What is the best way to make a Delphi Application completely full screen?

Question

What is the best way to make a delphi application (delphi 2007 for win32 here) go completely full screen, removing the application border and covering windows task bar ?

I am looking for something similar to what IE does when you hit F11.

I wish this to be a run time option for the user not a design time decision by my good self.

As Mentioned in the accepted answer

BorderStyle := bsNone; 

was part of the way to do it. Strangely I kept getting a E2010 Incompatible types: 'TFormBorderStyle' and 'TBackGroundSymbol' error when using that line (another type had bsNone defined).

To overcome this I had to use :

BorderStyle := Forms.bsNone;

Solution 1

Well, this has always worked for me. Seems a bit simpler...

procedure TForm52.Button1Click(Sender: TObject);
begin
  BorderStyle := bsNone;
  WindowState := wsMaximized;
end;

Solution 2

A Google search turned up the following, additional methods:

(though I think I'd try Roddy's method first)

Manually fill the screen (from: About Delphi)

procedure TSomeForm.FormShow(Sender: TObject) ;
var
   r : TRect;
begin
   Borderstyle := bsNone;
   SystemParametersInfo
      (SPI_GETWORKAREA, 0, @r,0) ;
   SetBounds
     (r.Left, r.Top, r.Right-r.Left, r.Bottom-r.Top) ;
end;

Variation on a theme by Roddy

FormStyle := fsStayOnTop;
BorderStyle := bsNone;
Left := 0;
Top := 0;
Width := Screen.Width;
Height := Screen.Height;

The WinAPI way (by Peter Below from TeamB)

private  // in form declaration
    Procedure WMGetMinMaxInfo(Var msg: TWMGetMinMaxInfo);
      message WM_GETMINMAXINFO;

Procedure TForm1.WMGetMinMaxInfo(Var msg: TWMGetMinMaxInfo);
  Begin
    inherited;
    With msg.MinMaxInfo^.ptMaxTrackSize Do Begin
      X := GetDeviceCaps( Canvas.handle, HORZRES ) + (Width - ClientWidth);
      Y := GetDeviceCaps( Canvas.handle, VERTRES ) + (Height - ClientHeight
);
    End;
  End;

procedure TForm1.Button2Click(Sender: TObject);
Const
  Rect: TRect = (Left:0; Top:0; Right:0; Bottom:0);
  FullScreen: Boolean = False;
begin
  FullScreen := not FullScreen;  
  If FullScreen Then Begin
    Rect := BoundsRect;
    SetBounds(
      Left - ClientOrigin.X,
      Top - ClientOrigin.Y,
      GetDeviceCaps( Canvas.handle, HORZRES ) + (Width - ClientWidth),
      GetDeviceCaps( Canvas.handle, VERTRES ) + (Height - ClientHeight ));
  //  Label2.caption := IntToStr(GetDeviceCaps( Canvas.handle, VERTRES ));
  End
  Else
    BoundsRect := Rect;
end; 

Solution 3

Maximize the form and hide the title bar. The maximize line is done from memory, but I'm pretty sure WindowState is the property you want.

There's also this article, but that seems too complicated to me.

procedure TForm1.FormCreate(Sender: TObject) ;
begin
   //maximize the window
   WindowState := wsMaximized;
   //hide the title bar
   SetWindowLong(Handle,GWL_STYLE,GetWindowLong(Handle,GWL_STYLE) and not WS_CAPTION);
   ClientHeight := Height;
end;

Edit: Here's a complete example, with "full screen" and "restore" options. I've broken out the different parts into little procedures for maximum clarity, so this could be greatly compressed into just a few lines.

