Size of the ScrollBar box

Dear Code Gurus,

I am trying to use the ScrollBar and want to vary the size of the ScrollBar Box (to proportianally match it with the part of the image being displayed). Is there a way to do it?

Thank you.

Dear Code Gurus,

I am trying to use a ScrollBar and want to vary the size of the ScrollBar Box (to proportianally match it with the part of the image being displayed). Is there a way to do it? I can see the ways to change maximums and minimums of the ScrollBar but what about the box size?

Thank you.