Delphi 4错误: - 不兼容的类型:"TBitmap"和"TObject"

Question

在我尝试运行/编译/构建Proiject时出现此错误

       Incompatible Types : “TBitmap” and “TObject”

光标指向 Bitmap := FSectionList.BackgroundBitmap

请帮我搞清楚.这里像一辆交通拥挤的救护车

以下是代码的一部分: -

procedure ThtmlViewer.DoBackground1(ACanvas: TCanvas; ATop, AWidth, AHeight, FullHeight: integer);
var
  ARect: TRect;
  Bitmap, Mask: TBitmap;
  PRec: PtPositionRec;
  BW, BH, X, Y, X2, Y2, IW, IH, XOff, YOff: integer;
  Fixed: boolean;

begin
ARect := Rect(0, 0, AWidth, AHeight);
Bitmap := FSectionList.BackgroundBitmap;    
if FSectionList.ShowImages and Assigned(Bitmap) then
  begin
  Mask := FSectionList.BackgroundMask;
  BW := Bitmap.Width;
  BH := Bitmap.Height;
  PRec := FSectionList.BackgroundPRec;
  Fixed := PRec[1].Fixed;
  if Fixed then
    begin  {fixed background}
    XOff := 0;
    YOff := 0;
    IW := AWidth;
    IH := AHeight;
    end
  else
    begin   {scrolling background}
    XOff := 0;
    YOff := ATop;
    IW := AWidth;
    IH := FullHeight;
    end;
  CalcBckgrndLoctionAndTilng(PRec, ARect, XOff, YOff, IW, IH, BW, BH, X, Y, X2, Y2);

  DrwBckgrnd(ACanvas, ARect, X, Y, X2, Y2, Bitmap, Mask, BW, BH, PaintPanel.Color);
  end
else
  begin  {no background image, show color only}
  DrwBckgrnd(ACanvas, ARect, 0,0,0,0, Nil, Nil, 0, 0, PaintPanel.Color);
  end;
end;

谢谢和关心Vas

Answer 1

我只是猜测,但是从错误消息和FSectionList的名称来看,它是某种List,它包含通用的TObject实例,而BackgroundBitmap就是其中之一.

您需要将其强制转换为TBitmap:

Bitmap := FSectionList.BackgroundBitmap as TBitMap;