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Annotation of q_a/samples/subclass/readme.txt, revision 1.1.1.2

1.1       root        1:  Sample: SUBCLASS Program Demonstration
                      2: 
                      3: Summary:
                      4: 
                      5: The SUBCLASS sample demonstrates how a program can subclass
                      6: standard controls in order to extend their normal
                      7: functionality. This sample replaces the window procedure for
                      8: buttons, edit fields, and list boxes.
                      9: 
                     10: More Information:
                     11: 
                     12: The standard subclassing technique is to replace the window
                     13: procedure in the window structure by using:
                     14: 
1.1.1.2 ! root       15:    SetWindowLong (hwnd, GWL_WNDPROC, (LONG) SubclassWndProc);
1.1       root       16: 
                     17: In the SUBCLASS sample, the old window procedure is also
                     18: saved in a structure pointed at by the user data. Thus, any
                     19: functionality can be added to various classes of windows
                     20: without having to know what the class originally was.
                     21: 
                     22: In this sample, the subclass procedure adds the ability to
                     23: move and size the control windows when the application is
                     24: not in "test mode." When the application is in test mode,
                     25: the subclass procedure calls the original window procedure
                     26: and the controls behave as normal. Thus, this sample
                     27: provides the bare bones for a "dialog editor" type of
                     28: program.
                     29: 
1.1.1.2 ! root       30: Additional reference words: CallWindowProc

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