RadListView Unbound CellFormatting

[Brandon]

You have an excellent example of how to do CellFormatting on a Details ListView for a Bound list.  My issue is trying to mimmic the same effect with an unbound list.

Dim productRowView As DataRowView = TryCast(cell.Row.DataBoundItem, DataRowView)
If productRowView IsNot Nothing AndAlso CBool(productRowView.Row("Discontinued")) = True Then
    e.CellElement.BackColor = Color.Yellow
    e.CellElement.ForeColor = Color.Red
    e.CellElement.GradientStyle = Telerik.WinControls.GradientStyles.Solid
    e.CellElement.Font = newFont
Else
    e.CellElement.ResetValue(LightVisualElement.BackColorProperty, Telerik.WinControls.ValueResetFlags.Local)
    e.CellElement.ResetValue(LightVisualElement.ForeColorProperty, Telerik.WinControls.ValueResetFlags.Local)
    e.CellElement.ResetValue(LightVisualElement.GradientStyleProperty, Telerik.WinControls.ValueResetFlags.Local)
    e.CellElement.ResetValue(LightVisualElement.FontProperty, Telerik.WinControls.ValueResetFlags.Local)
End If

[Dimitar]

Hi Brandon,

You can acces a filed value by using the column name. Here is an example:

Private Sub RadListView1_CellFormatting(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.ListViewCellFormattingEventArgs)
    Dim cell As DetailListViewDataCellElement = TryCast(e.CellElement, DetailListViewDataCellElement)
    If cell IsNot Nothing Then
        Dim value = cell.Row("Column1").ToString()
        If value IsNot Nothing AndAlso value = "Test1" Then
            e.CellElement.BackColor = Color.Yellow
            e.CellElement.ForeColor = Color.Red
            e.CellElement.GradientStyle = Telerik.WinControls.GradientStyles.Solid

        Else
            e.CellElement.ResetValue(LightVisualElement.BackColorProperty, Telerik.WinControls.ValueResetFlags.Local)
            e.CellElement.ResetValue(LightVisualElement.ForeColorProperty, Telerik.WinControls.ValueResetFlags.Local)
            e.CellElement.ResetValue(LightVisualElement.GradientStyleProperty, Telerik.WinControls.ValueResetFlags.Local)

        End If
    End If
End Sub

I hope this will be useful. Let me know if you have additional questions.

Regards,
Dimitar
Progress Telerik

[Brandon]

My ListView is populated with data from a DataSet object.  The ListView isn't bound to the dataset. I loop through the dataset and create the items for the ListView.  Without cell formatting, the ListView is slightly laggy.  It doesn't scroll as smoothly as I think it should.  There's a small bit of hesitation that I can clearly see if I try to scroll quickly.

 

The entire ListView takes a dump when I add the CellFormatting code below:

Private Sub lvEquip_CellFormatting(sender As Object, e As ListViewCellFormattingEventArgs) 'Handles lvEquip.CellFormatting
    Dim cell As DetailListViewDataCellElement = TryCast(e.CellElement, DetailListViewDataCellElement)
    If cell IsNot Nothing Then

        If cell.Row("Col1").ToString() IsNot Nothing Then
            Dim DR As DataRow = cell.Row.Tag
            Dim C As Color
            Select Case e.CellElement.Data.Name

                Case "Col4" 'Status
                    Select Case GetFromRow(DR, EquipmentCI.Status)
                        Case "Resolved"
                            C = Color.Green
                        Case "UnResolved"
                            C = Color.Red
                        Case "Temporary Resolution"
                            C = Color.Orange
                    End Select
                    e.CellElement.ForeColor = C

                Case "Col5" 'Pump Stand Status
                    Dim ID As Integer = If(IsNumeric(GetFromRow(DR, EquipmentCI.PSStatus)), CInt(GetFromRow(DR, EquipmentCI.PSStatus)), 0)
                    Select Case DirectCast(ID, PSStatus)
                        Case PSStatus.PS
                            C = Color.Red
                        Case PSStatus.A
                            C = Color.Orange
                        Case PSStatus.R
                            C = Color.Green
                    End Select
                    e.CellElement.ForeColor = C

                Case "Col18" 'Last PM
                    Dim LPM As String = GetFromRow(DR, EquipmentCI.LastPM)
                    Dim EH As String = GetFromRow(DR, EquipmentCI.EngineHours)
                    If LPM.Length < 1 Then LPM = 0
                    If EH.Length < 1 Then EH = 0
                    Dim Cnt As Integer = CInt(EH) - CInt(LPM)
                    If Cnt >= LastPM_High Then
                        C = Color.Red
                    ElseIf Cnt >= LastPM_Medium Then
                        C = Color.Orange
                    Else
                        C = Color.Green
                    End If
                    e.CellElement.ForeColor = C

                Case "Col21" 'Sec Last PM
                    Dim LPM As String = GetFromRow(DR, EquipmentCI.SecLastPM)
                    Dim EH As String = GetFromRow(DR, EquipmentCI.SecEngineHours)
                    If LPM.Length < 1 Then LPM = 0
                    If EH.Length < 1 Then EH = 0
                    Dim Cnt As Integer = CInt(EH) - CInt(LPM)
                    If Cnt >= LastPM_High Then
                        C = Color.Red
                    ElseIf Cnt >= LastPM_Medium Then
                        C = Color.Orange
                    Else
                        C = Color.Green
                    End If
                    e.CellElement.ForeColor = C

                Case "Col23" 'Fed Insp
                    If GetFromRow(DR, EquipmentCI.FedInsp).Length > 0 Then
                        Dim DT As DateTime = FMDB(GetFromRow(DR, EquipmentCI.FedInsp), False)
                        Dim Diff As Long = DateDiff(DateInterval.Month, DT, DateTime.Now)
                        If Diff >= 13 Then
                            C = Color.Red
                        ElseIf Diff >= 6 Then
                            C = Color.Orange
                        Else
                            C = Color.Green
                        End If
                    End If
                    e.CellElement.ForeColor = C

                Case Else
                    e.CellElement.ResetValue(LightVisualElement.ForeColorProperty, ValueResetFlags.Local)

            End Select
        Else
            e.CellElement.ResetValue(LightVisualElement.ForeColorProperty, ValueResetFlags.Local)
        End If
    End If
End Sub

 

A few key ingredients here.

GetFromRow: Just returns Trim(DataRowObject.Item(ColumnIndex))

FMDB: Short for FormatDateBack converts a MySQL formatted DateTime string back to a DateTime object.  The boolean indicates whether I want to include the time.

 

Anyway, am I doing something wrong in the CellFormatting?

[Brandon]

Update: I thought that maybe the ListView was more efficient when used in Bound mode so I converted the ListView over to use a Bound collection.  I now get an even more laggy experience without the CellFormatting.

[Dimitar]

Hello Brandon,

I noticed that you have opened a ticket for this. We can continue to discuss this there.

Do not hesitate to contact us if you have other questions.

 

Regards,
Dimitar
Progress Telerik