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az@hyliosoft.com · Guest

Hi everyone,

I'm using D7 and I've created a control that derives a TCustomControl.
I'm painting the new control with a bitmap by using the canvas's
control.

I need to put a toolbar in that control. I'm setting the transparent
property of the toolbar to True because I want to see the parent
background.
But the problem is that I'm getting a black background for the toolbar
instead to see the parent background portion.

Can someone help me on this please?

Thanks!

Antony

Bill Bateman · Guest

Hello Antony,

Use the following code to draw a transparent image to the canvas first,
then draw everything else to that canvas after. It is working great
for me!

procedure DrawParentImage(Control: TControl; Dest: TCanvas);
var
SaveIndex: Integer;
DC: HDC;
Position: TPoint;
begin
with Control do
begin
if Parent = nil then
Exit;
DC := Dest.Handle;
SaveIndex := SaveDC(DC);
{$IFDEF DFS_COMPILER_2}
GetViewportOrgEx(DC, @Position);
{$ELSE}
GetViewportOrgEx(DC, Position);
{$ENDIF}
SetViewportOrgEx(DC, Position.X - Left, Position.Y - Top, nil);
IntersectClipRect(DC, 0, 0, Parent.ClientWidth,
Parent.ClientHeight);
Parent.Perform(WM_ERASEBKGND, DC, 0);
Parent.Perform(WM_PAINT, DC, 0);
RestoreDC(DC, SaveIndex);
end;
end;

Bill