Re: bitmaps in TListbox reappear

besh_at_cix.compulink.co.uk
Date: 03/29/05 

Date: Tue, 29 Mar 2005 14:23:02 -0600

> What does your OnDrawItem event look like?

Here's the full proc

procedure TForm1.ListBox3DrawItem(Control: TWinControl; Index: Integer;
  Rect: TRect; State: TOwnerDrawState);
var
    Bitmap: TBitmap;
begin
    with (Control as TListBox).Canvas do
    begin
      try
      FillRect(Rect);
      Bitmap := getmodimage( strtoint(getitemdata(inttostr(index), '4')),
                             getfbbx(1), inttostr(index), 1);
      if Bitmap <> nil then
      begin
        BrushCopy(Bounds(Rect.Left + 2, Rect.Top, Bitmap.Width,
            Bitmap.Height), Bitmap, Bounds(0, 0, Bitmap.Width,
            Bitmap.Height), clRed);
      end;
      finally
      bitmap.free
      end;
    end;
end;

getmodimage is a function that returns a TBitmap;

function GetModImage(wid, heit:integer;charval: string; sze:integer):
TBitmap;

showing the bitmap creation part
    result := Tbitmap.create;
    result.width := wid;
    result.height := heit;
    result.monochrome := true;
    result.pixelformat := pfDevice; //changed to pfdevice from pf1bit
    
    the rest is just bitmap drawing routines.
    
    Since Result is a TBitmap, it cannot be freed within the function.
However the bitmap is freed in the OnDrawItem procedure.

The code works beautifylly, but for the listbox items not 'refreshing'.

Neil

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