Components themselves cannot change dimensions, but what you can do is simulate this action using states.
You will need to have two identical boxes/containers, one with default dimensions and one with the dimensions you would want it to have after the button is clicked. You would the hide the first component and make the second component visible when the state changes value, similar to a popup.
If you are not familiar with states, you may want to change out this tutorial video on States: http://www.youtube.com/watch?feature=pl ... qJ9my3ubxo
If you have any questions, please let us know?