我有下面着段程序,我单步执行到第二行就报错“Abstract Error”,请问我错在哪呢???
procedure TForm1.Button1Click(Sender: TObject);
var TempGraphic:TGraphic;
begin
TempGraphic:=TGraphic.Create;
TempGraphic.LoadFromFile('testimg.jpg');
........
end;
procedure TForm1.Button1Click(Sender: TObject);
var TempGraphic:TGraphic;
begin
TempGraphic:=TGraphic.Create;
TempGraphic.LoadFromFile('testimg.jpg');
........
end;
你要先继承他,他重新定义他的抽象过程。例如
procedure SetHeight(Value: Integer); virtual; abstract;你要继承TGraphic类,在自己的类中为SetHeight写如代码.
procedure TForm1.Button1Click(Sender: TObject);
var Temppic:Tpicture;
begin
//form2.show;
TempPic:=Tpicture.Create;
Temppic.LoadFromFile('20030326.bmp');
with self.canvas do
begin
Draw(0,0,Temppic.Graphic);
end;end;果然图象能够正确显示,不过出现了新的问题,我发现当舱口大小发生改变时,显示在舱口上的图片就不见了,这是怎么回事,怎样才能让图片正确显示呢?