Delphi GDI+ 桌面歌词
新建一个应用程序，在窗体上放置一个TTimer和一个TPopupMenu，TTimer的Interval属性为1500，TPopupMenu建立三个子菜单项，分别为“总在最前”、“背景穿透”和“退出”。
再准备一张背景图片。工程源代码如下：unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, IGDIPlus, ExtCtrls, Menus; type TForm1 = class(TForm) tmr1: TTimer; pm1: TPopupMenu; mni_topMost: TMenuItem; mni_transparent: TMenuItem; mni_exit: TMenuItem; procedure FormCreate(Sender: TObject); procedure FormMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer); procedure FormMouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer); procedure tmr1Timer(Sender: TObject); procedure mni_topMostClick(Sender: TObject); procedure MouseLeave(var Msg: TMessage);message WM_MOUSELEAVE; procedure mni_transparentClick(Sender: TObject); procedure mni_exitClick(Sender: TObject); private m_Kind: Integer; //当前第几行字符串 m_bBack: Boolean; //是否显示背景 m_pszbuf: array[0..5] of WideString; //要绘制的字符串数组 function UpdateDisplay(pszbuf: WideString;bBack: Boolean = False; Transparent: Integer = 100):Boolean; public { Public declarations } end; var Form1: TForm1; implementation {$R *.dfm} {------------------------------------------- 过程名: TForm1.UpdateDisplay 功能: 绘制桌面歌词 参数: pszbuf: WideString; 绘制的字符串 bBack: Boolean; 是否绘制背景 Transparent: Integer 透明程度 返回值: Boolean -------------------------------------------} function TForm1.UpdateDisplay(pszbuf: WideString;bBack: Boolean;Transparent: Integer):Boolean; var hdcTemp,hdcScreen,m_hdcMemory: HDC; hBitMap: Windows.HBITMAP; blend: BLENDFUNCTION; //这种结构的混合控制通过指定源和目标位图的混合功能 rct: TRect; ptWinPos,ptSrc: TPoint; graphics: IGPGraphics; //封装一个 GDI+ 绘图图面 fontFamily: IGPFontFamily; //定义有着相似的基本设计但在形式上有某些差异的一组字样 path: IGPGraphicsPath; //表示一系列相互连接的直线和曲线 strFormat: IGPStringFormat;//封装文本布局信息，显示操作 pen,pen1,pen2: IGPPen; //定义用于绘制直线和曲线的对象 linGrBrush,linGrBrushW: IGPLinearGradientBrush; //使用线性渐变封装 Brush brush: IGPSolidBrush; //定义单色画笔，画笔用于填充图形形状 image: TGPImage; //使用这个类来创建和操作GDI+图像 i: Integer; sizeWindow: SIZE; begin //---------------------开始：初始化操作-------------------------------------- hdcTemp := GetDC(Self.Handle); m_hdcMemory := CreateCompatibleDC(hdcTemp); hBitMap := CreateCompatibleBitmap(hdcTemp,755,350); SelectObject(m_hdcMemory,hBitMap); if (Transparent < 0) or (Transparent > 100) then Transparent := 100; with blend do begin BlendOp := AC_SRC_OVER; //把源图片覆盖到目标之上 BlendFlags := 0; AlphaFormat := AC_SRC_ALPHA;//每个像素有各自的alpha通道 SourceConstantAlpha :=Trunc(Transparent * 2.55); //源图片的透明度 end; hdcScreen := GetDC(Self.Handle); GetWindowRect(Self.Handle,rct); ptWinPos := Point(rct.Left,rct.Top); graphics := TGPGraphics.Create(m_hdcMemory); graphics.SetSmoothingMode(SmoothingModeAntiAlias); //指定平滑（抗锯齿） graphics.SetInterpolationMode(InterpolationModeHighQualityBicubic);//指定的高品质，双三次插值 fontFamily := TGPFontFamily.Create('微软雅黑'); //△字体，效果图为'微软雅黑'字体 strFormat := TGPStringFormat.Create(); path := TGPGraphicsPath.Create(); //---------------------结束：初始化操作-------------------------------------- path.AddString(pszbuf, //要添加的 String fontFamily, //表示绘制文本所用字体的名称 0, //指定应用到文本的字形信息,这里为普通文本 38, //限定字符的 Em（字体大小）方框的高度 MakePoint(10,10), //一个 Point，它表示文本从其起始的点 strFormat); //指定文本格式设置信息 pen := TGPPen.Create(MakeColor(155,215,215,215),3); //颜色、宽度 graphics.DrawPath(pen,path); //初步绘制GraphicsPath linGrBrush := TGPLinearGradientBrush.Create(MakePoint(0,0), //线性渐变起始点 MakePoint(0,90), //线性渐变终结点 MakeColor(255,255,255,255), //线性渐变起始色 MakeColor(255,30,120,195)); //线性渐变结束色 linGrBrushW := TGPLinearGradientBrush.Create(MakePoint(0,10), MakePoint(0,60), MakeColor(255,255,255,255), MakeColor(15,1,1,1)); //---------------------开始：画字符串阴影-------------------------------------- for i := 1 to 8 do begin pen.SetWidth(i); pen.SetColor(MakeColor(62, 0, 2, 2)); pen.SetLineJoin(LineJoinRound); //指定圆形联接。这将在两条线之间产生平滑的圆弧。 