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CrosshairGroupHeaderElement Class

Defines the appearance of the crosshair group header element when custom drawing a crosshair cursor using the ChartControl.CustomDrawCrosshair event.

Namespace: DevExpress.XtraCharts

Assembly: DevExpress.XtraCharts.v24.1.dll

NuGet Package: DevExpress.Charts

Declaration

public class CrosshairGroupHeaderElement :
    BaseCrosshairLabelElement

The following members return CrosshairGroupHeaderElement objects:

Remarks

To access the appearance properties of the CrosshairGroupHeaderElement object , use the CustomDrawCrosshairEventArgs.CrosshairGroupHeaderElements property when custom drawing a crosshair cursor using the ChartControl.CustomDrawCrosshair event handler.

For more information on crosshair cursors, see Tooltip and Crosshair Cursor.

Example

This example shows how to use the ChartControl.CustomDrawCrosshair event to create a custom appearance for the crosshair cursor. This event is invoked when you select the Custom Draw Crosshair Cursor check box.

Custom draw a crosshair cursor

If you wish to display crosshair axis lines and labels on a chart before custom drawing the crosshair cursor, set the CrosshairOptions.ShowArgumentLine, CrosshairOptions.ShowArgumentLabels, CrosshairOptions.ShowValueLabels and CrosshairOptions.ShowValueLine properties to true.

Note that the crosshair cursor customization is available for the CrosshairOptions.SnapMode property set to NearestArgument.

View Example

using System;
using System.Drawing;
using System.Windows.Forms;
using DevExpress.Drawing;
using DevExpress.XtraCharts;

namespace CustomDrawCrosshairCursor {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }
        private void OnCheckEditCheckedChanged(object sender, EventArgs e) {
            if (checkEdit1.Checked)
                chartControl1.CustomDrawCrosshair += OnChartControlCustomDrawCrosshair;
            else 
                chartControl1.CustomDrawCrosshair -= OnChartControlCustomDrawCrosshair;               
        }

        private void OnChartControlCustomDrawCrosshair(object sender, CustomDrawCrosshairEventArgs e) {
            // Specify the crosshair argument line color, dash style and thickness.
            e.CrosshairLineElement.Color = Color.Green;
            e.CrosshairLineElement.LineStyle.DashStyle = DashStyle.DashDot;
            e.CrosshairLineElement.LineStyle.Thickness = 3;

            // Specify the back color for the crosshair argument axis label. 
            foreach (CrosshairAxisLabelElement axisLabelElement in e.CrosshairAxisLabelElements)
                axisLabelElement.BackColor = Color.Blue;

            foreach (CrosshairElementGroup group in e.CrosshairElementGroups) {
                CrosshairGroupHeaderElement groupHeaderElement = group.HeaderElement;

                // Specify the text, text color and font for the crosshair group header element. 
                groupHeaderElement.Text = "Custom draw";
                groupHeaderElement.TextColor = Color.Green;
                groupHeaderElement.DXFont = new DXFont("SegoeUI", 12, DXFontStyle.Bold);

                // Obtain the first series.
                CrosshairElement element = group.CrosshairElements[0];

                // Specify the color, dash style and thickness for the crosshair value lines. 
                element.LineElement.Color = Color.DarkViolet;
                element.LineElement.LineStyle.DashStyle = DashStyle.Dash;
                element.LineElement.LineStyle.Thickness = 2;

                // Specify the text color and back color for the crosshair value labels.
                element.AxisLabelElement.TextColor = Color.Red;
                element.AxisLabelElement.BackColor = Color.Yellow;

                // Format the text shown for the series in the crosshair cursor label. Specify the text color and marker size. 
                element.LabelElement.TextColor = Color.Red;
                element.LabelElement.MarkerSize = new Size(15, 15);
                element.LabelElement.Text = string.Format("{0}: A={1}; V={2}", element.Series.Name, element.SeriesPoint.Argument, element.SeriesPoint.Values[0]);
            }
        }
    }
}

Inheritance

Object
BaseCrosshairLabelElement
CrosshairGroupHeaderElement
See Also