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caldwelljason
Aug 1, 2008, 03:48 PM
I need a button that changes state in an animated way when the user touches it.

I have spent quite a bit of time going down the "make a UIImageView-derived control respond to touches" road with no success. I can get it to display correctly and to animate correctly, but not to respond to touches.

So I changed approaches. I am now using a UIButton-derived control. UIButton inherits UIControl, which UIImageView is not. So UIButton has an addTarget: action:... method. I figured I could use this method to capture the touch event and just add a UIImageView as a subview of the button.

No such luck. :confused: Now I get the touch events, but the image doesn't display or animate... :(

Any thoughts?



caldwelljason
Aug 1, 2008, 03:59 PM
So now I can get the UIImageView to appear as the subview of the button (I had to initialize it with a rect relative to the button, not the container, duh :p), but it is eating all the touch events!

When I used a UIImageView-derived class, I couldn't BEG it respond to touch events, they always flowed to the control behind it.

Now that I stick a UIImageView directly on a button, it is eating all of the events! Me no like.

caldwelljason
Aug 1, 2008, 04:33 PM
OK. So here's the punt of the week:

I created a UIImageView derived class to handle the drawing and animation, etc. Then, in the initialization of said class, I create a UIButton object and lay it over the UIImageView, like so:

{code}
UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 100, 25)];
[button addTarget:self action:@selector( touchedImage: ) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:button];
[button release];
{code}

So now the selector set up for the UIButton control handles the touch event and the UIImageView handles the drawing and animating.

I'm not real happy with it. Feels a little duct-tape-ish. But it works like a charm...;)