[CLOSED] GridPanel disappear code-behind

[mis@adphk.com]

When I refresh gridpanel it will disappear

case 1: directclick refresh and wait around 1 second -> gridpanel is work fine
case 2: directclick refresh and wait less then 1 second -> gridpanel is disappear and never show again until refresh browser

I am using List Of <T> to fill in the Store and call gridpanel.Render

Public Sub FillLstOfDataToGridPanel(Of t)(ByVal objLstOf As List(Of t), Optional ByVal strShowHideColNameList As String = Nothing, Optional ByVal strIDProperty As String = Nothing, Optional blnTIsShowFIsHide As Boolean = False, Optional strColumnAlias As String = Nothing )
        Dim objLstOfProp As List(Of clsNameAndProperty)
        Dim objModel As New Ext.Net.Model
        Dim objExtCol As Ext.Net.Column
        Dim objExtDateCol As Ext.Net.DateColumn

        Dim i As Integer
        Dim blnShowIt As Boolean
        Dim strSplit() As String

        Dim strText As String
        Dim strAlias() As String


        If objLstOf.Count < 1 Then
            mExtNetStore.Reader.Clear()
            objModel.Fields.Clear()
            mExtNetGridPanel.RemoveAllColumns()
            Exit Sub
        End If


        objLstOfProp = getListOfProperty(objLstOf(0))
        mExtNetStore.DataSource = objLstOf
        mExtNetGridPanel.RemoveAllColumns()
        objModel = FillLstOfObjectToModel(objLstOfProp, strIDProperty)

        If mExtNetGridPanel.StoreID Is Nothing OrElse mExtNetGridPanel.StoreID.Trim = "" Then
            mExtNetGridPanel.StoreID = mExtNetStore.ID
        End If
        strAlias = Split(strColumnAlias, ",")
        strSplit = Split(strShowHideColNameList, ",")
        For i = 0 To objLstOfProp.Count - 1
            blnShowIt = False
            If strShowHideColNameList Is Nothing OrElse strShowHideColNameList.Trim = "" Then
                blnShowIt = True
            Else
                Dim query = From obj As String In strSplit Where obj = objLstOfProp(i).Name.Trim

                If query.Count > 0 Then
                    If blnTIsShowFIsHide = True Then
                        blnShowIt = True
                    Else
                        blnShowIt = False
                    End If
                End If
            End If
            Dim strPropertyName As String
            strPropertyName = objLstOfProp(i).Name
            strText = ""
            If strColumnAlias Is Nothing OrElse strColumnAlias.Trim = "" Then
                strText = strPropertyName
            Else
                strText = strPropertyName
                Dim CheckEqu As Char() = New Char() {"="}
                Dim AliasQuery = From objAlias As String In strAlias Where objAlias.Split("=")(0).Trim = strPropertyName.Trim

                If AliasQuery.Count > 0 Then
                    For Each objResult In AliasQuery
                        strText = objResult.ToString.Split("=")(1)
                    Next
                End If
            End If

            If blnShowIt = True Then
                If objLstOfProp(i).ExtNetModelType = Ext.Net.ModelFieldType.Date Then
                    objExtDateCol = New Ext.Net.DateColumn
                    objExtDateCol.Text = strText        ''objLstOfProp(i).Name
                    objExtDateCol.DataIndex = objLstOfProp(i).Name
                    objExtDateCol.Format = "yyyy/MM/dd"
                    mExtNetGridPanel.AddColumn(objExtDateCol)
                Else
                    objExtCol = New Ext.Net.Column
                    objExtCol.Text = strText        ''objLstOfProp(i).Name
                    objExtCol.DataIndex = objLstOfProp(i).Name
                    mExtNetGridPanel.AddColumn(objExtCol)
                End If
            End If
        Next
        mExtNetStore.Model.Clear()
        mExtNetStore.Model.Add(objModel)
        mExtNetStore.RebuildMeta()
        mExtNetStore.DataBind()
        mExtNetGridPanel.DataBind()
        mExtNetGridPanel.Render()
    End Sub