Programming Windows®, Fifth Edition

Building a Better Scroll

SYSMETS2 works well, but it’s too inefficient a model to be imitated in other programs. Soon I’ll present a new version that corrects its deficiencies. Most interesting, perhaps, is that this new version will not use any of the four scroll bar functions discussed so far. Instead, it will use new functions unique to the Win32 API.

The Scroll Bar Information Functions

The scroll bar documentation (in /Platform SDK/User Interface Services/Controls/Scroll Bars) indicates that the SetScrollRange, SetScrollPos, GetScrollRange, and GetScrollPos functions are “obsolete.” This is not entirely accurate. While these functions have been around since Windows 1.0, they were upgraded to handle 32-bit arguments in the Win32 API. They are ...