procedure TEdit.RepaintWindow; var DC: hDC; TmpBitmap, Bitmap: hBitmap; begin if FTransparent then begin FPainting := true; HideCaret(Handle); DC := CreateCompatibleDC(GetDC(Handle)); TmpBitmap := CreateCompatibleBitmap(GetDC(Handle), Succ(ClientWidth), Succ(ClientHeight)); Bitmap := SelectObject(DC, TmpBitmap); PaintTo(DC, 0, 0); BitBlt(GetDC(Handle), BorderRec[BorderStyle], BorderRec[BorderStyle], ClientWidth, ClientHeight, DC, 1, 1, SRCCOPY); SelectObject(DC, Bitmap); DeleteDC(DC); ReleaseDC(Handle, GetDC(Handle)); DeleteObject(TmpBitmap); ShowCaret(Handle); FPainting := false; end; end; procedure TEdit.SetAlignText(Value: TAlignment); begin if FAlignText <> Value then begin FAlignText := Value; RecreateWnd; Invalidate; end; end;procedure TEdit.SetParent(AParent: TWinControl); begin inherited SetParent(AParent); end;procedure TEdit.SetTransparent(Value: Boolean); begin if FTransparent <> Value then begin FTransparent := Value; Invalidate; end; end;procedure TEdit.WMEraseBkGnd(var Message: TWMEraseBkGnd); var DC: hDC; i: integer; p: TPoint; begin if FTransparent then begin if Assigned(Parent) then begin DC := Message.DC; i := SaveDC(DC); p := GetScreenClient(self); p.x := -p.x; p.y := -p.y; MoveWindowOrg(DC, p.x, p.y); SendMessage(Parent.Handle, $0014, DC, 0); TCtrl(Parent).PaintControls(DC, nil); RestoreDC(DC, i); end; end else inherited; end;procedure TEdit.WMMove(var Message: TWMMove); begin inherited; Invalidate; end;procedure TEdit.WMNCPaint(var Message: TMessage); begin inherited; end;procedure TEdit.WMPaint(var Message: TWMPaint); begin inherited; if FTransparent then if not FPainting then RepaintWindow; end;procedure TEdit.WMSize(var Message: TWMSize); begin inherited; Invalidate; end;
edit没有canvas的
期待高手
upup...
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, jpeg, ExtCtrls, StdCtrls, Mask, RzEdit;type
TCtrl = class(TWinControl);
TEdit = class(StdCtrls.TEdit)
private
FAlignText: TAlignment;
FTransparent: Boolean;
FPainting: Boolean;
procedure SetAlignText(Value: TAlignment);
procedure SetTransparent(Value: Boolean);
procedure WMPaint(var Message: TWMPaint); message WM_PAINT;
procedure WMNCPaint (var Message: TMessage); message WM_NCPAINT;
procedure WMEraseBkGnd(var Message: TWMEraseBkGnd); message WM_ERASEBKGND;
procedure CNCtlColorEdit(var Message: TWMCtlColorEdit); message CN_CTLCOLOREDIT;
procedure CNCtlColorStatic(var Message: TWMCtlColorStatic); message CN_CTLCOLORSTATIC;
procedure CMParentColorChanged(var Message: TMessage); message CM_PARENTCOLORCHANGED;
procedure WMSize(var Message: TWMSize); message WM_SIZE;
procedure WMMove(var Message: TWMMove); message WM_MOVE;
protected
procedure RepaintWindow;
procedure CreateParams(var Params: TCreateParams); override;
procedure Change; override;
procedure SetParent(AParent: TWinControl); override;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
published
property AlignText: TAlignment read FAlignText write SetAlignText default taLeftJustify;
property Transparent: Boolean read FTransparent write SetTransparent default false;
end;
TMemo = class(StdCtrls.TMemo)
private
FAlignText: TAlignment;
FTransparent: Boolean;
FPainting: Boolean;
procedure SetAlignText(Value: TAlignment);
procedure SetTransparent(Value: Boolean);
procedure WMPaint(var Message: TWMPaint); message WM_PAINT;
procedure WMNCPaint (var Message: TMessage); message WM_NCPAINT;
procedure WMEraseBkGnd(var Message: TWMEraseBkGnd); message WM_ERASEBKGND;
procedure CNCtlColorEdit(var Message: TWMCtlColorEdit); message CN_CTLCOLOREDIT;
procedure CNCtlColorStatic(var Message: TWMCtlColorStatic); message CN_CTLCOLORSTATIC;
procedure CMParentColorChanged(var Message: TMessage); message CM_PARENTCOLORCHANGED;
