Child windows are always opened from within a main or pop-up window, which becomes the child window’s parent.
A child window exists only within its parent. You can move the child window within the parent window, but not outside the parent. When you move a portion of a child window beyond the parent, PowerBuilder clips the child so that only the portion within the parent window is visible. When you move the parent window, the child window moves with the parent and maintains the same position relative to the parent.
Child windows cannot have menus and are never considered the active window. They can have title bars and can be minimizable, maximizable, and resizable. When they are maximized, they fill the space of their parent; when they are minimized, their icon displays at the bottom of their parent.
The initial position of the child is relative to the parent and not to the entire screen. A child window closes when you close its parent.
You will probably not use child windows very often. Typically, if you want to display windows inside other windows, you will write MDI applications, where much of the window management happens automatically.
For more on building MDI applications, see Application Techniques.
