如何在TEdit中画TComboBox上右边的那个下拉小按钮

回复于： 2004-07-22 21:50:55

给你专门写了个，怎么样？

unit myedit;

 

interface

 

uses

  Windows, SysUtils, Classes, ComCtrls,forms,Controls, ExtCtrls,StdCtrls,Buttons,Graphics;

 

type

 TMyButton = class(TSpeedbutton)

 private

 protected

  procedure Paint; override;

 public

 end;

 

  TMyEdit = class(TCustomEdit)

  private

 

  protected

  published

    property Anchors;

    property AutoSelect;

    property AutoSize;

    property BevelEdges;

    property BevelInner;

    property BevelKind default bkNone;

    property BevelOuter;

    property BiDiMode;

    property BorderStyle;

    property CharCase;

    property Color;

    property Constraints;

    property Ctl3D;

    property DragCursor;

    property DragKind;

    property DragMode;

    property Enabled;

    property Font;

    property HideSelection;

    property ImeMode;

    property ImeName;

    property MaxLength;

    property OEMConvert;

    property ParentBiDiMode;

    property ParentColor;

    property ParentCtl3D;

    property ParentFont;

    property ParentShowHint;

    property PasswordChar;

    //property PopupMenu;

    property ReadOnly;

    property ShowHint;

    property TabOrder;

    property TabStop;

    //property Text;

    property Visible;

    //property OnChange;

    //property OnClick;

    //property OnContextPopup;

    //property OnDblClick;

    //property OnDragDrop;

    //property OnDragOver;

    //property OnEndDock;

    //property OnEndDrag;

    //property OnEnter;

    //property OnExit;

    //property OnKeyDown;

    //property OnKeyPress;

    //property OnKeyUp;

    //property OnMouseDown;

    //property OnMouseMove;

    //property OnMouseUp;

    //property OnStartDock;

    //property OnStartDrag;

  end;

 

 

 

type

  TNewPanel = class(TCustomPanel)

  private

    FEdit: TMyEdit;

    FButton: TMyButton;

  protected

    procedure Resize; override;

  public

    constructor Create(AOwner: TComponent); override;

    destructor Destroy; override;

  published

    property Edit: TMyEdit read FEdit;

    property UpDown: TMyButton read FButton;

    property BevelOuter default bvNone;

    property BorderStyle default bsSingle;

    property Width default 80;

    property Height default 20;

  end;

 

procedure Register;

 

implementation

 

procedure Register;

begin

  RegisterComponents('Mycomponent', [TNewPanel]);

end;

 

{ TMyPanel }

 

constructor TNewPanel.Create(AOwner: TComponent);

begin

  inherited;

  Caption := '';

  BevelOuter := bvNone;

  BorderStyle := bsSingle;

 

  FEdit := TMyEdit.Create(Self);

  FEdit.SetSubComponent(True);

  FEdit.BorderStyle := bsNone;

  FEdit.Height := 16;

  FEdit.Parent := Self;

 

 

  Fbutton := TMyButton.Create(Self);

  FButton.Name:='button';

  Fbutton.SetSubComponent(True);

  FButton.Parent := Self;

  Fbutton.Height:=16;

  Fbutton.Width:=16;

  Width := 80;

  Height := 20;

end;

 

destructor TNewPanel.Destroy;

begin

  FEdit.Free;

  FButton.Free;

  inherited;

end;

 

procedure TNewPanel.Resize;

begin

  inherited;

  FEdit.Width :=self.Width-20;

  FButton.Left:=FEdit.Left+Fedit.Width;

 

  Fedit.Height:=self.Height-4;

  fButton.Height:=Fedit.Height;

end;

 

 

 

 

{ TMyButton }

 

procedure TMyButton.Paint;

var

x,y:integer;

begin

  inherited;

  x:=5;

  y:=(self.Height-3) div 2;

  canvas.Pen.Color:=Clblack;

  Canvas.MoveTo(X, Y);

  canvas.lineTo(X+7,y);

 

  Canvas.MoveTo(X+1,y+1);

  Canvas.LineTo(X + 6, Y+1);

 

  Canvas.MoveTo(X + 2, Y + 2);

  Canvas.LineTo(X + 5, Y+2);

 

  Canvas.MoveTo(X + 3, Y + 3);

  Canvas.LineTo(X + 4, Y+3);

end;

 

end.

 

======================

回复于： 2004-07-23 09:29:27

procedure TForm1.Button1Click(Sender: TObject);

var

  H: THandle;

  R: TRect;

begin

  H := GetDC(Edit1.Handle);

  R := Edit1.ClientRect;

  R.Left := R.Right - 20;

  DrawFrameControl(H, R, DFC_SCROLL,

                   DFCS_SCROLLCOMBOBOX);

  ReleaseDC(Edit1.Handle, H);

end;