The Destination Property (Magic xpa 3.x)
A subform can be used to display different programs at Runtime.
This is done by using a Call Operation property: Destination. When a program is called that is set to run in a subform, that program runs in the subform named in the Destination property. If another program is called to run in the same subform, the first program is closed and the second one then runs in that subform.
The Destination property can refer to a subform or a frame. It references the Control Name or Frame Name. In this example, there are three different tasks that can run in the subform, depending on the value of the Display Task variable.
Note that the Calls are Mixed side. Whenever the subtask is called, the server must be accessed. Using a Variable Change as in this example will generate a syntax warning as such calls could be inefficient.
You can also use this technique with Frames.