How do I set up my silverlight app to pull data from a sharepoint list based on user inputs?

Posted on 2010-09-07
Last Modified: 2013-11-12
I have a silverlight app that I have hosted on a SharePoint 2010 site. The application pulls data from various lists on the site according to user inputs. At first, everything works fine. However, once the user tries to pull the data again based on a new criteria (but using the same listcollection) I get the error below...

Webpage error details

Message: Unhandled Error in Silverlight Application The collection has not been initialized. It has not been requested or the request has not been executed. It may need to be explicitly requested.   at Microsoft.SharePoint.Client.ClientObjectCollection`1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>d__0.MoveNext()
   at POSS.MainPage.BindGetProjectData()
Line: 1
Char: 1
Code: 0

I think it has to do with the fact that I'm using the same list collection over and over again depending on the subject area, but I don't know of another way to do it. Any ideas? I've attached some of my code. "GetThisProject()" method is called when the user choses a new project.
Partial Public Class MainPage

Inherits UserControl

Private _TheseIssues As ListItemCollection

Private context As ClientContext = New ClientContext(ApplicationContext.Current.Url)

Private oWebsite As Web = context.Web

Private spl_Portfolio As List = context.Web.Lists.GetByTitle("Portfolio")

Public Sub New()


End Sub

Private Sub GetThisProject()

        Me.myProgressBar.Visibility = Windows.Visibility.Visible

        Me.myProgressText.Visibility = Windows.Visibility.Visible

        'Get List of User's Projects -------------------------------------------------------------------------------------------


        Dim query As CamlQuery = New CamlQuery()

        Dim camlQueryXml As String = "<View><Query><Where><Eq><FieldRef Name=""Title"" /><Value Type='Text'>" + ChosenProject + "</Value></Eq></Where></Query><ViewFields>" + _

            "<FieldRef Name=""Title"" /><FieldRef Name=""Project_x0020_No"" /><FieldRef Name=""L3_x0020_Organization"" /><FieldRef Name=""L3_x0020_Manager"" /><FieldRef Name=""L4_x0020_Manager"" /><FieldRef Name=""Project_x0020_Status"" /><FieldRef Name=""Project_x0020_Condition"" /><FieldRef Name=""Project_x0020_Phase"" /><FieldRef Name=""Project_x0020_Manager"" /><FieldRef Name=""Top_x0020_200"" /><FieldRef Name=""CBA_x0020_Status"" />" + _

            "<FieldRef Name=""Forecasted_x0020_Finish_x0020_Qu"" /><FieldRef Name=""Solution_x0020_Short_x0020_Descr"" /><FieldRef Name=""Issues"" /><FieldRef Name=""Planning_x0020_State"" /><FieldRef Name=""Last_x0020_Updated"" /><FieldRef Name=""Planned_x0020_Completion_x0020_Q"" /><FieldRef Name=""Portfolio_x0020_Project_x0020_Ty"" /><FieldRef Name=""Innovation_x0020_Priority_x0020_"" /><FieldRef Name=""Reason_x0020_Late"" /><FieldRef Name=""Business_x0020_or_x0020_IT"" /><FieldRef Name=""IT_x0020_Innovation_x0020_Priori"" /><FieldRef Name=""Ec_x0020_Manager_x0020_Priority_"" /><FieldRef Name=""Domain_x0020_Council_x0020_Ranki"" /><FieldRef Name=""Sizing_x0020_Tier"" /><FieldRef Name=""Expected_x0020_Start_x0020_Perio"" /><FieldRef Name=""Expected_x0020_Finish_x0020_Peri"" /><FieldRef Name=""Planning_x0020_Phase_x0020_Basel"" />" + _

