If the TOP-ONLY attribute is TRUE for the frame, no other frame can overlay it.
If more than one window is designated as TOP-ONLY, they will all stay on top of all non-TOP-ONLY windows, but each can be brought to the foreground. That is, a TOP-ONLY window is always on top of all non-TOP-ONLY windows, but is not necessarily on top of all TOP-ONLY windows.
The TOP-ONLY behavior will be temporarily suspended while a dialog box is displayed to prevent the TOP-ONLY windows from covering the dialog-box.
A window cannot have both the TOP-ONLY and ALWAYS-ON-TOP attributes set to TRUE. Setting the TOP-ONLY attribute to TRUE will set the ALWAYS-ON-TOP attribute to FALSE. The default value of the TOP-ONLY attribute is FALSE.
When using .NET forms with ABL windows in an ABL session, setting this attribute to TRUE on an ABL window enables the specified window to overlay all other .NET forms and non-TOP-ONLY windows in the session. However, .NET forms do not have a corresponding property or method to specify similar behavior for a form. Thus, you cannot have a .NET form in an ABL session that overlays all other forms and windows in the session.
