Loading images problem HELP!

Hello there

I made 1 image gallery. and i am facing a big issue. When one image is loading in my Loader object. If i click on next image button. It starts loading another image without canceling the existing image. So mutliple images appear at stage in this case. Please help me out with this.

I want something that stops loading older image and start loading new image.

Thanks in Advance
Saurabh