Scrolling a Bitmap with the WM_HSCROLL and WM_VSCROLL Messages
When the
WM_HSCROLL and
WM_VSCROLL messages are processed, the scroll bar notification message is examined and
the scrolling position is set to a new value that reflects the scrolling action
of the user. If the scrolling position is within the scrolling range, the
window is scrolled to the new position by using the
ScrollWindow function. The position of the scroll box is then adjusted by using the
SetScrollInfo function. In versions earlier than 4.0, use the
SetScrollPos function.
After a window is scrolled, part of its client area is made invalid. To ensure
that the invalid region is updated, use the
UpdateWindow function to generate a
WM_PAINT message. When processing the WM_PAINT message, an application must repaint
the invalid region at the bottom of the client area. When scrolling or resizing
the client area, the example uses the
BitBlt function to copy the appropriate portion of the bitmap to the invalid portion
of the client area.
- Software for developers
-
Delphi Components
.Net Components
Software for Android Developers
- More information resources
-
MegaDetailed.Net
Unix Manual Pages
Delphi Examples
- Databases for Amazon shops developers
-
Amazon Categories Database
Browse Nodes Database
