SelectionTool blocks

TeeChart .NET
1

7-19-2010 10-10-58 PM.png
As shown in above image, the selection tool puts too many black blocks. Is there a way I can have only at the beginning, middle and at end?

Also, is there a way I can set the transparency of these blocks. Sometimes they are pretty much cover the whole curve that is being selected.
Thanks,

2

Hi asupriya,

I’m afraid it only can be done manually right now. You could use Selected event to calculate the points to draw and draw them using a Points series or drawing them manually at AfterDraw event.

Yes, check the Selector tool’s property: Brush.Transparency

3

Can you please post a code snippet for this? I am using fastline series. Appreciate your help.

4

Hi asupriya ,

Here you have an example to start with:

        private Steema.TeeChart.Tools.Selector select1;
        private Steema.TeeChart.Styles.Line line1;
        private Point[] points;

        private void InitializeChart()
        {
            tChart1.Aspect.View3D = false;

            line1 = new Steema.TeeChart.Styles.Line(tChart1.Chart);
            line1.FillSampleValues(1000);

            select1 = new Steema.TeeChart.Tools.Selector(tChart1.Chart);
            select1.DrawHandles = false;

            points = new Point[3];
            select1.Selected += new Steema.TeeChart.Tools.SelectorSelectedEventHandler(select1_Selected);

            tChart1.AfterDraw += new Steema.TeeChart.PaintChartEventHandler(tChart1_AfterDraw);
        }

        void select1_Selected(object sender, EventArgs e)
        {
            if (select1.Selection == line1)
            {
                points[0].X = line1.CalcXPos(0);
                points[0].Y = line1.CalcYPos(0);

                points[1].X = line1.CalcXPos(line1.Count / 2);
                points[1].Y = line1.CalcYPos(line1.Count / 2);

                points[2].X = line1.CalcXPos(line1.Count-1);
                points[2].Y = line1.CalcYPos(line1.Count - 1);
            }
        }

        void tChart1_AfterDraw(object sender, Steema.TeeChart.Drawing.Graphics3D g)
        {
            if (select1.Selection == line1)
            {
                int width = 6;
                Steema.TeeChart.Drawing.Graphics3D gd = tChart1.Graphics3D;
                gd.Brush.Color = Color.Red;
                gd.Brush.Transparency = 50;
                
                for (int i = 0; i < points.Length; i++)
                {
                    gd.Rectangle(points[i].X - width, points[i].Y - width, points[i].X + width, points[i].Y + width);    
                }
                
            }
        }
5

Thanks Yeray for the code snippet. Really appreciate it.

6

Hi asupriya,

You’re welcome! :slight_smile: