ACTIVE-FORM system reference

ACTIVE-FORM references instances of any class that ABL recognizes as a form, including the following form classes:

Progress.Windows.Form class — A custom OpenEdge .NET form class that encapsulates a Microsoft .NET System.Windows.Forms.Form for use within an ABL session. If a .NET form is last to receive focus and you use the Progress.Windows.Form class to instantiate all .NET forms, ACTIVE-FORM references the affected Progress.Windows.Form instance.

Progress.Windows.FormProxy class — An OpenEdge .NET form class that is associated with each ABL window instantiated in any ABL session that references .NET objects. If an ABL window is last to receive focus, ACTIVE-FORM references the Progress.Windows.FormProxy object associated with the affected window.

If the last ABL window to receive focus is the default window, ACTIVE-FORM returns the Unknown value (?), because ABL does not create a FormProxy object for the default window.

You cannot use ACTIVE-FORM if the window with focus is not a Progress.Windows.Form or a native ABL window. If you directly instantiate .NET forms using System.Windows.Forms.Form (or any other native .NET form class), you must use the .NET ActiveForm property to identify the native .NET form instance that has focus. Progress.Windows.Form also inherits the ActiveForm property from System.Windows.Forms.Form, and this property also references the .NET native form instance that a given Progress.Windows.Form object represents. However, Progress.Windows.FormProxy does not inherit the ActiveForm property and does not provide a meaningful reference when an ABL window has focus.