Rank 1
Hi!
I have created a custom server control which implements your data grid.
Everything works fine except that when I click the “delete” button it does not fire the “ItemCommand” event. It does go to the server however.
I have attached my code here so you can take a look.
Thank you in advance!
Imports System
Imports System.Web.UI.WebControls
Imports System.Web.UI
Imports Telerik.WebControls
Imports System.ComponentModel
<DefaultProperty(""), ToolboxData("<{0}:npaGeneralDataGrid runat=server></{0}:npaGeneralDataGrid>")> _
Public Class npaGeneralDataGrid
Inherits Global.Telerik.WebControls.RadGrid
Private _ShowColumnEmployeeNumber As Boolean = False
Private _ShowColumnDeleteNPA As Boolean = False
Private _iconDeleteNPA As String
Private _GridType As GridTypeEnum
'Private oUserProfile As NPABusinessServices.UserProfile
Private _dataGridOwner As String
#Region "Custom Properties"
Public Property GridType() As GridTypeEnum
Get
Return _GridType
End Get
Set(ByVal value As GridTypeEnum)
_GridType = value
End Set
End Property
Public Property ShowColumnEmployeeNumber() As Boolean
Get
Return _ShowColumnEmployeeNumber
End Get
Set(ByVal value As Boolean)
_ShowColumnEmployeeNumber = value
End Set
End Property
Public Property ShowColumnDeleteNPA() As Boolean
Get
Return _ShowColumnDeleteNPA
End Get
Set(ByVal value As Boolean)
_ShowColumnDeleteNPA = value
End Set
End Property
Public Property iconDeleteNPA() As String
Get
Return _iconDeleteNPA
End Get
Set(ByVal value As String)
_iconDeleteNPA = value
End Set
End Property
#End Region
#Region "Grid Type Enumeratior"
Public Enum GridTypeEnum As Integer
Drafts = 0
End Enum
#End Region
Public Sub New()
MyBase.New()
MyBase.AutoGenerateColumns = False
End Sub
Private Sub npaGeneralDataGrid_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
Dim oCol As GridColumn
oCol = New EmployeeNumber
oCol.HeaderText = "Emp No."
oCol.SortExpression = "LastName"
oCol.HeaderStyle.Width = Unit.Pixel(60)
oCol.HeaderStyle.HorizontalAlign = WebControls.HorizontalAlign.Left
oCol.ItemStyle.HorizontalAlign = WebControls.HorizontalAlign.Left
oCol.Visible = Me.ShowColumnEmployeeNumber
MyBase.MasterTableView.Columns.Add(oCol)
oCol = New DeleteNPA(_iconDeleteNPA)
MyBase.MasterTableView.Columns.Add(oCol)
oCol.HeaderText = ""
oCol.HeaderStyle.HorizontalAlign = WebControls.HorizontalAlign.Left
oCol.ItemStyle.HorizontalAlign = WebControls.HorizontalAlign.Left
oCol.Visible = Me.ShowColumnDeleteNPA
End Sub
Private Sub npaGeneralDataGrid_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
''data gets binded here - works beautifully
End Sub
Private Sub npaGeneralDataGrid_ItemCommand(ByVal source As Object, ByVal e As Telerik.WebControls.GridCommandEventArgs) Handles Me.ItemCommand
''this is never fired
Select Case e.CommandName.ToUpper()
Case "DELETE"
Case "DESELECT"
Case "PAGE"
End Select
End Sub
End Class
''class containing the column definition
Imports System
Imports System.Data
Imports System.Configuration
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls
Imports Telerik.WebControls
Public Class EmployeeNumber
Inherits GridTemplateColumn
Private Class ActualClass
Implements ITemplate
Public Column As EmployeeNumber = Nothing
Public Sub InstantiateIn(ByVal container As System.Web.UI.Control) Implements System.Web.UI.ITemplate.InstantiateIn
Dim oLabel As New Label
oLabel.ID = "lblEmployeeNumber"
container.Controls.Add(oLabel)
AddHandler oLabel.DataBinding, AddressOf BindObject
End Sub
Public Sub BindObject(ByVal sender As Object, ByVal e As EventArgs)
'Create a new instance of a Label.
Dim oLabel As Label = CType(sender, Label)
Dim container As GridDataItem = CType(oLabel.NamingContainer, GridDataItem)
'Bind the employee name to the label text
If Not IsDBNull(container.DataItem("EmployeeNumber")) Then
oLabel.Text = container.DataItem("EmployeeNumber")
End If
End Sub
End Class
Public Sub New()
Dim template As New ActualClass
template.Column = Me
Me.ItemTemplate = template
End Sub
End Class
Public Class LastUpdatedDate
Inherits GridTemplateColumn
Private Class ActualClass
Implements ITemplate
Public Column As LastUpdatedDate = Nothing
Public Sub InstantiateIn(ByVal container As System.Web.UI.Control) Implements System.Web.UI.ITemplate.InstantiateIn
Dim oLabel As New Label
oLabel.ID = "lblLastUpdatedDate"
container.Controls.Add(oLabel)
AddHandler oLabel.DataBinding, AddressOf BindObject
End Sub
Public Sub BindObject(ByVal sender As Object, ByVal e As EventArgs)
'Create a new instance of a Label.