            "<FieldRef Name=""Planning_x0020_Phase_x0020_Basel0"" /><FieldRef Name=""Development_x0020_Phase_x0020_Ba"" /><FieldRef Name=""Development_x0020_Phase_x0020_Ba0"" /><FieldRef Name=""Warranty_x0020_Phase_x0020_Basel"" /><FieldRef Name=""Warranty_x0020_Phase_x0020_Basel0"" /><FieldRef Name=""Planning_x0020_Phase_x0020_Actua"" /><FieldRef Name=""Planning_x0020_Phase_x0020_Actua0"" /><FieldRef Name=""Development_x0020_Phase_x0020_Ac"" /><FieldRef Name=""Development_x0020_Phase_x0020_Ac0"" /><FieldRef Name=""Warranty_x0020_Phase_x0020_Actua"" /><FieldRef Name=""Warranty_x0020_Phase_x0020_Actua0"" /><FieldRef Name=""Current_x0020_Forecast_x0020_Fin"" /><FieldRef Name=""Planned_x0020_IT_x0020_Costs"" /><FieldRef Name=""Development_x0020_Forecast_x0020"" /><FieldRef Name=""Project_x0020_Structure_x0020_Ty"" /><FieldRef Name=""Summary_x0020_Phase"" /><FieldRef Name=""Current_x0020_FY_x0020_Above_x00"" /><FieldRef Name=""Data_x0020_Date"" />" + _

            "<FieldRef Name=""Accomplishments"" /><FieldRef Name=""Next_x0020_Steps"" /><FieldRef Name=""Color_PBFD"" /><FieldRef Name=""Color_PAFD"" /><FieldRef Name=""Color_DBFD"" /><FieldRef Name=""Color_DFFD"" /><FieldRef Name=""Color_DAFD"" /><FieldRef Name=""Color_WBFD"" /><FieldRef Name=""Color_CFFD"" /><FieldRef Name=""Color_WAFD"" /><FieldRef Name=""Color_CBAStatus"" /><FieldRef Name=""Color_OTD"" /><FieldRef Name=""Business_x0020_PM"" /><FieldRef Name=""IT_x0020_Manager"" /><FieldRef Name=""Status_x0020_Summary"" /></ViewFields></View>"

        query.ViewXml = camlQueryXml

        _ThisProject = spl_Portfolio.GetItems(query)


        context.ExecuteQueryAsync(New ClientRequestSucceededEventHandler(AddressOf OnGetProjectRequestSucceeded), Nothing)

    End Sub

Private Sub OnGetProjectRequestSucceeded(ByVal sender As Object, ByVal args As ClientRequestSucceededEventArgs)

        Dispatcher.BeginInvoke(New Action(AddressOf BindGetProjectData))

    End Sub

Private Sub BindGetProjectData()

        Dim projects As List(Of Project) = New List(Of Project)()

        Dim pdates As List(Of ProjectDates) = New List(Of ProjectDates)()

        Dim nextTrigger As Integer = 0

        Dim nextproject As String = Nothing


        For Each li As ListItem In _ThisProject ' The error occurs around here

            ps_ProjectNo.Text = li("Project_x0020_No")

            ps_ProjectName.Text = li("Title")

            ps_ProjectCondition.Text = li("Project_x0020_Condition")

            ps_ProjectPhase.Text = li("Project_x0020_Phase")

            ps_Status.Text = li("Project_x0020_Status")

            ps_ITManager.Text = li("IT_x0020_Manager")

            ps_ITPM.Text = li("Project_x0020_Manager")

            ps_BusinessPM.Text = li("Business_x0020_PM")

            ps_SSD.Text = li("Solution_x0020_Short_x0020_Descr")

            ps_Accomplishments.Text = li("Accomplishments")

            ps_NextSteps.Text = li("Next_x0020_Steps")

            If li("Planning_x0020_Phase_x0020_Basel0") IsNot Nothing Then ps_PBFD.Text = li("Planning_x0020_Phase_x0020_Basel0").ToShortDateString()

            If li("Development_x0020_Phase_x0020_Ba0") IsNot Nothing Then ps_DBFD.Text = li("Development_x0020_Phase_x0020_Ba0").ToShortDateString()

            If li("Development_x0020_Forecast_x0020") IsNot Nothing Then ps_DFFD.Text = li("Development_x0020_Forecast_x0020").ToShortDateString()

