How to show tickmark on image when it is selected

i want to show a tick mark on each picture which is selected. i ha开发者_开发问答ve no idea about that.can anyone help me.

place a uibutton programmatically on the same location ad of selected picture .The button will be a custom button having transparent tick.png image.

Use need to use UIButton and two different set of images for more have a look to the below post,

Blog tutorial.

http://weheartgames.com/2009/06/simple-iphone-checkbox/

SO post,

Checkbox in iOS application

http://www.iphonedevsdk.com/forum/iphone-sdk-development/40592-any-way-make-uibutton-latch.html