Dim oLabel As Label = CType(sender, Label)
Dim container As GridDataItem = CType(oLabel.NamingContainer, GridDataItem)
'Bind the employee name to the label text
oLabel.Text = container.DataItem("LastUpdatedDate")
End Sub
End Class
Public Sub New()
Dim template As New ActualClass
template.Column = Me
Me.ItemTemplate = template
End Sub
End Class
Public Class DeleteNPA
Inherits GridTemplateColumn
Private Shared _IconPath As String
Private Class ActualClass
Implements ITemplate
Public Column As DeleteNPA = Nothing
Public Sub InstantiateIn(ByVal container As System.Web.UI.Control) Implements System.Web.UI.ITemplate.InstantiateIn
Dim oImageButton As New ImageButton
oImageButton.ID = "imgDeleteNPA"
oImageButton.ImageUrl = _IconPath
'oImageButton.CommandName = "delete"
container.Controls.Add(oImageButton)
AddHandler oImageButton.DataBinding, AddressOf BindObject
End Sub
Public Sub BindObject(ByVal sender As Object, ByVal e As EventArgs)
''Get the label's instance
Dim oImageButton As ImageButton = CType(sender, ImageButton)
Dim container As GridDataItem = CType(oImageButton.NamingContainer, GridDataItem)
''Bind the object's CommandArgument to the NPAID
oImageButton.CommandArgument = container.DataItem("NPAID")
oImageButton.CommandName = "delete"
End Sub
End Class
Public Sub New(ByVal iconPath As String)
Dim template As New ActualClass
template.Column = Me
Me.ItemTemplate = template
Me.AllowFiltering = False
_IconPath = iconPath
End Sub
End Class
5 Answers, 1 is accepted
Hello Alfredo,
I reviewed your code snippets and noticed that you add the DeleteNPA template column inside the Init handler first (before defining its properties):
| oCol = New DeleteNPA(_iconDeleteNPA) |
| MyBase.MasterTableView.Columns.Add(oCol) |
| oCol.HeaderText = "" |
| oCol.HeaderStyle.HorizontalAlign = WebControls.HorizontalAlign.Left |
| oCol.ItemStyle.HorizontalAlign = WebControls.HorizontalAlign.Left |
| oCol.Visible = Me.ShowColumnDeleteNPA |
This is in conflict with the concepts of dynamic RadGrid creation (entirely programmatically from the code-behind) listed here:
http://www.telerik.com/help/aspnet-ajax/grdprogrammaticcreation.html
I suggest you move the line which adds the column to the Columns collection as last in the code snippet as this will ensure that the viewstate of the column and the lifecycle of the controls in it will remain intact.
You may also define the CommandName="Delete" value for the image button (which is part of the template column) directly inside the InstantiateIn overridden method.
Kind regards,
the Telerik team
Instantly find answers to your questions on the new Telerik Support Portal.
Check out the tips for optimizing your support resource searches.
Rank 1
Sebastian,
Thank you for your reply.
I initially had the “add” column lines at the end of the code snippets for “deleteNPA”. I was just moving it around to see if the order affected the outcome… I was actually following a suggestion from the “Programmatic creation” article:
boundColumn = New GridBoundColumn()
tableViewOrders.Columns.Add(boundColumn)
boundColumn.DataField = "OrderDate"
boundColumn.HeaderText = "Date Ordered"
I had also defined the CommandName inside the InstantiateIn method. I just also moved it around to see if it produced another result.
Anyways, I have moved them back to their original position (the one suggested by you) but still not working.
I have previously built custom controls using your RadComboBox object and they all have worked flawlessly. It would be fantastic if I can get this issue resolved promptly. Is there any other thing that might be causing my code not to work properly?
Once again thank you for your help.
Alfredo
The method you depicted would be correct if you set the grid statically on the page and build its columns programmatically inside the OnLoad handler inside !Page.IsPostBack condition (see the help topic for reference).
I assume that in your case you create the entire control programmatically and generate its columns inside the OnInit handler. In this case you need to define the properties of the columns first and then add them to the Columns collection because the Init event is fired before LoadViewState in the page lifecycle.
Furthermore, can you verify that the viewstate of the grid (or this of the page/application which hosts it) is enabled in this case? This is required in order image buttons to trigger the event bubbling mechanism of the grid and subsequently fire its ItemCommand server event.
Kind regards,
Sebastian
the Telerik team
Instantly find answers to your questions on the new Telerik Support Portal.
Check out the tips for optimizing your support resource searches.
Rank 1
The Viewstate for both the page and the data grid should be enabled by default but I programmatically enabled them just in case.
Datagrid: MyBase.EnableViewState = True
Page: EnableViewState="true"
The ItemCommand is still not being fired. The call goes to the object after I hit the ImageButton. I have set up a break point in the custom control’s Load event that verifies the call is being made.
Alfredo
I conclude that your implementation follows the conventions for RadGrid programmatic creation inside OnInit from the documentation.
Is it possible for you to perform a quick test - extend the MS GridView control and wrap the same image button inside a template field which is build dynamically to see whether the OnRowCommand event of the GridView is fired as expected? If so, I suggest you post a simple demo which hosts both grids (RadGrid and MS GridView) attached to a formal support ticket. I will examine it in detail and will get back to you with more info on the subject.
Best regards,
Sebastian
the Telerik team
Instantly find answers to your questions on the new Telerik Support Portal.
Check out the tips for optimizing your support resource searches.