            If li("Warranty_x0020_Phase_x0020_Basel0") IsNot Nothing Then ps_WBFD.Text = li("Warranty_x0020_Phase_x0020_Basel0").ToShortDateString()

            If li("Planning_x0020_Phase_x0020_Actua0") IsNot Nothing Then ps_PAFD.Text = li("Planning_x0020_Phase_x0020_Actua0").ToShortDateString()

            If li("Development_x0020_Phase_x0020_Ac0") IsNot Nothing Then ps_DAFD.Text = li("Development_x0020_Phase_x0020_Ac0").ToShortDateString()

            If li("Warranty_x0020_Phase_x0020_Actua0") IsNot Nothing Then ps_WAFD.Text = li("Warranty_x0020_Phase_x0020_Actua0").ToShortDateString()

            If li("Current_x0020_Forecast_x0020_Fin") IsNot Nothing Then ps_CFFD.Text = li("Current_x0020_Forecast_x0020_Fin").ToShortDateString()

            For Each mi As AgMenuItem In agm_Projects.Items

                nextTrigger = 0

                For Each miproj As AgMenuItem In mi.Items

                    If nextTrigger = 1 Then

                        nextproject = miproj.Header

                        Exit For

                    End If

                    If miproj.Header <> li("Title") Then

                        prvprj.Text = miproj.Header


                        miproj.Header = li("Title")

                        nextTrigger = 1

                    End If

                Next miproj

                If nextTrigger = 1 Then

                    nxtprj.Text = nextproject

                    Exit For

                End If

            Next mi

            ps_ColorProjectCondition.Background = PConditionSwatch(li("Project_x0020_Condition"))

            ps_ColorPBFD.Fill = PConditionSwatch(li("Color_PBFD"))

            ps_ColorPAFD.Fill = PConditionSwatch(li("Color_PAFD"))

            ps_ColorDBFD.Fill = PConditionSwatch(li("Color_DBFD"))

            ps_ColorDFFD.Fill = PConditionSwatch(li("Color_DFFD"))

            ps_ColorDAFD.Fill = PConditionSwatch(li("Color_DAFD"))

            ps_ColorWBFD.Fill = PConditionSwatch(li("Color_WBFD"))

            ps_ColorCFFD.Fill = PConditionSwatch(li("Color_CFFD"))

            ps_ColorWAFD.Fill = PConditionSwatch(li("Color_WAFD"))

            ps_ColorCBA.Fill = PConditionSwatch(li("Color_CBAStatus"))

            ps_ColorOTD.Fill = PConditionSwatch(li("Color_OTD"))

            If li("Project_x0020_Condition") = "Yellow" Or li("Project_x0020_Condition") = "Red" Then

                ps_opt_StatusSum.Visibility = Windows.Visibility.Visible

                ps_StatusSummary.Visibility = Windows.Visibility.Visible

                ps_grd_Accomplishments.Margin = New Thickness(0, 8, 0, 0)

                ps_StatusSummary.Text = li("Status_x0020_Summary")


                ps_opt_StatusSum.Visibility = Windows.Visibility.Collapsed

                ps_StatusSummary.Visibility = Windows.Visibility.Collapsed

                ps_grd_Accomplishments.Margin = New Thickness(0, 0, 0, 0)

            End If


        For Each pj As Project In projects

            nxtprj.text = projects(pj.ProjectListID + 1).PName




        Me.myProgressText.Text = "Done!"

        Me.myProgressText.Visibility = Windows.Visibility.Collapsed

        Me.myProgressBar.Visibility = Windows.Visibility.Collapsed

        Me.myProgressText.Text = "Loading..."

    End Sub

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Question by:AaronHPackard
LVL 29

Accepted Solution

Gautham Janardhan earned 500 total points
ID: 33668443
you need to make a call to context.Web.Retrieve(WebPropertyNames.Id,WebPropertyNames.Title) before calling the ExecuteQueryAsync.
LVL 17

Expert Comment

ID: 36123445
This question has been classified as abandoned and is closed as part of the Cleanup Program. See the recommendation for more details.

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