Tooltips

Updated over 6 months ago

The tooltips are supported out of the box and you just need to enable them.

Enable tooltips

C#

radSparkline1.ShowToolTip = true;

VB.NET

radSparkline1.ShowToolTip = True

The default tooltips will displayed when hovering over a particular data point.

Customizing Tooltip Text

You can use the DataPointTooltipTextNeeded event to set custom tooltip text. The following snippet shows how you can access the event.

Subscribing to DataPointTooltipTextNeeded

C#

var toolTipControler = new SparkTooltipController();
toolTipControler.DataPointTooltipTextNeeded += ToolTipControler_DataPointTooltipTextNeeded;
radSparkline1.Controllers.Add(toolTipControler);

VB.NET

Dim toolTipControler = New SparkTooltipController()
AddHandler toolTipControler.DataPointTooltipTextNeeded, AddressOf ToolTipControler_DataPointTooltipTextNeeded
radSparkline1.Controllers.Add(toolTipControler)

The following example shows how you can set the text in the event handler.

Customizing the Tooltip Text

C#

private void ToolTipControler_DataPointTooltipTextNeeded(object sender, Telerik.WinControls.UI.Sparkline.SparkDataPointTooltipTextNeededEventArgs e)
{
    var point = e.DataPoint as CategoricalSparkDataPoint;
    if (point.Value > 10)
    {
        e.Text = "Value Critical";
    }
    else
    {
        e.Text = "Normal Vlaue";
    }
}

VB.NET

Private Sub ToolTipControler_DataPointTooltipTextNeeded(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.Sparkline.SparkDataPointTooltipTextNeededEventArgs)
    Dim point = TryCast(e.DataPoint, CategoricalSparkDataPoint)
    If point.Value > 10 Then
        e.Text = "Value Critical"
    Else
        e.Text = "Normal Vlaue"
    End If
End Sub