我需要制作一个程序,其中包含一个具有透明区域的PNG图像的表单。表单必须是不可见的,而图像必须保持可见,并且透明区域必须保持透明。问题在于图像的透明度。在这种情况下,主表单是透明的、不可见的,而所有组件/控件都是可见的。但是,PNG图像的透明区域不保持透明。如何保持透明度?
procedure MakeTransparent;
var
AControl: TControl;
A, Margin, X, Y, CtlX, CtlY: Integer;
begin
Margin := (Width - ClientWidth) div 2;
FullRgn := CreateRectRgn(0, 0, Width, Height);
X := Margin;
Y := Height - ClientHeight - Margin;
ClientRgn := CreateRectRgn(X, Y, X + ClientWidth, Y + ClientHeight);
CombineRgn(FullRgn, FullRgn, ClientRgn, RGN_DIFF);
for A := 0 to ControlCount - 1 do
begin
AControl := Controls[A];
if (AControl is TWinControl) or (AControl is TGraphicControl) then with AControl do
begin
if Visible then
begin
CtlX := X + Left;
CtlY := Y + Top;
CtlRgn := CreateRectRgn(CtlX, CtlY, CtlX + Width, CtlY + Height);
CombineRgn(FullRgn, FullRgn, CtlRgn, RGN_OR);
end;
end;
end;
SetWindowRgn(Handle, FullRgn, True);
end;
procedure UndoTransparency;
begin
FullRgn := CreateRectRgn(0, 0, Width, Height);
CombineRgn(FullRgn, FullRgn, FullRgn, RGN_COPY);
SetWindowRgn(Handle, FullRgn, True);
end;
Color
、TransparentColor
和TransparentColorValue
属性,然后将png加载到TImage
中即可完成! - Sertac Akyuz