我有这个delphi 2010代码:
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, Math, ExtCtrls, pngimage;
type
TMyHintWindow = class(THintWindow)
private
FBitmap : TBitmap;
ThePNG : TPngImage;
FRegion : THandle;
procedure FreeRegion;
protected
procedure CreateParams(var Params : TCreateParams); override;
procedure Paint; override;
procedure Erase(var Message : TMessage); message WM_ERASEBKGND;
public
constructor Create(AOwner : TComponent); override;
destructor Destroy; override;
procedure ActivateHint(Rect : TRect; const AHint : String); Override;
end;
type
TForm1 = class(TForm)
Button1: TButton;
procedure FormCreate(Sender : TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1 : TForm1;
implementation
{$R *.dfm}
// --------------------------------------------------------------------------- //
constructor TMyHintWindow.Create(AOwner : TComponent);
begin
inherited Create(AOwner);
FBitmap := TBitmap.Create;
FBitmap.PixelFormat := pf32bit;
FBitmap.HandleType := bmDIB;
FBitmap.Transparent := True;
FBitmap.TransparentMode := tmAuto; // }tmFixed;
FBitmap.TransparentColor := clWhite;
FBitmap.AlphaFormat := {afPremultiplied; // }afDefined;
ThePNG := TPngImage.Create;
ThePNG.Transparent := True;
ThePNG.TransparentColor := clWhite;
ThePNG.LoadFromFile('D:\project-1\tooltip.png');
FBitmap.LoadFromFile('D:\project-1\tooltip.bmp');
end;
// --------------------------------------------------------------------------- //
destructor TMyHintWindow.Destroy;
begin
FBitmap.Free;
FreeRegion;
inherited;
end;
// --------------------------------------------------------------------------- //
procedure TMyHintWindow.CreateParams(var Params : TCreateParams);
const
CS_DROPSHADOW = $20000;
begin
inherited;
Params.Style := Params.Style - WS_BORDER;
Params.WindowClass.Style := Params.WindowClass.Style or CS_DROPSHADOW;
end;
// --------------------------------------------------------------------------- //
procedure TMyHintWindow.FreeRegion;
begin
if FRegion <> 0 then
begin
SetWindowRgn(Handle, 0, True);
DeleteObject(FRegion);
FRegion := 0;
end;
end;
// --------------------------------------------------------------------------- //
procedure TMyHintWindow.ActivateHint(Rect : TRect; const AHint : String);
var
i : Integer;
begin
Caption := AHint;
Canvas.Font := Screen.HintFont;
FBitmap.Canvas.Font := Screen.HintFont;
DrawText(Canvas.Handle, PChar(Caption), Length(Caption), Rect, DT_CALCRECT or DT_NOPREFIX);
Width := 230; // (Rect.Right - Rect.Left) + 16;
Height := 61; // (Rect.Bottom - Rect.Top) + 10;
FBitmap.Width := Width;
FBitmap.Height := Height;
Left := Rect.Left;
Top := Rect.Top;
FreeRegion;
with Rect do
FRegion := CreateRoundRectRgn(1, 1, Width, Height, 3, 3);
if FRegion <> 0 then
SetWindowRgn(Handle, FRegion, True);
AnimateWindowProc(Handle, 300, AW_BLEND);
SetWindowPos(Handle, HWND_TOPMOST, Left, Top, 0, 0, SWP_SHOWWINDOW or SWP_NOACTIVATE or SWP_NOSIZE);
end;
// --------------------------------------------------------------------------- //
procedure TMyHintWindow.Paint;
var
CaptionRect : TRect;
begin
with FBitmap.Canvas do
begin
Font.Color := clWindowText;
Brush.Style := bsClear;
end; // with
CaptionRect := Rect(25, 26, Width - 10, Height - 10);
SetBkMode(Canvas.Handle, TRANSPARENT);
DrawText(FBitmap.Canvas.Handle, PChar(Caption), Length(Caption), CaptionRect, DT_WORDBREAK OR DT_NOPREFIX);
BitBlt(Canvas.Handle, 0, 0, Width, Height, FBitmap.Canvas.Handle, 0, 0, SRCERASE{SRCCOPY});
end;
// --------------------------------------------------------------------------- //
procedure TMyHintWindow.Erase(var Message : TMessage);
begin
Message.Result := 0;
end;
// --------------------------------------------------------------------------- //
procedure TForm1.FormCreate(Sender : TObject);
begin
HintWindowClass := TMyHintWindow;
Button1.Hint := 'This is a nice fake tooltip!';
end;
// --------------------------------------------------------------------------- //
end.
这个例子有两个问题:
我需要用透明边框绘制 PNG。图片本身在这里
如果您运行这个项目(表单只有一个名为 Button1 的按钮),并显示几次提示,您应该意识到每次显示提示时标题都会变粗。我很确定我忘记了忘记清除/擦除的背景,但我不知道如何解决这个问题。
有人可以告诉我如何解决这两个问题吗?