how do i zoom the screen in runtime

hi,

My question is how do i zoom the screen to predefined height and width with a single click. and back to original size again with single click.

i have one trending screen (500 * 500)and one button. i want to zoom that trending screen to a (1000 * 1000) with the help of that button. and again to original size (500 * 500) with help of that same button.

please help me out.


thanks
s.