Need help with Android Sample application

Hi ,
I am a .NET developer and i need to develop an small sample app in android which should have a screen with a button say click ,and the button should change its color when user clicks on it. I have never done java development or android . I need this app to demonstrate to a small group as to how mobile applications can work on a device. Can anybody please guide me in this thing. Also, I am planning to look into the source code and start my android development from there.

Thanks in advance

I'd start with one of the sample apps that come with the Android SDK. The docs that come with the SDK walk you through some of those.

A forum discussion in unsutable for getting you up to speed on this huge topic. Not sure if there's a book on Android for Java novices; check out the books listed in http://www.coderanch.com/how-to/java/AndroidFaq.