Reserve part of the desktop

How can I reserve one edge of the desktop with Delphi? Something like the Vista Sidebar does.

What you want is called an application desktop toolbar

You must use the TAppBarData Object declared in the ShellAPI unit and the SHAppBarMessage function.

See this simple example.

type
  TApplicationTaskBar = class(TForm)
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  private
    procedure CreateParams(var Params: TCreateParams); override;
  public
    { Public declarations }
  end;

var
  ApplicationTaskBar: TApplicationTaskBar;

implementation

{$R *.dfm}

Uses
ShellAPI;

procedure TApplicationTaskBar.CreateParams(var Params: TCreateParams);
begin
  inherited;
  Params.ExStyle  := Params.ExStyle or WS_EX_TOOLWINDOW;
  Params.Style    := (Params.Style OR WS_POPUP) AND (NOT WS_DLGFRAME);  //Remove title Bar
end;

procedure TApplicationTaskBar.FormCreate(Sender: TObject);
var
  MyTaskBar  : TAppBarData;
begin
  GlassFrame.Enabled       :=True;//Activate Glass  , optional
  GlassFrame.SheetOfGlass  :=True;//optional
  Left:=0;
  Top :=0;
  Width := 300;
  Height:= Screen.Height;
  FillChar(MyTaskBar, SizeOf(TAppBarData), 0);
  MyTaskBar.cbSize := SizeOf(TAppBarData);
  MyTaskBar.hWnd   := Handle;
  MyTaskBar.uCallbackMessage := WM_USER+777;  //Define my own Mesaage
  MyTaskBar.uEdge  := ABE_LEFT;
  MyTaskBar.rc     := Rect(0, 0, Width, Height);
  SHAppBarMessage(ABM_NEW, MyTaskBar);
  SHAppBarMessage(ABM_ACTIVATE, MyTaskBar);
  SHAppBarMessage(ABM_SETPOS, MyTaskBar);
  Application.ProcessMessages;
end;


procedure TApplicationTaskBar.FormDestroy(Sender: TObject);
var
  MyTaskBar : TAppBarData;
begin
  FillChar(MyTaskBar, SizeOf(TAppBarData), 0);
  MyTaskBar.cbSize := SizeOf(TAppBarData);
  MyTaskBar.hWnd   := Self.Handle;
  SHAppBarMessage(ABM_Remove, MyTaskBar);
end;

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