procedure WMSize(var Message: TWMSize); message WM_SIZE;
procedure WMMove(var Message: TWMMove); message WM_MOVE;
protected
procedure RepaintWindow;
procedure CreateParams(var Params: TCreateParams); override;
procedure Change; override;
procedure SetParent(AParent: TWinControl); override;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
published
property AlignText: TAlignment read FAlignText write SetAlignText default taLeftJustify;
property Transparent: Boolean read FTransparent write SetTransparent default false;
end;
TForm1 = class(TForm)
Image1: TImage;
Edit1: TEdit;
Edit2: TEdit;
private
{ Private declarations }
public
{ Public declarations }
end;var
Form1: TForm1;implementation{$R *.dfm}const
BorderRec: array[TBorderStyle] of Integer = (1, -1);function GetScreenClient(Control: TControl): TPoint;
var
p: TPoint;
begin
p := Control.ClientOrigin;
ScreenToClient(Control.Parent.Handle, p);
Result := p;
end;{ TEdit }procedure TEdit.Change;
begin
RepaintWindow;
inherited Change;
end;procedure TEdit.CMParentColorChanged(var Message: TMessage);
begin
inherited;
if FTransparent then
Invalidate;
end;procedure TEdit.CNCtlColorEdit(var Message: TWMCtlColorEdit);
begin
inherited;
if FTransparent then
SetBkMode(Message.ChildDC, 1);
end;procedure TEdit.CNCtlColorStatic(var Message: TWMCtlColorStatic);
begin
inherited;
if FTransparent then
SetBkMode(Message.ChildDC, 1);
end;constructor TEdit.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
FAlignText := taLeftJustify;
FTransparent := True;
FPainting := False;
BorderStyle := bsNone;
Font.Color := clRed;
Font.Style := Font.Style + [fsBold];
//Self.Align := alTop;
end;procedure TEdit.CreateParams(var Params: TCreateParams);
const
Alignments: array [TAlignment] of DWord = (ES_LEFT, ES_RIGHT, ES_CENTER);
begin
inherited CreateParams(Params);
Params.Style := Params.Style or ES_MULTILINE or Alignments[FAlignText];
end;destructor TEdit.Destroy;
begin
inherited Destroy;
end;
var
DC: hDC;
TmpBitmap, Bitmap: hBitmap;
begin
if FTransparent then
begin
FPainting := true;
HideCaret(Handle);
DC := CreateCompatibleDC(GetDC(Handle));
TmpBitmap := CreateCompatibleBitmap(GetDC(Handle), Succ(ClientWidth), Succ(ClientHeight));
Bitmap := SelectObject(DC, TmpBitmap);
PaintTo(DC, 0, 0);
BitBlt(GetDC(Handle), BorderRec[BorderStyle], BorderRec[BorderStyle], ClientWidth, ClientHeight, DC, 1, 1, SRCCOPY);
SelectObject(DC, Bitmap);
DeleteDC(DC);
ReleaseDC(Handle, GetDC(Handle));
DeleteObject(TmpBitmap);
ShowCaret(Handle);
FPainting := false;
end;
end;
procedure TEdit.SetAlignText(Value: TAlignment);
begin
if FAlignText <> Value then
begin
FAlignText := Value;
RecreateWnd;
Invalidate;
end;
end;procedure TEdit.SetParent(AParent: TWinControl);
begin
inherited SetParent(AParent);
end;procedure TEdit.SetTransparent(Value: Boolean);
begin
if FTransparent <> Value then
begin
FTransparent := Value;
Invalidate;
end;
end;procedure TEdit.WMEraseBkGnd(var Message: TWMEraseBkGnd);
var
DC: hDC;
i: integer;
p: TPoint;
begin
if FTransparent then
begin
if Assigned(Parent) then
begin
DC := Message.DC;
i := SaveDC(DC);
p := GetScreenClient(self);
p.x := -p.x;
p.y := -p.y;
MoveWindowOrg(DC, p.x, p.y);
SendMessage(Parent.Handle, $0014, DC, 0);
TCtrl(Parent).PaintControls(DC, nil);
RestoreDC(DC, i);
end;
end else inherited;
end;procedure TEdit.WMMove(var Message: TWMMove);
begin
inherited;
Invalidate;
end;procedure TEdit.WMNCPaint(var Message: TMessage);
begin
inherited;
end;procedure TEdit.WMPaint(var Message: TWMPaint);
begin
inherited;
if FTransparent then
if not FPainting then
RepaintWindow;
end;procedure TEdit.WMSize(var Message: TWMSize);
begin
inherited;
Invalidate;
end;
把uses里的rzedit去掉,里面没用到。在当前窗体中加如的任何edit,都为透明的了!