How to create MDI windows
It’s possible to create MDI windows with the IDE by respecting the following rules:
• Each MDI window should be managed by a separate program.
• The program that hosts the MDI-PARENT window must call the programs that host the MDI-CHILD windows passing the window handle to them as parameter.
• The programs that host the MDI-CHILD window must include a data item of type handle of window in order to receive the MDI-PARENT window handle. Such data item must be used to set the field "upon variable" among Variables of the Screen.
Steps to create an MDI-PARENT window:
1. Work in Structural View
2. Expand Screen Section of the desired program
3. Select the Screen that you want to make an MDI-PARENT
4. Among Properties, set "window type" to "MDI-PARENT".
Steps to create an MDI-CHILD window:
1. Work in Structural View
2. Expand Screen Section of the desired program
3. Select the Screen that you want to make an MDI-CHILD
4. Among Properties, set "window type" to "MDI-CHILD"
5. Among Variables, set "upon variable" to the Linkage Section data item that receives the MDI-PARENT window handle.