winapiwindowparentowner

Win32 window Owner vs window Parent?


In Win32 programming, what is the difference between a window's parent and a window's owner? I thought I had it figured out, then I came across this code:

SetWindowLong(handle, GWL_HWNDPARENT, foo);

This actually sets the window's owner, not the parent - despite the GWL_HWNDPARENT being used. Are the terms parent/owner interchangeable, or is there actually a difference?


Solution

  • Owner is the Window* responsible for a control or dialog (for example, responsible for creating/destroying the window).

    Parent is the next-senior window* to a control or dialog in the window chain, but isn't actually responsible for it (doesn't necessarily care about its lifecycle, etc). A window's parent can also be its owner.

    *Window vs window: Window is an actual window displayed on the screen; window is any object with a HWND (includes buttons, panels, etc).