I want that height of elements should be adjusted automatically at run time based on the size of element..
For that I have used Height : auto;
But it is not working...
So which property should I use?

I assume you are using height in your DIV,

don't mention height. It will automatically adjust according to the contents.

But hard to suggest without seeing the css

Ya I have used <div class="addWidget">
and in css .addWidget{ height:auto;}
And I also tried as u said...but no result...

Try add "overflow:hidden" to its wrapper container