ColorEachPoint and Gradient?

[Jim Green]

Hello, is it possible to use BarSeries.ColorEachPoint and have a gradient?

Thanks.

[Yeray]

Hi,

Yes, you can. Ie:

Code: Select all

  with Chart1.AddSeries(TBarSeries) as TBarSeries do
  begin
    FillSampleValues;
    ColorEachPoint:=true;
    BarStyle:=bsRectGradient;
  end;

[Jim Green]

Yeray, I should have mentioned that I'm specifying the colors - positive values in green and negative in red, but a gradient version of each color. So I have:

Code: Select all

      if series.ColorEachPoint then
        if y < y0 then
          color := clRed
        else
          color := clGreen
      else
        color := clDefault;
      series.AddXY(x, y, '', color);

Where would you supply the 2nd color for the gradient?

Thanks,
Jim

[Yeray]

Hi Jim,

Where would you supply the 2nd color for the gradient?

You should set the series' Gradient.StartColor property.
However this is a color for the whole series. If you want to set a different StartColor for each point, you could use the OnGetPointerStyle/OnGetBarStyle event to change that color each time a point/bar is going to be drawn.

Code: Select all

Procedure TForm1.GetBarStyle(Sender:TCustomBarSeries; ValueIndex:Integer; var TheBarStyle:TBarStyle);
begin
  Sender.Gradient.StartColor:=ApplyBright(Sender.ValueColor[ValueIndex], 128);
end;