The code which follows displays three columns, CheckBox, Text, Text. The last column is displayed for testing to mimic changes in real time. My question is, how can I get the checkbox column when clicked to update based on code in the CellContentClick event (is this the proper event)of the DataGridView w/o leaving the current row?
Private Sub frmTinkering_Load() Handles MyBase.Load
LoadDataAndConfigureGridView()
End Sub
Private Sub LoadDataAndConfigureGridView()
DataGridView1.AutoGenerateColumns = False
DataGridView1.AllowUserToAddRows = False
Dim ColumnExpression As String = _
"IIF(UnderlyingData = 'A','True','False')"
Dim Table As New DataTable
With Table.Columns
.AddRange(New DataColumn() _
{ _
New DataColumn("UnderlyingData", _
System.Type.GetType("System.String")), _
New DataColumn("FruitData", _
System.Type.GetType("System.String")), _
New DataColumn("CheckBoxData", _
System.Type.GetType("System.String"), _
ColumnExpression) _
} _
)
End With
Table.Rows.Add(New Object() {"A", "Apples"})
Table.Rows.Add(New Object() {"B", "Grapes"})
Table.Rows.Add(New Object() {Nothing, "Pears"})
Dim CheckList As New DataGridViewCheckBoxColumn
With CheckList
.HeaderText = "A/B"
.DataPropertyName = "CheckBoxData"
.Name = "CheckBoxData"
End With
Dim Fruit As New DataGridViewTextBoxColumn
With Fruit
.HeaderText = "Favs"
.DataPropertyName = "FruitData"
End With
Dim Source As New DataGridViewTextBoxColumn
With Source
.HeaderText = "Source"
.DataPropertyName = "UnderlyingData"
.Name = "Source"
End With
DataGridView1.Columns.AddRange(New DataGridViewColumn() _
{CheckList, Fruit, Source})
DataGridView1.DataSource = Table
End Sub
Private Sub DataGridView1_CellContentClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
' Check = True if value is "A" else unchecked
Dim Grid As DataGridView = DirectCast(sender, DataGridView)
If e.ColumnIndex = Grid.FindColumnByName("CheckBoxData").Index Then
If Grid.Rows.Item(e.RowIndex).Cells(2).Value.ToString() = "A" Then
Grid.Rows.Item(e.RowIndex).Cells(2).Value = "B"
Else
Grid.Rows.Item(e.RowIndex).Cells(2).Value = "A"
End If
Grid.EndEdit()
End If
End Sub
VS2008 extension used above
<Runtime.CompilerServices.Extension()> _
Public Function FindColumnByName(ByVal GridView As DataGridView, _
ByVal ColumnName As String) _
As DataGridViewColumn
Dim Column As DataGridViewColumn = _
(From c In GridView _
.Columns.Cast(Of DataGridViewColumn)() _
Where c.Name.ToUpper = ColumnName.ToUpper).FirstOrDefault
If Not IsNothing(Column) Then
Return Column
Else
Throw New Exception(ColumnName & " not found")
End If
End Function
KSG | | Kevininstructor Wednesday, May 27, 2009 6:43 PM | Hi Kevininstructor,
"When I click on one of the checkboxes the value in the last column changes but the checkbox checked property only changes after I leave the current row. Same goes for if I change the value in the last column, the checkbox checked value does not change until leaving the row."
It's a by design behavior of DataGridView, even you call EndEdit won't take effect in this situation. DataGridView always commit data to the underline datasource when you leave the editing row. It is done within the DataGridView, so you cannot change it.
Sincerely,
Kira Qian
Please mark the replies as answers if they help and unmark if they don't. - Marked As Answer byKevininstructor Friday, May 29, 2009 1:59 PM
-
| | Kira Qian Friday, May 29, 2009 4:07 AM | So the code you are posting does not do the update? Or could you be more specific on your question? (Seriously consider replacing your IIF with the new ternary If statement.)
www.insteptech.com
We are volunteers and ask only that if we are able to help you, that you mark our reply as your answer. THANKS! | | DeborahK Wednesday, May 27, 2009 11:24 PM | Actually, just found this in the help system: "For clicks in a DataGridViewCheckBoxCell, this event occurs before the check box changes value, so if you do not want to calculate the expected value based on the current value, you will typically handle the DataGridView..::.CellValueChanged event instead." Here is the link: http://msdn.microsoft.com/en-us/library/system.windows.forms.datagridview.cellcontentclick.aspxHope this helps.
www.insteptech.com
We are volunteers and ask only that if we are able to help you, that you mark our reply as your answer. THANKS! | | DeborahK Wednesday, May 27, 2009 11:28 PM | So the code you are posting does not do the update? Or could you be more specific on your question?
(Seriously consider replacing your IIF with the new ternary If statement.)
www.insteptech.com
We are volunteers and ask only that if we are able to help you, that you mark our reply as your answer. THANKS!
Thanks for your reply! When I click on one of the checkboxes the value in the last column changes but the checkbox checked property only changes after I leave the current row. Same goes for if I change the value in the last column, the checkbox checked value does not change until leaving the row. What I want is for the checkbox to change when either clicking on the checkbox or changing the value of the last column
KSG | | Kevininstructor Thursday, May 28, 2009 1:05 PM | Actually, just found this in the help system:
"For clicks in a DataGridViewCheckBoxCell, this event occurs before the check box changes value, so if you do not want to calculate the expected value based on the current value, you will typically handle the DataGridView..::.CellValueChanged event instead."
