delphi - Cómo implementar un botón de cerrar para una TTabsheet de un TPageControl

Question

¿Cómo puedo implementar un botón de cerrar para una TTabsheet de un TPageControl como Firefox?

Editar:
Versión de Delphi: Delphi 2010
Sistema operativo: Windows XP y hasta

Answer 1

A menudo es una buena idea implementarlo usted mismo, como han sugerido las otras respuestas. Sin embargo, en caso de que ya esté utilizando Raize Components , esta característica se admite "de fábrica". Simplemente configure TRzPageControl.ShowCloseButtonOnActiveTab := true y maneje el evento OnClose . El componente se encarga de la ubicación para una variedad de diseños / orientaciones / formas / colores de pestaña.

[solo un cliente feliz]

Answer 2

Lo que hice en el pasado es simplemente poner un TBitBtn con un gráfico en la esquina superior derecha de TPageControl. El truco es que el padre del TBitBtn es el mismo que el TPageControl, por lo que no está realmente en una de las hojas de pestañas. Luego, en el clic incluso para ese botón:

PageControl1.ActivePage.Free;

Cuando se libera el TTabControl actual, notifica al TPageControl que lo posee.

Answer 3

¡Ahora con compatibilidad con temas (incluye Windows, UxTheme, Themes unidades de Windows, UxTheme, Themes )!

type
  TFormMain = class(TForm)
    {...}
  private
    FCloseButtonsRect: array of TRect;
    FCloseButtonMouseDownIndex: Integer;
    FCloseButtonShowPushed: Boolean;
    {...}
  end;

{...}

procedure TFormMain.FormCreate(Sender: TObject);
var
  I: Integer;
begin
  PageControlCloseButton.TabWidth := 150;
  PageControlCloseButton.OwnerDraw := True;

  //should be done on every change of the page count
  SetLength(FCloseButtonsRect, PageControlCloseButton.PageCount);
  FCloseButtonMouseDownIndex := -1;

  for I := 0 to Length(FCloseButtonsRect) - 1 do
  begin
    FCloseButtonsRect[I] := Rect(0, 0, 0, 0);
  end;
end;

procedure TFormMain.PageControlCloseButtonDrawTab(Control: TCustomTabControl;
  TabIndex: Integer; const Rect: TRect; Active: Boolean);
var
  CloseBtnSize: Integer;
  PageControl: TPageControl;
  TabCaption: TPoint;
  CloseBtnRect: TRect;
  CloseBtnDrawState: Cardinal;
  CloseBtnDrawDetails: TThemedElementDetails;
begin
  PageControl := Control as TPageControl;

  if InRange(TabIndex, 0, Length(FCloseButtonsRect) - 1) then
  begin
    CloseBtnSize := 14;
    TabCaption.Y := Rect.Top + 3;

    if Active then
    begin
      CloseBtnRect.Top := Rect.Top + 4;
      CloseBtnRect.Right := Rect.Right - 5;
      TabCaption.X := Rect.Left + 6;
    end
    else
    begin
      CloseBtnRect.Top := Rect.Top + 3;
      CloseBtnRect.Right := Rect.Right - 5;
      TabCaption.X := Rect.Left + 3;
    end;

    CloseBtnRect.Bottom := CloseBtnRect.Top + CloseBtnSize;
    CloseBtnRect.Left := CloseBtnRect.Right - CloseBtnSize;
    FCloseButtonsRect[TabIndex] := CloseBtnRect;

    PageControl.Canvas.FillRect(Rect);
    PageControl.Canvas.TextOut(TabCaption.X, TabCaption.Y, PageControl.Pages[TabIndex].Caption);

    if not UseThemes then
    begin
      if (FCloseButtonMouseDownIndex = TabIndex) and FCloseButtonShowPushed then
        CloseBtnDrawState := DFCS_CAPTIONCLOSE + DFCS_PUSHED
      else
        CloseBtnDrawState := DFCS_CAPTIONCLOSE;

      Windows.DrawFrameControl(PageControl.Canvas.Handle,
        FCloseButtonsRect[TabIndex], DFC_CAPTION, CloseBtnDrawState);
    end
    else
    begin
      Dec(FCloseButtonsRect[TabIndex].Left);

      if (FCloseButtonMouseDownIndex = TabIndex) and FCloseButtonShowPushed then
        CloseBtnDrawDetails := ThemeServices.GetElementDetails(twCloseButtonPushed)
      else
        CloseBtnDrawDetails := ThemeServices.GetElementDetails(twCloseButtonNormal);

