How to: Add Tooltips for the Row Indicator in XtraGrid

• Nov 13, 2018
• 2 minutes to read

The following example demonstrates a way of implementing custom tooltips for row indicator cells in the XtraGrid control. By default, the grid control does not support tooltips for row indicator cells. To provide tooltips, drop the ToolTipController component onto the grid’s form, assign it to the grid control’s EditorContainer.ToolTipController property and handle the ToolTipController.GetActiveObjectInfo event.

In our example, the tooltips will display the “Row N” text where N is the ordinal number of a row.

C#

using DevExpress.Utils;
using DevExpress.XtraGrid.Views.Grid;
using DevExpress.XtraGrid.Views.Grid.ViewInfo;
//...
private void toolTipController1_GetActiveObjectInfo(object sender, 
ToolTipControllerGetActiveObjectInfoEventArgs e) {
    if(e.SelectedControl != gridControl1) return;

    ToolTipControlInfo info = null;
    //Get the view at the current mouse position
    GridView view = gridControl1.GetViewAt(e.ControlMousePosition) as GridView;
    if(view == null) return;
    //Get the view's element information that resides at the current position
    GridHitInfo hi = view.CalcHitInfo(e.ControlMousePosition);
    //Display a hint for row indicator cells
    if(hi.HitTest == GridHitTest.RowIndicator) {
        //An object that uniquely identifies a row indicator cell
        object o = hi.HitTest.ToString() + hi.RowHandle.ToString();
        string text = "Row "+ hi.RowHandle.ToString();
        info = new ToolTipControlInfo(o, text);         
    }
    //Supply tooltip information if applicable, otherwise preserve default tooltip (if any)
    if (info != null)
        e.Info = info;
}

VB.NET

Imports DevExpress.XtraGrid.Views.Grid
Imports DevExpress.XtraGrid.Views.Grid.ViewInfo

Private Sub ToolTipController1_GetActiveObjectInfo(ByVal sender As Object, _ 
ByVal e As DevExpress.Utils.ToolTipControllerGetActiveObjectInfoEventArgs) _
Handles ToolTipController1.GetActiveObjectInfo
    If Not e.SelectedControl Is gridControl1 Then Return

    Dim info As ToolTipControlInfo = Nothing
    'Get the view at the current mouse position
    Dim view As GridView = gridControl1.GetViewAt(e.ControlMousePosition)
    If view Is Nothing Then Return
    'Get the view's element information that resides at the current position
    Dim hi As GridHitInfo = view.CalcHitInfo(e.ControlMousePosition)
    'Display a hint for row indicator cells
    If hi.HitTest = GridHitTest.RowIndicator Then
        'An object that uniquely identifies a row indicator cell
        Dim o As Object = hi.HitTest.ToString() + hi.RowHandle.ToString()
        Dim text As String = "Row " + hi.RowHandle.ToString()
        info = New ToolTipControlInfo(o, text)
    End If
    'Supply tooltip information if applicable, otherwise preserve default tooltip (if any)
    If Not info Is Nothing Then e.Info = info
End Sub