Here is the link:
http://msdn.microsoft.com/en-us/library/system.windows.forms.datagridview.cellcontentclick.aspx
Hope this helps.
www.insteptech.com
We are volunteers and ask only that if we are able to help you, that you mark our reply as your answer. THANKS!
I looked at the docs, tried
If DataGridView1.IsCurrentCellDirty Then
DataGridView1.CommitEdit(DataGridViewDataErrorContexts.Commit)
End If
along with
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'DataGridView1.Focus()
DataGridView1.Rows.Item(DataGridView1.CurrentRow.Index).Cells(2).Value = "A"
'DataGridView1.InvalidateRow(DataGridView1.CurrentRow.Index)
DataGridView1.Invalidate()
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
'DataGridView1.Focus()
DataGridView1.Rows.Item(DataGridView1.CurrentRow.Index).Cells(2).Value = "B"
'DataGridView1.InvalidateRow(DataGridView1.CurrentRow.Index)
DataGridView1.Invalidate()
End Sub
and get the code to work with invoking either of the two click events two times but never with once click. At least there is some progress but not solved.
KSG | | Kevininstructor Thursday, May 28, 2009 2:11 PM | The help system (from how I was reading) just suggested changing this: Private Sub DataGridView1_CellContentClick( ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick ' Check = True if value is "A" else unchecked Dim Grid As DataGridView = DirectCast(sender, DataGridView) If e.ColumnIndex = Grid.FindColumnByName( "CheckBoxData").Index Then If Grid.Rows.Item(e.RowIndex).Cells(2).Value.ToString() = "A" Then Grid.Rows.Item(e.RowIndex).Cells(2).Value = "B" Else Grid.Rows.Item(e.RowIndex).Cells(2).Value = "A" End If Grid.EndEdit() End If End SubTo use the CellValueChanged event instead of the CellContextClick event. Did that not work for you?
www.insteptech.com
We are volunteers and ask only that if we are able to help you, that you mark our reply as your answer. THANKS! | | DeborahK Thursday, May 28, 2009 4:06 PM | The help system (from how I was reading) just suggested changing this:
Private Sub DataGridView1_CellContentClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
' Check = True if value is "A" else unchecked
Dim Grid As DataGridView = DirectCast(sender, DataGridView)
If e.ColumnIndex = Grid.FindColumnByName("CheckBoxData").Index Then
If Grid.Rows.Item(e.RowIndex).Cells(2).Value.ToString() = "A" Then
Grid.Rows.Item(e.RowIndex).Cells(2).Value = "B"
Else
Grid.Rows.Item(e.RowIndex).Cells(2).Value = "A"
End If
Grid.EndEdit()
End If
End Sub
To use the CellValueChanged event instead of the CellContextClick event. Did that not work for you?
www.insteptech.com
We are volunteers and ask only that if we are able to help you, that you mark our reply as your answer. THANKS!
I read the documentation that you provided a link to and saw that Checkbox columns need to be handled differently so I followed their suggestion to invoke CommitEdit(DataGridViewDataErrorContexts.Commit) followed by called .Invalidate method against the entire DataGridView with the code above in CellValueChanged but the Checkbox still is not updating until leaving the current row. Also tried the above in " CurrentCellDirtyStateChanged event" I got some irregular changing of the Checkbox by forcing the data to change in click events of two command buttons
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
DataGridView1.Rows.Item(DataGridView1.CurrentRow.Index).Cells(2).Value = "A"
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
DataGridView1.Rows.Item(DataGridView1.CurrentRow.Index).Cells(2).Value = "B"
End Sub
If I invoke either button say two or three times I would first see a flash of the checkbox changing on the second execution of the code then on the third time and there after it would seem to work which is simply driving me batty :-[ Any ways thanks again for taking the time to assist me!!!
KSG | | Kevininstructor Thursday, May 28, 2009 8:00 PM | I dug out some old code and found that I used that as well: CurrentCellDirtyStateChanged.
I had to check for which cell's state was changed and if it was the one I wanted, I could make the other columns change to match.
What happened when you tried CurrentCellDirtyStateChanged?
www.insteptech.com
We are volunteers and ask only that if we are able to help you, that you mark our reply as your answer. THANKS! | | DeborahK Thursday, May 28, 2009 8:27 PM | Hi Kevininstructor,
"When I click on one of the checkboxes the value in the last column changes but the checkbox checked property only changes after I leave the current row. Same goes for if I change the value in the last column, the checkbox checked value does not change until leaving the row."
It's a by design behavior of DataGridView, even you call EndEdit won't take effect in this situation. DataGridView always commit data to the underline datasource when you leave the editing row. It is done within the DataGridView, so you cannot change it.
Sincerely,
Kira Qian
Please mark the replies as answers if they help and unmark if they don't. - Marked As Answer byKevininstructor Friday, May 29, 2009 1:59 PM
-
| | Kira Qian Friday, May 29, 2009 4:07 AM |
Hi Kevininstructor,
"When I click on one of the checkboxes the value in the last column changes but the checkbox checked property only changes after I leave the current row. Same goes for if I change the value in the last column, the checkbox checked value does not change until leaving the row."
It's a by design behavior of DataGridView, even you call EndEdit won't take effect in this situation. DataGridView always commit data to the underline datasource when you leave the editing row. It is done within the DataGridView, so you cannot change it.
Sincerely,
Kira Qian
Please mark the replies as answers if they help and unmark if they don't.
Thanks for the explaination. I was kind of figuring this was the case that it can not be changed. It would be nice to be able to thou.
KSG | | Kevininstructor Friday, May 29, 2009 1:59 PM |
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index > Windows Forms Data Controls and Databinding > Update CheckBox Column based on another underlying column with an expression