      ThemeServices.DrawElement(PageControl.Canvas.Handle, CloseBtnDrawDetails,
        FCloseButtonsRect[TabIndex]);
    end;
  end;
end;

procedure TFormMain.PageControlCloseButtonMouseDown(Sender: TObject;
  Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
  I: Integer;
  PageControl: TPageControl;
begin
  PageControl := Sender as TPageControl;

  if Button = mbLeft then
  begin
    for I := 0 to Length(FCloseButtonsRect) - 1 do
    begin
      if PtInRect(FCloseButtonsRect[I], Point(X, Y)) then
      begin
        FCloseButtonMouseDownIndex := I;
        FCloseButtonShowPushed := True;
        PageControl.Repaint;
      end;
    end;
  end;
end;

procedure TFormMain.PageControlCloseButtonMouseMove(Sender: TObject;
  Shift: TShiftState; X, Y: Integer);
var
  PageControl: TPageControl;
  Inside: Boolean;
begin
  PageControl := Sender as TPageControl;

  if (ssLeft in Shift) and (FCloseButtonMouseDownIndex >= 0) then
  begin
    Inside := PtInRect(FCloseButtonsRect[FCloseButtonMouseDownIndex], Point(X, Y));

    if FCloseButtonShowPushed <> Inside then
    begin
      FCloseButtonShowPushed := Inside;
      PageControl.Repaint;
    end;
  end;
end;

procedure TFormMain.PageControlCloseButtonMouseLeave(Sender: TObject);
var
  PageControl: TPageControl;
begin
  PageControl := Sender as TPageControl;
  FCloseButtonShowPushed := False;
  PageControl.Repaint;
end;

procedure TFormMain.PageControlCloseButtonMouseUp(Sender: TObject;
  Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
  PageControl: TPageControl;
begin
  PageControl := Sender as TPageControl;

  if (Button = mbLeft) and (FCloseButtonMouseDownIndex >= 0) then
  begin
    if PtInRect(FCloseButtonsRect[FCloseButtonMouseDownIndex], Point(X, Y)) then
    begin
      ShowMessage(''Button '' + IntToStr(FCloseButtonMouseDownIndex + 1) + '' pressed!'');

      FCloseButtonMouseDownIndex := -1;
      PageControl.Repaint;
    end;
  end;
end;

Parece:

Answer 4

He cambiado un poco este ejemplo: - creado clase TCloseTabSheet - esta clase tiene propiedad OnClose: TNotifyEvent, que se llamará si está asignado - si TabSheet de TPageControl no es esa clase, entonces no hay botón de cierre - si es entonces Button mostró. Cuando presiona el botón Cerrar llama a OnClose - ahora no necesita controlar la matriz FCloseButtonsRect, causa que estos Rects se almacenen en TCloseTabSheet

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ComCtrls, Themes, Math, ExtCtrls, StdCtrls;

type TCloseTabSheet=class(TTabSheet)
  private
  protected
    FCloseButtonRect: TRect;
    FOnClose: TNotifyEvent;
    procedure DoClose; virtual;
  public
    constructor Create(AOwner:TComponent); override;
    destructor Destroy; override;
property OnClose:TNotifyEvent read FOnClose write FOnClose;
end;

type
  TMainForm = class(TForm)
    PageControlCloseButton: TPageControl;
    TabSheet1: TTabSheet;
    TabSheet2: TTabSheet;
    TabSheet3: TTabSheet;
    procedure FormCreate(Sender: TObject);
    procedure PageControlCloseButtonDrawTab(Control: TCustomTabControl; TabIndex: Integer;
      const Rect: TRect; Active: Boolean);
    procedure PageControlCloseButtonMouseDown(Sender: TObject;
      Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
    procedure PageControlCloseButtonMouseMove(Sender: TObject;
      Shift: TShiftState; X, Y: Integer);
    procedure PageControlCloseButtonMouseLeave(Sender: TObject);
    procedure PageControlCloseButtonMouseUp(Sender: TObject;
      Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
    procedure CloseTabeProc(Sender: TObject);
  private
    FCloseButtonMouseDownTab: TCloseTabSheet;
    FCloseButtonShowPushed: Boolean;
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation

{$R *.dfm}

constructor TCloseTabSheet.Create(AOwner:TComponent);
begin
  inherited Create(AOwner);
  FCloseButtonRect:=Rect(0, 0, 0, 0);
end;

destructor TCloseTabSheet.Destroy;
begin
  inherited Destroy;
end;

procedure TCloseTabSheet.DoClose;
begin
  if Assigned(FOnClose) then FOnClose(Self);
  Free;
end;

procedure TMainForm.CloseTabeProc(Sender: TObject);
begin
  ShowMessage(''close'');
end;

procedure TMainForm.FormCreate(Sender: TObject);
var I: Integer;
    NT:TCloseTabSheet;
begin
  PageControlCloseButton.TabWidth := 150;
  PageControlCloseButton.OwnerDraw := True;
  NT:=TCloseTabSheet.Create(PageControlCloseButton);
  NT.Caption:=''TabSheet4'';
  NT.PageControl:=PageControlCloseButton;
  NT.OnClose:=CloseTabeProc;