graphics.DrawPath(pen,path); end; //---------------------开始：画背景框和背景图---------------------------------- if bBack then begin brush := TGPSolidBrush.Create(MakeColor(25,228,228,228)); pen1 := TGPPen.Create(MakeColor(155,223,223,223)); pen2 := TGPPen.Create(MakeColor(55,223,223,223)); image := TGPImage.Create('back.png'); //背景图片 graphics.FillRectangle(brush,3,5,750,90); //填充背景框色 graphics.DrawRectangle(pen1,2,6,751,91); //内层背景框 graphics.DrawRectangle(pen2,1,5,753,93); //外层背景框 graphics.DrawImage(image,600,25); end; //---------------------开始：以渐变色笔刷填充GraphicsPath内部----------------- graphics.FillPath(linGrBrush,path); graphics.FillPath(linGrBrushW,path); sizeWindow.cx := 755; sizeWindow.cy := 350; ptSrc := Point(0,0); //---------------------开始：更新一个分层的窗口的位置，大小，形状，内容和半透明度--- Result := UpdateLayeredWindow(Self.Handle, //分层窗口的句柄 hdcScreen, //屏幕的DC句柄 @ptWinPos, //分层窗口新的屏幕坐标 @sizeWindow, //分层窗口新的大小 m_hdcMemory, //用来定义分层窗口的表面DC句柄 @ptSrc, //分层窗口在设备上下文的位置 0, //合成分层窗口时使用指定颜色键值 @blend, //在分层窗口进行组合时的透明度值 ULW_ALPHA); //使用pblend为混合功能 //---------------------开始：释放和删除-------------------------------------- ReleaseDC(Self.Handle,hdcScreen); ReleaseDC(Self.Handle,hdcTemp); DeleteObject(hBitMap); DeleteDC(m_hdcMemory); end; {------------------------------------------- 功能: 窗体创建初始化 -------------------------------------------} procedure TForm1.FormCreate(Sender: TObject); begin //设置窗体属性 SetWindowLong(Application.Handle, GWL_EXSTYLE, GetWindowLong(Application.Handle,GWL_EXSTYLE) or WS_EX_TOOLWINDOW); //不在任务栏出现 SetWindowLong(Self.Handle, GWL_EXSTYLE, GetWindowLong(Self.Handle,GWL_EXSTYLE) or WS_EX_LAYERED //层次窗口 or WS_EX_TOOLWINDOW); //不在alt+tab中出现 //初始化变量等等 m_kind := 0; m_bBack := False; PopupMenu := pm1; Self.Cursor := crHandPoint; mni_topMost.Checked := True; mni_topMostClick(mni_topMost); m_pszbuf[0] := '你好 Everyone!'; m_pszbuf[1] := '这是GDI+绘制的桌面歌词!'; m_pszbuf[2] := '欢迎光临无幻博客!'; m_pszbuf[3] := 'http://blog.csdn.net/akof1314!'; m_pszbuf[4] := '源码根据需要进行修改!'; UpdateDisplay(m_pszbuf[m_kind],m_bBack); end; {------------------------------------------- 功能: 鼠标按下移动窗体 -------------------------------------------} procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer); begin ReleaseCapture; SendMessage(Self.Handle,WM_SYSCOMMAND,SC_MOVE or HTCAPTION,0); end; {------------------------------------------- 功能: 鼠标移过窗体 -------------------------------------------} procedure TForm1.FormMouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer); var xh: TTrackMouseEvent; begin m_bBack := True; UpdateDisplay(m_pszbuf[m_kind],m_bBack); with xh do begin cbSize := SizeOf(xh); dwFlags := TME_LEAVE; hwndTrack := Self.Handle; dwHoverTime := 0; end; TrackMouseEvent(xh); end; {------------------------------------------- 功能: 鼠标移出窗体时，去掉背景 -------------------------------------------} procedure TForm1.MouseLeave(var Msg: TMessage); begin m_bBack := False; UpdateDisplay(m_pszbuf[m_kind],m_bBack); Msg.Result := 0; end; {------------------------------------------- 功能: 定时器切换字符串 -------------------------------------------} procedure TForm1.tmr1Timer(Sender: TObject); begin Inc(m_Kind); if m_kind > 4 then m_kind := 0; UpdateDisplay(m_pszbuf[m_kind],m_bBack); end; {------------------------------------------- 功能: 窗体置顶 -------------------------------------------} procedure TForm1.mni_topMostClick(Sender: TObject); begin if mni_topMost.Checked then SetWindowPos(Self.Handle, HWND_TOPMOST, 0,0,0,0, SWP_NOSIZE or SWP_NOMOVE) //窗口置顶 else SetWindowPos(Self.Handle, HWND_NOTOPMOST, 0,0,0,0, SWP_NOSIZE or SWP_NOMOVE); //窗口置顶 end; {------------------------------------------- 功能: 背景穿透 （相当于锁定桌面） -------------------------------------------} procedure TForm1.mni_transparentClick(Sender: TObject); begin SetWindowLong(Self.Handle, GWL_EXSTYLE, GetWindowLong(Self.Handle,GWL_EXSTYLE) or WS_EX_TRANSPARENT); Application.MessageBox('你已关闭不了程序了，请从任务管理器里关闭', '提示',MB_OK or MB_ICONINFORMATION); end; {------------------------------------------- 功能: 退出 -------------------------------------------} procedure TForm1.mni_exitClick(Sender: TObject); begin Self.Close; end;