Question

I have a Delphi form inside a DLL (I know that this restricts the use of the DLL to Delphi but this is not a problem in this case).

The DLL exports a function ShowForm that looks roughly like this:

procedure ShowForm (App : TApplication);
begin
  OldApp := Application;
  try
    Application := App;
    MyForm := TMyForm.Create (nil);
    try
      MyForm.ShowModal;
    finally
      FreeAndNil (MyForm);
    end;
  finally
    Application := OldApp;
  end;
end;

Now on the form I use a TAdvOfficeHint (from the TMS component pack). Unfortunately the hints do not show up.

Am I missing something here? How can I make the form behave exactly as it would if I showed it from the main application?

Thanks!

Answer 1

I don’t know TAdvOfficeHint but I guess it hooks Application.OnShowHint to set its own THintWindowClass, and even if both the main executable and the DLL are linking in the TMS unit, they each have their own copy of the class which is where things go wrong.

Assigning Application is not enough: there are other global variables, like Screen, Mouse, etc. Others are even hidden in the implementation so I’d say your chances to make the form behave exactly as from the main application are slim.