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HeatmapHitInfo Class

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HeatmapHitInfo Class

Contains information about a specific point within a heatmap.

Namespace : DevExpress.XtraCharts.Heatmap

Assembly : DevExpress.XtraCharts.v25.2.dll

NuGet Package : DevExpress.Charts

Declaration

csharp
[RuntimeObject]
public class HeatmapHitInfo :
    ChartHitInfoBase
vb
<RuntimeObject>
Public Class HeatmapHitInfo
    Inherits ChartHitInfoBase

The following members return HeatmapHitInfo objects:

Remarks

HeatmapHitInfo objects are created when you call the HeatmapControl.CalcHitInfo method to obtain information about a specific point within the heatmap. This method requires you to pass a test point or its coordinates as a parameter.

The HeatmapHitInfo class properties can be grouped into three categories:

  • The properties that indicate whether the test point resides over a particular view element. For instance, the HeatmapHitInfo.InTitle property indicates whether the test point is over the heatmap title or not;
  • The properties that return heatmap elements themselves (for example, the Title property).
  • The HeatmapHitInfo.HitObject and HeatmapHitInfo.HitObjects properties that identify the topmost element or the collection of all visual elements which contains the test point.

Example

The following example shows how to determine what a heatmap element is in a test point, and collect information related to this element.

Call the HeatmapControl.CalcHitInfo method to obtain information about a specific point within the Heatmap Control. This method returns a HeatmapHitInfo object that contains information related to heatmap elements positioned in the test point.

csharp
using DevExpress.Utils;
using DevExpress.XtraCharts;
using DevExpress.XtraCharts.Heatmap;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace HeatmapMatrixAdapterSample {
    public partial class Form1 : Form {
        HeatmapControl heatmap;
        ToolTipController toolTipController = new ToolTipController();
        public Form1() {
            InitializeComponent();
            //...
            heatmap.MouseMove += HeatmapMouseMove;
            heatmap.MouseLeave += HeatmapMouseLeave;
        }

        private void HeatmapMouseMove(object sender, MouseEventArgs e) {
            HeatmapHitInfo hitInfo = heatmap.CalcHitInfo(e.Location);
            StringBuilder builder = new StringBuilder();
            if (hitInfo.InAxis) {
                builder.AppendLine($"In axis: {hitInfo.Axis.Name}");
                if (hitInfo.AxisLabelItem != null)
                    builder.AppendLine($" Label: {hitInfo.AxisLabelItem.Text}");
                if (hitInfo.AxisTitle != null)
                    builder.AppendLine($" Axis title: {hitInfo.AxisTitle.Text}");
            }
            if (hitInfo.InCell)
                builder.AppendLine($" In cell: X ({hitInfo.Cell.XArgument}), Y ({hitInfo.Cell.YArgument})");
            if (hitInfo.InTitle)
                builder.AppendLine($" In title: {hitInfo.Title.Text}");
            if (hitInfo.InLegend)
                builder.AppendLine($" In legend");

            if (builder.Length > 0)
                toolTipController.ShowHint($"Hit-testing results:\n {builder}", heatmap.PointToScreen(e.Location));
            else
                toolTipController.HideHint();
        }
        private void HeatmapMouseLeave(object sender, System.EventArgs e) {
            toolTipController.HideHint();
        }
    }
}
vb
Imports DevExpress.Utils
Imports DevExpress.XtraCharts
Imports DevExpress.XtraCharts.Heatmap
Imports System.Text
Imports System.Windows.Forms

Namespace HeatmapMatrixAdapterSample
    Public Partial Class Form1
        Inherits Form

        Private heatmap As HeatmapControl
        Private toolTipController As ToolTipController = New ToolTipController()

        Public Sub New()
            InitializeComponent()
            '...
            Me.heatmap.MouseMove += AddressOf HeatmapMouseMove
            Me.heatmap.MouseLeave += AddressOf HeatmapMouseLeave
        End Sub

        Private Sub HeatmapMouseMove(ByVal sender As Object, ByVal e As MouseEventArgs)
            Dim hitInfo As HeatmapHitInfo = heatmap.CalcHitInfo(e.Location)
            Dim builder As StringBuilder = New StringBuilder()

            If hitInfo.InAxis Then
                builder.AppendLine($"In axis: {hitInfo.Axis.Name}")
                If hitInfo.AxisLabelItem IsNot Nothing Then builder.AppendLine($" Label: {hitInfo.AxisLabelItem.Text}")
                If hitInfo.AxisTitle IsNot Nothing Then builder.AppendLine($" Axis title: {hitInfo.AxisTitle.Text}")
            End If

            If hitInfo.InCell Then builder.AppendLine($" In cell: X ({hitInfo.Cell.XArgument}), Y ({hitInfo.Cell.YArgument})")
            If hitInfo.InTitle Then builder.AppendLine($" In title: {hitInfo.Title.Text}")
            If hitInfo.InLegend Then builder.AppendLine($" In legend")

            If builder.Length > 0 Then
                toolTipController.ShowHint($"Hit-testing results:
 {builder}", heatmap.PointToScreen(e.Location))
            Else
                toolTipController.HideHint()
            End If
        End Sub

        Private Sub HeatmapMouseLeave(ByVal sender As Object, ByVal e As EventArgs)
            toolTipController.HideHint()
        End Sub
    End Class
End Namespace

Inheritance

Object ChartHitInfoBase HeatmapHitInfo

See Also

HeatmapHitInfo Members

DevExpress.XtraCharts.Heatmap Namespace