...buttons are being added.? Actually i got an already build project's source code. Now i have to add some other functionality in that project. But while editing the projects source code..its not building/ updating the R.java file. I tried everything...saved the project and rebuild it thousand times...but its not accepting any new addition of buttons or any other elements.

when i use R.id. it show all ids but not wat i newly added in it...i rebuilt the project many many times but no result...while every other project in my eclipse id is working very fine..its just this project which is not working.
Dont know wat to do...i even copy pasted everything from the project and made a new project but still the problem is same.
@Peter : if there would hav been any unusual xml then it should have showed errors...but it isnt showing any errors

Thanks Peter...i will try doing the way you have told....
Problem Resolved --- I downloaded latest version of Eclipse and updated it with new android plugins.............and it worked...now R.java is updating itself regularly.