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The Tooltip represents a small rectangular window that displays a brief description when the user hovers over control or an element. All controls have the ToolTipTextNeeded event which can be used for dynamically setting the text of the tooltips.

Figure 1: Tooltip on a grid cells.


Using the ToolTipTextNeeded event.

The following example shows how you can use the ToolTipTextNeeded event to show a tooltip on a RadListView item. In addition the ToolTipTextNeededEventArgs object gives you access to the tooltip instance.

Setting the tooltip text in the ToolTipTextNeeded event handler.

private void RadListControl1_ToolTipTextNeeded(object sender, Telerik.WinControls.ToolTipTextNeededEventArgs e)
    var item = sender as RadListVisualItem;
    if (item != null)
        var dataItem = item.Data as RadListDataItem;
        e.ToolTipText = dataItem.Value.ToString();

Private Sub RadListControl1_ToolTipTextNeeded(ByVal sender As Object, ByVal e As Telerik.WinControls.ToolTipTextNeededEventArgs)
    Dim item = TryCast(sender, RadListVisualItem)
    If item IsNot Nothing Then
        Dim dataItem = TryCast(item.Data, RadListDataItem)
        e.ToolTipText = dataItem.Value.ToString()
    End If
End Sub

Figure 2: The result from the above code.


See Also

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