How to fix scrollbars when resizing a window or container?

Question

Currently, in my application, I am using HScrollBar and VScrollBar to pan in a large image. Part of the displayed image is based on the value of the scroll property. However, if you resize the SplitContainer or resize the form window, the scrollbar value does not automatically update and may display something off-screen.

At this point, I noticed that if you press the scroll arrow, it will magically lock the scroll bar. I was wondering if there is a way to simulate clicking a scrollbar for this in the Form_Resize and SplitContainer_Resize event handlers, but I could not find anything.

To manually adjust the scrollbar value in all size changes, it happens slow, ugly and doesn't work. I would really like the scroll bar to simply automatically lock itself when the window changes, like when you click on the arrow, but I'm not sure how to do it.

Answer 1

Try calling the Invalidate() scroll method in the form resize handler:
http://msdn.microsoft.com/en-us/library/system.windows.forms.control.invalidate.aspx

This should result in a correct redraw after changing the shape.

Answer 2

Use something like this:

 HScrollBarObject.SetStyle(ControlStyles.ResizeRedraw, true);