In PowerBuilder Classic, you can set docking behaviors for the sheets that open in
the MDI (multiple document interface) frame window.

• Window Types and Docking States
  New window types allow sheets to open in one of four states: docked, floating, tabbed document, or tabbed window.
• Open Sheets in a Specific State
  New versions of the OpenSheet function allow you to open a sheet at a specific docking location, in a specific tab group, or as a document.
• Persist the MDI State
  You can set the application so that, when the user launches the application, the sheets are open in the same position and state as when the user closed it.
• Properties for Dockable Windows
  Customize the behavior and appearance of the windows and tabs.