animating image in heart beat form by xcode

I have inserted an image in the view.No I need to set an animation in a way that it glows开发者_JS百科 on and off (like heartbeat action) when user selects that image.What will be the code for that?please help me.

Use

[imageHeartBeated setAlphaValue:0.5];

to set the alpha lower, which will make it glow "off".

I hope you're not just lazy, as one commenter pointed out, but just do not know where to start. It would be here. You should also peruse Ray Wenderlich's fabulous site, I'm pointing you at the two posts that might be of use to you for this particular purpose.