NOTIFY Submessages (Passed in Data)

• NOTIFY_CHILDKILLED (0): This submessage is sent to a parent window when a child is killed if it needs to report something in particular. NOTE: the Window parameter which the parent window's handler receives actually points to the child window that was destroyed. Normally, this points to the window itself.
• NOTIFY_UPDATE (1): This submessage is sent to a window handler by an application to tell the window to notice a change in its data. This forces the handler to reinitialize any pertinent variables and redraw itself.
• NOTIFY_CHILDCHANGED (2): This submessage is sent to a parent window when a child changes state. In this way the parent can keep track of a child window's processing. Note that the extra parameter of this message is set to the address of the child window's LHWINDOW structure.
• NOTIFY_SORT (3): This submessage is sent to ListBox windows to have them sort their contents. The extra field specifies the sort order (=0 : ascending, !=0 : descending). The window redraws itself as a result.
• NOTIFY_USER (256): Any applicaton defined submessages should have values starting at NOTIFY_USER. Application defined submessages can be used for inter-window communications, i.e., as a way for various window handlers to converse with one another.