The Old New Thing

Answers to exercises from Scrollbars Part 10

September 13, 2003 Sep 13, 2003 09/13/03

Raymond Chen

Answers to exercises from Scrollbars Part 10.

Scrollbars part 10 – Towards a deeper understanding of the WM_NCCALCSIZE message

September 11, 2003 Sep 11, 2003 09/11/03

Raymond Chen

When your window is resized, Windows uses the WM_NCCALCSIZE message to determine where your window's client area lives inside your window rectangle. There are two forms of the WM_NCCALCSIZE message. The simple form merely takes a window rectangle and returns a client rectangle. This is useful for...

Scrollbars part 9 – Maintaining the metaphor

September 9, 2003 Sep 9, 2003 09/9/03

Raymond Chen

When a document is displayed with scrollbars, the metaphor is that the window is a viewport onto the entire document, only a portion of which is visible at the moment. The default behavior of a resize, however, is to maintain the origin at the upper left corner of the client area, which breaks the metaphor...

Where is my program running from?

September 5, 2003 Sep 5, 2003 09/5/03

Raymond Chen

Another common question: "How do I find out where my program is? I want to be able to access support files in that same directory." Answer: GetModuleFileName(NULL...

Case mapping on Unicode is hard

September 5, 2003 Sep 5, 2003 09/5/03

Raymond Chen

Occasionally, I'm asked, "I have to identify strings that are identical, case-insensitively.  How do I do it?" The answer is, "Well, it depends. Whose case-mapping rules do you want to use?" Sometimes the reply is, "I want this to be language-independent." Now ...

How to recognize different types of timestamps from quite a long way away

September 5, 2003 Sep 5, 2003 09/5/03

Raymond Chen

The great thing about timestamps is that there are so many to choose from.

Determining whether your window is covered

September 2, 2003 Sep 2, 2003 09/2/03

Raymond Chen

The method described in the previous coding blog entry works great if you are using the window visibility state to control painting, since you're using the paint system itself to do the heavy lifting for you. To obtain this information outside of the paint loop, use GetDC and GetClipBox...

Painting only when your window is visible on the screen

August 29, 2003 Aug 29, 2003 08/29/03

Raymond Chen

Sometimes you want to perform an activity, such as updating a status window, only as long as the window is not covered by another window. The easiest way to determine this is by not actually trying to determine it. For example, here's how the taskbar clock updates itself...