FAQ Item: Why does the DataGridView not show up the RowHeader on the second tab of a TabControl?

Question

Why does the DataGridView not show up the RowHeader on the second tab of a TabControl?

Answer 1

The cause of this issue is that the DataGridView is not updated while it is hidden. We can use the TabControl’s SelectedIndexChanged event to work around the problem. Every time a tab is selected, this event occurs, and then we call DataGridView.Invalidate() to force the DataGridView to be redrawn.

Codes:

    Public Sub Tab_Changes(ByVal sender As System.Object, ByVal e As System.EventArgs)

        ' use this sub to track if a tab is selected in the tab control & force a row and column redraw

        Dim tabC As TabControl

        Dim dgvChart As DataGridView

        Dim strTab As String

 

        'cast to TabControl to work with

        If TypeOf sender Is TabControl Then

            tabC = DirectCast(sender, TabControl)

 

            'cast to DGV to work with

            If TypeOf tabC.TabPages(tabC.SelectedIndex).Controls(dgvChart.Name) Is DataGridView Then

                dgvChart = DirectCast(tabC.TabPages(tabC.SelectedIndex).Controls(DataGridView1.Name), DataGridView)

 

                'Invalidate the tabpage's dgv

                dgvChart.Invalidate()

 

                ' OR call a bespoke sub called Sub_DGVRedraw(Byval dgvInput as DataGridView) that will redraw the headers

                Sub_DGVRedraw(dgvChart)

            End If

        End If

    End Sub

 

Related threads:

http://social.msdn.microsoft.com/Forums/en-US/vbgeneral/thread/00c461e7-7a83-43da-b60e-fb192463166d

http://social.msdn.microsoft.com/Forums/en-US/winformsdatacontrols/thread/b4f5079c-c8f1-4a2d-a476-8cbef1e0debb

http://social.msdn.microsoft.com/forums/en-US/winformsdatacontrols/thread/44e13cb2-15e2-4b40-b8ed-9adb80e9b6c7/

 

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