  FCloseButtonMouseDownTab := nil;
end;

procedure TMainForm.PageControlCloseButtonDrawTab(Control: TCustomTabControl;
  TabIndex: Integer; const Rect: TRect; Active: Boolean);
var
  CloseBtnSize: Integer;
  PageControl: TPageControl;
  TabSheet:TCloseTabSheet;
  TabCaption: TPoint;
  CloseBtnRect: TRect;
  CloseBtnDrawState: Cardinal;
  CloseBtnDrawDetails: TThemedElementDetails;
begin
  PageControl := Control as TPageControl;
  TabCaption.Y := Rect.Top + 3;

  if Active then
  begin
    CloseBtnRect.Top := Rect.Top + 4;
    CloseBtnRect.Right := Rect.Right - 5;
    TabCaption.X := Rect.Left + 6;
  end
  else
  begin
    CloseBtnRect.Top := Rect.Top + 3;
    CloseBtnRect.Right := Rect.Right - 5;
    TabCaption.X := Rect.Left + 3;
  end;
  if PageControl.Pages[TabIndex] is TCloseTabSheet then
  begin
    TabSheet:=PageControl.Pages[TabIndex] as TCloseTabSheet;
    CloseBtnSize := 14;

    CloseBtnRect.Bottom := CloseBtnRect.Top + CloseBtnSize;
    CloseBtnRect.Left := CloseBtnRect.Right - CloseBtnSize;
    TabSheet.FCloseButtonRect := CloseBtnRect;

    PageControl.Canvas.FillRect(Rect);
    PageControl.Canvas.TextOut(TabCaption.X, TabCaption.Y,
            PageControl.Pages[TabIndex].Caption);

    if not ThemeServices.ThemesEnabled then
    begin
      if (FCloseButtonMouseDownTab = TabSheet) and FCloseButtonShowPushed then
        CloseBtnDrawState := DFCS_CAPTIONCLOSE + DFCS_PUSHED
      else
        CloseBtnDrawState := DFCS_CAPTIONCLOSE;

      Windows.DrawFrameControl(PageControl.Canvas.Handle,
        TabSheet.FCloseButtonRect, DFC_CAPTION, CloseBtnDrawState);
    end
    else
    begin
      Dec(TabSheet.FCloseButtonRect.Left);

      if (FCloseButtonMouseDownTab = TabSheet) and FCloseButtonShowPushed then
        CloseBtnDrawDetails := ThemeServices.GetElementDetails(twCloseButtonPushed)
      else
        CloseBtnDrawDetails := ThemeServices.GetElementDetails(twCloseButtonNormal);

      ThemeServices.DrawElement(PageControl.Canvas.Handle, CloseBtnDrawDetails,
                TabSheet.FCloseButtonRect);
    end;
  end else begin
    PageControl.Canvas.FillRect(Rect);
    PageControl.Canvas.TextOut(TabCaption.X, TabCaption.Y,
                 PageControl.Pages[TabIndex].Caption);
  end;
end;

procedure TMainForm.PageControlCloseButtonMouseDown(Sender: TObject;
  Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
  I: Integer;
  PageControl: TPageControl;
  TabSheet:TCloseTabSheet;
begin
  PageControl := Sender as TPageControl;

  if Button = mbLeft then
  begin
    for I := 0 to PageControl.PageCount - 1 do
    begin
      if not (PageControl.Pages[i] is TCloseTabSheet) then Continue;
      TabSheet:=PageControl.Pages[i] as TCloseTabSheet;
      if PtInRect(TabSheet.FCloseButtonRect, Point(X, Y)) then
      begin
        FCloseButtonMouseDownTab := TabSheet;
        FCloseButtonShowPushed := True;
        PageControl.Repaint;
      end;
    end;
  end;
end;

procedure TMainForm.PageControlCloseButtonMouseLeave(Sender: TObject);
var
  PageControl: TPageControl;
begin
  PageControl := Sender as TPageControl;
  FCloseButtonShowPushed := False;
  PageControl.Repaint;
end;

procedure TMainForm.PageControlCloseButtonMouseMove(Sender: TObject;
  Shift: TShiftState; X, Y: Integer);
var
  PageControl: TPageControl;
  Inside: Boolean;
begin
  PageControl := Sender as TPageControl;

  if (ssLeft in Shift) and Assigned(FCloseButtonMouseDownTab) then
  begin
    Inside := PtInRect(FCloseButtonMouseDownTab.FCloseButtonRect, Point(X, Y));

    if FCloseButtonShowPushed <> Inside then
    begin
      FCloseButtonShowPushed := Inside;
      PageControl.Repaint;
    end;
  end;
end;

procedure TMainForm.PageControlCloseButtonMouseUp(Sender: TObject;
  Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
  PageControl: TPageControl;
begin
  PageControl := Sender as TPageControl;

  if (Button = mbLeft) and Assigned(FCloseButtonMouseDownTab) then
  begin
    if PtInRect(FCloseButtonMouseDownTab.FCloseButtonRect, Point(X, Y)) then
    begin
      FCloseButtonMouseDownTab.DoClose;
      FCloseButtonMouseDownTab := nil;
      PageControl.Repaint;
    end;
  end;
end;

end.