Article #27718: How can I make the background color different for alternating lines of text in a TListBox in Delphi?

QUESTION:

How can I make the background color different for alternating lines of text in a TListBox in Delphi?

ANSWER:

Here is one way of accomplishing this. After dropping a TListBox on your form, you must change the Style property of the TListBox to lbOwnerDrawFixed. If you fail to change the Style property, the OnDrawItem event will never be called. Put the following code in the OnDrawItem event of your TListBox:

procedure TForm1.ListBox1DrawItem(Control: TWinControl; Index: Integer;
Rect: TRect; State: TOwnerDrawState);
var
myColor: TColor;
myBrush: TBrush;
begin
myBrush := TBrush.Create;
with (Control as TListBox).Canvas do // draw on control canvas, not on the form
begin
if not Odd(Index) then
myColor := clSilver
else
myColor := clYellow;
myBrush.Style := bsSolid;
myBrush.Color := myColor;
Windows.FillRect(handle, Rect, myBrush.Handle);
Brush.Style := bsClear;
// display the text 
TextOut(Rect.Left, Rect.Top, (Control as TListBox).Items[Index]);
MyBrush.Free;
end;
end;

Last Modified: 19-SEP-01