The arrow pointer in a TStringGrid

Question

Is it possible to add that arrow pointer thing to a String Grind in Delphi 7? You know what I mean, that arrow pointer that you can see at the left in a DBGrid.

Answer 1

Yes, but not automatically. You would need to display a triangle manually. You can override OnDrawCell for your grid. It seems you need to set the FixedCols to 0 since it doesn't appear to redraw the fixed cells again when the row selection changes.

procedure TForm1.StringGrid1DrawCell(Sender: TObject; ACol, ARow: Integer;
  Rect: TRect; State: TGridDrawState);
var
  aCanvas: TCanvas;
  oldColor: TColor;
  triangle: array [0..2] of TPoint;
const
  spacing = 4;
begin
  if (ACol = 0) and (aRow = StringGrid1.Row) then
  begin
    aCanvas := (Sender as TStringGrid).Canvas;  // To avoid with statement
    oldColor := aCanvas.Brush.Color;
    // Shape the triangle
    triangle[0] := TPoint.Create(Rect.Left + spacing, Rect.Top + spacing);
    triangle[1] := TPoint.Create(Rect.Left + spacing, Rect.Top + Rect.Height - spacing);
    triangle[2] := TPoint.Create(Rect.Left + Rect.Width - spacing, Rect.Top + Rect.Height div 2);

    // Draw the triangle
    aCanvas.Pen.Color := clBlack;
    aCanvas.Brush.Color := clBlack;
    aCanvas.Polygon(triangle);
    aCanvas.FloodFill(Rect.Left + Rect.Width div 2, Rect.Top + Rect.Height div 2, clBlack, fsSurface);
    aCanvas.Brush.Color := oldColor;
  end;
end;

This draws a triangle in the box. You should get the general idea.