Fill colors

afhacker
27 Nov 2018, 08:35

Hi Alexander,

Anytime you call chart class "Draw***" methods the method returns back the object, so suppose you have called the "DrawRectangle" method and you want to make it filled or interactive:

        public override void Calculate(int index)
        {
            if (IsLastBar)
            {
                // Here we are making the color transparent
                Color color = Color.FromArgb(50, Color.Blue);
                // you can use var instead of class name
                ChartRectangle rectangle = Chart.DrawRectangle("rectangle", index - 40, MarketSeries.Low[index - 40], index, MarketSeries.High[index - 40], color, 1, LineStyle.Dots);
                // This will fill the object
                rectangle.IsFilled = true;
                // This will allow the user to modify the object
                rectangle.IsInteractive = true;
            }
        }

The above code only works on cTrader 3.3 or above.

The way Spotware is designed the new chart drawing isn't good enough or at least that's how I think, I liked it to be like this:

        public override void Calculate(int index)
        {
            if (IsLastBar)
            {
                ChartRectangle rectangle = new ChartRectangle
                {
                    Name = "rectangle",
                    FirstBarIndex = index - 40,
                    SecondBarIndex = index,
                    High = MarketSeries.High[index - 40],
                    Low = MarketSeries.Low[index - 40],
                    Color = Color.FromArgb(50, Color.Blue),
                    Thickness = 1,
                    LineStyle = LineStyle.Dots,
                    IsFilled = true,
                    IsInteractive = true
                };

                Chart.Objects.Add(rectangle);
            }
        }

That way we were able to create our own chart object classes by inheriting from current object classes and it was opening the door for more creative ideas.

alexander.n.fedorov
27 Nov 2018, 10:24

Thank you very much

Regards

Sasha

jani
14 Dec 2019, 22:17

RE:

Thank you very much for the very helpfull example! For a beginner like myself, it is sometimes quite impossible to figure out the actual code from API reference.

Could any tell how can I draw histograms with opacity?  I have :

        [Output("Histogram Down", PlotType = PlotType.Histogram, LineColor = "Red")]
        public IndicatorDataSeries HistogramNegative { get; set; }

How can I use  in this public output parameter definition the below opacity setting?:

       Color color = Color.FromArgb(50, Color.Red);

PanagiotisCharalampous
16 Dec 2019, 09:01

RE:

Hi Jan,

You cannot apply a color for an indicator series on runtime. You can only apply it on declaration. To apply opacity, you can set a HEX code as a color. See below

[Output("Histogram Down", PlotType = PlotType.Histogram, LineColor = "#32FF0000")]

Best Regards,

Panagiotis