Question

I have functions I want to perform after my app has finished initialising and the main form has been created. I did have the code (call it ProcedureX) in the forms OnShow event, but I have just noticed that it is being called twice, because OnShow is firing twice. It fires when the main program DPR calls:

Application.CreateForm(TMainForm, MainForm) ;  

as I would expect. But after that, when I read stuff from an INI file that includes the forms on-screen position, I have a call:

MainForm.position := poScreenCenter ;

This, it would appear fires the OnShow event again.

Where can I put my call to ProcedureX, which must only be called once, and which needs the main form to be created before it can execute?

Answer 1

You can test and set a flag once you call the procedure for the first time. Like so:

type
  TForm1 = class(TForm)
    procedure FormShow(Sender: TObject);
  private
    FRunOnce: Boolean;
  public
    [...]

[...]

procedure TForm1.FormShow(Sender: TObject);
begin
  if not FRunOnce then begin
    FRunOnce := True;
    ProcedureX;
  end;
end;