.view addSubview:myButton];

Answer 2

In addition to UIButtonTypeCustom, I set the button text colors to the following:

[button setTitleColor:[UIColor clearColor] forState:UIControlStateNormal];
[button setTitleShadowColor:[UIColor clearColor] forState:UIControlStateNormal];
[button setTitleColor:[UIColor clearColor] forState:UIControlStateHighlighted];
[button setTitleShadowColor:[UIColor clearColor] forState:UIControlStateHighlighted];

Answer 3

This is what i did but with using a subclass of UIButton which i later found out should not be subclassed as per the net. My subclass was called Points

Points *mypoint=[Points buttonWithType:UIButtonTypeCustom];

then if you have an image you want to add to the button : [mypoint setImage:imageNamed:@"myimage"] forstate: UIControlStateNormal];

if you dont add this image then the button will be invisible to the user but should respond to touch. Thats how i created a hotspot on my imageView inorder to have it respond to user interaction.

Answer 4

lazyImageView = [[UIImageView alloc] init];

                        button=[[UIButton alloc]init];
                        [UIButton buttonWithType:UIButtonTypeRoundedRect];
                        [button addTarget:self
                                   action:@selector(aMethodForVideo:)
                         forControlEvents:UIControlEventTouchUpInside];
                        [button setBackgroundImage:[UIImage    imageNamed:@"BackTransparent.png"] forState:UIControlStateHighlighted];
                        [button setTitle:@"" forState:UIControlStateNormal];

                                lazyImageView.frame=CGRectMake(x, y, w, h);
                                button.frame=CGRectMake(x, y, w, h);

Set frame of button and Image both have same frame .I use this code and working fine.Also set button background image forState:UIControlStateHighlighted so when you click on that when you see the click effect.

Answer 5

You should be able to set the button's 'Type' to Custom in Interface Builder, and it will not display any text or graphical elements over the UIImageView. This way, you don't need to adjust the alpha. If the view is built from code, use:

button = [UIButton buttonWithType:UIButtonTypeCustom];