Tooltip

Updated on May 7, 2026

To set a ToolTip value to the RadGanttView elements, we can use the ToolTipTextNeeded event. In its event handler we can set different value of ToolTipText property for the currently hover element.

C#

private void radGanttView1_ToolTipTextNeeded(object sender, ToolTipTextNeededEventArgs e)
{
    GanttViewTaskElement taskElement = sender as GanttViewTaskElement;
    GanttViewMilestoneElement mileStone = sender as GanttViewMilestoneElement;
    GanttViewSummaryElement summaryItem = sender as GanttViewSummaryElement;


    if (mileStone != null)
    {
GanttViewMilestoneItemElement itemElement = mileStone.Parent as GanttViewMilestoneItemElement;

e.ToolTipText = itemElement.Data.Title + " : " + itemElement.Data.Start.ToShortDateString() + " - " + itemElement.Data.End.ToShortDateString();
    }

    if (summaryItem != null)
    {
GanttGraphicalViewBaseItemElement itemElement = summaryItem.Parent as GanttGraphicalViewBaseItemElement;

e.ToolTipText = itemElement.Data.Title + " : " + itemElement.Data.Start.ToShortDateString() + " - " + itemElement.Data.End.ToShortDateString();
    }

    if (taskElement != null)
    {
GanttGraphicalViewBaseItemElement itemElement = taskElement.Parent as GanttGraphicalViewBaseItemElement;

if (itemElement != null)
    e.ToolTipText = itemElement.Data.Title + " : " + itemElement.Data.Start.ToShortDateString() + " - " + itemElement.Data.End.ToShortDateString();
    }
}

VB.NET

Private Sub radGanttView1_ToolTipTextNeeded(sender As Object, e As ToolTipTextNeededEventArgs)
    Dim taskElement As GanttViewTaskElement = TryCast(sender, GanttViewTaskElement)
    Dim mileStone As GanttViewMilestoneElement = TryCast(sender, GanttViewMilestoneElement)
    Dim summaryItem As GanttViewSummaryElement = TryCast(sender, GanttViewSummaryElement)


    If mileStone IsNot Nothing Then
        Dim itemElement As GanttViewMilestoneItemElement = TryCast(mileStone.Parent, GanttViewMilestoneItemElement)

        e.ToolTipText = itemElement.Data.Title & " : " & itemElement.Data.Start.ToShortDateString() & " - " + itemElement.Data.[End].ToShortDateString()
    End If

    If summaryItem IsNot Nothing Then
        Dim itemElement As GanttGraphicalViewBaseItemElement = TryCast(summaryItem.Parent, GanttGraphicalViewBaseItemElement)

        e.ToolTipText = itemElement.Data.Title & " : " & itemElement.Data.Start.ToShortDateString() & " - " + itemElement.Data.[End].ToShortDateString()
    End If

    If taskElement IsNot Nothing Then
        Dim itemElement As GanttGraphicalViewBaseItemElement = TryCast(taskElement.Parent, GanttGraphicalViewBaseItemElement)

        If itemElement IsNot Nothing Then
            e.ToolTipText = itemElement.Data.Title & " : " & itemElement.Data.Start.ToShortDateString() & " - " + itemElement.Data.[End].ToShortDateString()
        End If
    End If
End Sub

The code snippet below demonstrates how you can use ToolTipTextNeeded event handler to set ToolTipText for the given element.

See Also

• Properties