anchor.diff:    sw: integer;
   begin
     if FVScrollBar.Visible then
  -    sw := FVScrollBar.Width-1
  +    sw := FVScrollBar.Width
     else
       sw := 0;
  -  Result := Width - (FMargin*2) - sw;
  +  Result := GetClientRect.Width - sw
   end;
   
   function TfpgBaseGrid.VisibleHeight: integer;
  
positive.code:     hh := 0;
    if ShowHeader then
      hh := hh + FHeaderHeight+1;
    Result := (Height - (2*FMargin) - hh) div FDefaultRowHeight;
  end;
  
  function TfpgBaseGrid.VisibleWidth: integer;
  
negative.code:     hh : integer; // header height
    begin
      hh := 0;
      if ShowHeader then
        inc (hh, FHeaderHeight+1);
      if showH then
        inc (hh, FHScrollBar.Height);
      vl := (VHeight - hh) div FDefaultRowHeight;
      Vfits := vl >= RowCount;
    end;
  