External form inclusion

In some cases, application forms can become very complex, or can have a common layout part that repeats across forms. In such case, some parts of the form can be defined in a external .per file, that will be included in the final forms by using the FORM clause inside the LAYOUT section.

Further, the external form parts can be controlled by a declarative dialog instruction that can be attached to any procedural dialog instruction, with the SUBDIALOG clause of DIALOG.

LAYOUT
  VBOX
    GRID g1
    {
       Customer information
       Name:  [f001                 ]
       ...
    }
    END
    FORM "orders"
  END
END