How can I have a DLL write data to my application's form? (eg. DLLs and procedural type question)

jklimek_at_gmail.com
Date: 12/30/04 

Date: 30 Dec 2004 13:14:16 -0800

I'm trying to have a DLL write to a Form from inside an application.
The way I'm trying to do this is by using a procedural type and then
passing it in as a variable to my DLL.

Here are some code snippets:

// [FROM THE APPLICATION .EXE]
type TStrProc = procedure(s : String);
type TProc = procedure(proc : TStrProc);
var DllTest : TProc;

// eg. load the library, etc, etc...
// ...

@DllTest := GetProcAddress(LibHandle, 'DllTest');

// ...
DllTest(@DisplayIt); // this should pass the address of my local
procedure (DisplayIt) to the DLL.

--------------

// [FROM THE DLL]
type TProc = Procedure(s : String);

// ...
procedure DllTest(proc : TProc); stdcall;
begin
proc('This should be displayed on my main application's form.');
end;

--------------

However, when I run this program I am getting an Access Violation
(Access Violation at address 008D1AA3. Write of address 0000000000.)
What am I doing wrong?

Thanks,
John

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