How do i get my splash screen to display only once

Hi,
Here's a way to do it. It has not been tested for typos:

Unit MySplashForm;

Uses ...reg;
  ...
  ...

procedure Splash;
begin
  with TRegistry.Create do
  begin
    if ( OpenKey( '\software\mybasekey\mykey', False ) and ValueExists( 'MyValue' ) and ReadBool( 'MyValue' ) ) then
    begin
      Self.Free; // or something
    end else
    begin
      Show;
      Update;
      OpenKey( '\software\mybasekey\mykey', True );
      WriteBool( 'MyValue', True );
    end;
    Free; // TRegistry class instance
  end;
end;

/// John

Hello Igor!

   Thank's for replying, I can get a splash screen to display with code listed about but. How do add the code to the project source!! here is the code I am trying to add it to.

================================================================
Splash.dpr
================================================================
program TSplash;

uses
  Forms,
  Unit1 in 'Unit1.pas' {Form1},
  Splash in 'Splash.pas' {SplashScreen};

{$R *.RES}

begin
   try
    SplashScreen := TSplashScreen.Create(Application);
    SplashScreen.Show;
    SplashScreen.Update;
    Application.Initialize;
    Application.CreateForm(TForm1, Form1);
  Repeat
      Application.ProcessMessages;
       Until SplashScreen.CloseQuery;
      SplashScreen.Close;
     finally
    SplashScreen.Free;
  end;
  Application.Run;
end.


================================================================
Splash.pas
================================================================

unit Splash;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ExtCtrls, StdCtrls, jpeg;

type
  TSplashScreen = class(TForm)
    Timer1: TTimer;
    Image1: TImage;
    procedure Timer1Timer(Sender: TObject);
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  SplashScreen: TSplashScreen;

implementation

{$R *.DFM}

procedure TSplashScreen.Timer1Timer(Sender: TObject);
begin
Timer1.Enabled := False;
end;

procedure TSplashScreen.FormCloseQuery(Sender: TObject;
  var CanClose: Boolean);
begin
CanClose := Not Timer1.Enabled;
end;

end.


How Can i Add the code above to this code i already have. i tryied to add it but i crash splash.exe everytime.  Thank's Hyper66

                                                     
 

Adjusted points to 150

So first lets change our checking proc as

function DoISplash:boolean;
var
  T : TRegistry;
const
  MyKey = 'SOFTWARE\Hyper66\testkey';
begin
  T :=TRegistry.Create;
  try
    T.RootKey := HKEY_LOCAL_MACHINE;
    Result := not T.KeyExists(MyKey);
    if Result then
      T.CreateKey(MyKey);
    T.CloseKey;
  finally
    T.Free;
  end;
end;

so in your main proc code you can do the following:

var
  doI : boolean;
begin
 DoI := DoISplash;
 try
   if DoI then
   begin
     SplashScreen := TSplashScreen.Create(Application);
     SplashScreen.Show;
     SplashScreen.Update;
   end;
   Application.Initialize;
   Application.CreateForm(TForm1, Form1);
   if DoI then
   begin
     Repeat
       Application.ProcessMessages;
     Until SplashScreen.CloseQuery;
     SplashScreen.Close;
   end;
  finally
   if DoI then SplashScreen.Free;
  end;
  Application.Run;
end.

but it is more convinient to do the following modifications

1 - In the splash form delete Closequerry and Add just OnClose event and inside it set
    Action := caFree;
    also modify TimerEvent as follows
procedure TSplashScreen.Timer1Timer(Sender: TObject);
begin
  Enabled := false;
  Close;
end;
    so when the timer expires the form is closed and freed
2 - Use the following code (the form automatically destroy itself)
.
begin
 if DoISplash then
 begin
   SplashScreen := TSplashScreen.Create(nil);
   SplashScreen.Show;
   SplashScreen.Update;
 end;
 Application.Initialize;
 Application.CreateForm(TForm1, Form1);
 Application.Run;
end.

regards, igor

Thank's, Igor I could'nt get it to work with T.RootKey := HKEY_LOCAL_MACHINE; but the code work's great without Rootkey any ideas why???