Returned Context ID – Call Operation (Magic xpa 4.x)
The Returned Context Id property is enabled for Call Program, Call Exp, and Call Public operations. This property returns the name of the new context. This property is optional.
You can manually enter a variable or zoom from this field to select an Alpha variable. The variables can be chosen from any parent program, including the Main Program.
If the attribute of the variable is neither Alpha nor Unicode, Magic xpa will clear the field.
When you use the Returned Context Id property, the Form property in the Call operation is ignored.
This property is generally used when you want two programs to be able to refer to one another. For example, if Program A calls Program B, and you have set a name in the Returned Reference Name property, then the name of Program B will be returned to Program A. See the Event Posting Between Contexts topic.
The Returned Context Id is unique and dynamic for each context. Therefore, you can use it when you want to differentiate between a number of contexts from the same program (when the same program is executed more than once). In these cases, the context ID is better than the context name (which is useful when the program is only executed once).
If the CtxSetName function is used in the Task Prefix of the called program (or its Main program), it will not be returned in this property. This is because the Context ID is set when the context loads and the Task Prefix is available once the context has already been loaded.
If you change the name of a context using the CtxSetName, you should be aware that the context name may no longer be unique. This may cause a problem when interacting between contexts.