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    btnGoFullScreen: TButton;
    btnNotFullScreen: TButton;
    btnShowTitleBar: TButton;
    btnHideTitleBar: TButton;
    btnQuit: TButton;
    procedure btnGoFullScreenClick(Sender: TObject);
    procedure btnShowTitleBarClick(Sender: TObject);
    procedure btnHideTitleBarClick(Sender: TObject);
    procedure btnNotFullScreenClick(Sender: TObject);
    procedure btnQuitClick(Sender: TObject);
  private
    SavedLeft : integer;
    SavedTop : integer;
    SavedWidth : integer;
    SavedHeight : integer;
    SavedWindowState : TWindowState;
    procedure FullScreen;
    procedure NotFullScreen;
    procedure SavePosition;
    procedure HideTitleBar;
    procedure ShowTitleBar;
    procedure RestorePosition;
    procedure MaximizeWindow;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.btnQuitClick(Sender: TObject);
begin
  Application.Terminate;
end;

procedure TForm1.btnGoFullScreenClick(Sender: TObject);
begin
  FullScreen;
end;

procedure TForm1.btnNotFullScreenClick(Sender: TObject);
begin
  NotFullScreen;
end;

procedure TForm1.btnShowTitleBarClick(Sender: TObject);
begin
  ShowTitleBar;
end;

procedure TForm1.btnHideTitleBarClick(Sender: TObject);
begin
  HideTitleBar;
end;

procedure TForm1.FullScreen;
begin
  SavePosition;
  HideTitleBar;
  MaximizeWindow;
end;

procedure TForm1.HideTitleBar;
begin
  SetWindowLong(Handle,GWL_STYLE,GetWindowLong(Handle,GWL_STYLE) and not WS_CAPTION);
  ClientHeight := Height;
end;

procedure TForm1.MaximizeWindow;
begin
  WindowState := wsMaximized;
end;

procedure TForm1.NotFullScreen;
begin
  RestorePosition;
  ShowTitleBar;
end;

procedure TForm1.RestorePosition;
begin
  //this proc uses what we saved in "SavePosition"
  WindowState := SavedWindowState;
  Top := SavedTop;
  Left := SavedLeft;
  Width := SavedWidth;
  Height := SavedHeight;
end;

procedure TForm1.SavePosition;
begin
  SavedLeft := Left;
  SavedHeight := Height;
  SavedTop := Top;
  SavedWidth := Width;
  SavedWindowState := WindowState;
end;

procedure TForm1.ShowTitleBar;
begin
  SetWindowLong(Handle,gwl_Style,GetWindowLong(Handle,gwl_Style) or ws_Caption or ws_border);
  Height := Height + GetSystemMetrics(SM_CYCAPTION);
  Refresh;
end;

end.

Solution 4

Put to the form onShow event such code:

  WindowState:=wsMaximized;

And to the OnCanResize this:

  if (newwidth<width) and (newheight<height) then
    Resize:=false;

Solution 5

In my case, the only working solution is:

procedure TFormHelper.FullScreenMode;
begin
  BorderStyle := bsNone;
  ShowWindowAsync(Handle, SW_MAXIMIZE);
end;

View more solutions

Comments

[Alex]

+1 Sometimes people try too hard: blogs.msdn.com/b/oldnewthing/archive/2005/05/05/414910.aspx

[mistertodd]

Wow, i would not have believed it if i hadn't tested it myself. i know that setting WindowsState := wsMaximized will not cover the taskbar (it will be just a maximized window). So it was not unreasonable to assume that removing the border would lead to a maximized window with no border. But there's some undocumented trick somewhere (VCL or Windows) that removing the border of a maximized window will cause it to resize to fill the entire screen. (As opposed to Raymond's article where you explicitly size the form to the screen dimensions)

[Server Overflow]

What if you have dual monitor?

[Ninj]

Windows 7 here (64bit) + Delphi XE 7: that doesn't work. The Windows taskbar still shows. Tested on Windows 8.1: same as W7 + the action bar that you can pull from the right is still available.

[Ninj]

Edit: On Windows 7 that works (I forgot to remove the Align := alClient on the form). But on Windows 8.1 the action bar that you can pull from the right is still available. Any solution?

[Ruslan Abuzant]

What you wrote is not even close to code, missing double-dots, missing line separators, caused me a loss of 2 additional minutes when I needed a minute of acceleration. Please, either write complete useful code, or do not write at all. {code} Align := alClient; FormStyle := fsStayOnTop; {code}