Question

I have an application that I am building, that has a PageControl with several created TabSheets, on which I place on of several pre-defined frames. There is a routine in each frame called “GetValue” that parses the contents of it’s controls into a string and returns the result. On the main form (RGMain) I have:

Type
   TGetValueFunction = Function: String;
...   
Private
   fGetValueFunction: TGetValueFunction;
...      
Public
   Property GetValueFunction: TGetValueFunction Write fGetValueFunction;

In each of the Frames I have:

Public
Constructor Create(AQwner: TComponent);
...
Interface
Constructor TBooleanChoiceFrame.Create(AOwner: TComponent);
   Begin
   Inherited Create(AOwner);
   RGMain.GetValueFunction := GetValue; <<<< compile error on this line
   End;

E2009 Incompatble types: ‘regular procedure and method pointer’

Beyond correcting the problem, is this even the correct way to solve the problem of getting access to the GetValue routine in each frame?

Answer 1

If you want to use methods of a class you have to declare the function type like this:

Type
   TGetValueFunction = Function: String of object;