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V25.1
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    HeatmapControl.CustomizeHeatmapToolTip Event

    Occurs before a tooltip is invoked and allows to customize tooltip content based on heatmap cell arguments and values.

    Namespace: DevExpress.XtraCharts.Heatmap

    Assembly: DevExpress.XtraCharts.v25.1.UI.dll

    NuGet Package: DevExpress.Win.Charts

    #Declaration

    public event CustomizeHeatmapToolTipEventHandler CustomizeHeatmapToolTip

    #Event Data

    The CustomizeHeatmapToolTip event's data class is CustomizeHeatmapToolTipEventArgs. The following properties provide information specific to this event:

    Property Description
    HeatmapCell Returns a heatmap cell for which a tooltip is shown.
    Text Gets or sets the cell tooltip text.
    Title Gets or sets the cell tooltip title.

    #Remarks

    The following example shows how to use the HeatmapControl.CustomizeHeatmapToolTip event to modify tooltip content based on the cell value for which the tooltip is shown.

    A tooltip customized in the CustomizeHeatmapToolTip handler.

    Follow the steps below to enable and customize tooltips:

    The code below applies a custom format to tooltip text if a heatmap cell value is more than the specified value:

    const int ThresholdValue = 50;
    
    public Form1() {
        InitializeComponent();
        // ...
        heatmap.ToolTipEnabled = true;
        heatmap.ToolTipController = new DevExpress.Utils.ToolTipController { AllowHtmlText = true };
        heatmap.CustomizeHeatmapToolTip += OnHeatmapCustomizeHeatmapToolTip;
    }
    
    private void OnHeatmapCustomizeHeatmapToolTip(object sender, CustomizeHeatmapToolTipEventArgs e) {
        double cellValue = (double)e.HeatmapCell.ColorValue;
        if (cellValue > ThresholdValue) {
            e.Title = "Sale Info";
            e.Text = $"Total: <color=green>${cellValue}K</color>";
        }
    }
    
    See Also