To Use Telerik RadDataPager in Silverlight (Issue After Rebinding data) - xaml

Question

I am using MVVM framework. My question is that i am binding PagedCollectionView to radgridview and using raddatapager i want to do paging. As i am new to this can anybody tell me where i am going wrong. Also there is one problem while fetching record this works fine for 800 records but it didn't work for records above 1000(web service code is attached).
In Web service i am using this function to get list:
public List<GetStudents> GetStudentsListForUpdate(int schoolId, int academicYearId)
{
return new DbHelper().Find(StudentAdmissionCommands.GetStudentsListForUpdate(schoolId, academicYearId), new GenericObjectBuilder<GetStudents>());
}
![It works first time when page is loaded as snapshot is attached][1]
In ViewModel I defined Pagedcollection view like this:
PagedCollectionView pcv;
public PagedCollectionView Pcv
{
get { return pcv; }
set { pcv = value; OnPropertyChanged("Pcv"); }
}
//This function written to get student's list
public void GetStud()
{
Studlist.Clear();
RootVisualHelper.SetBusy(true);
StudentAdmissionServiceClient client = new StudentAdmissionServiceClient();
client.GetStudentsListForUpdateCompleted += (Cs, Ea) =>
{
if (Ea.Error == null)
{
RootVisualHelper.SetBusy(false);
if (Ea.Result.ToList().Count == 0)
{
EmptyMessageVisibility = "Visible";
}
else
{
EmptyMessageVisibility = "Collapsed";
foreach (var item in Ea.Result)
{
Studlist.Add(item);
}
Pcv = new PagedCollectionView(Studlist);
Pcv.GroupDescriptions.Clear();
Pcv.GroupDescriptions.Add(new PropertyGroupDescription("AllocatedClass"));
}
}
};
client.GetStudentsListForUpdateAsync(SchoolIdLog, AcademicYearId);
}
In Xaml, RadGridView binding:
<telerik:RadGridView ItemsSource="{Binding Pcv}" SelectedItem="{Binding SelectedStudentList,Mode=TwoWay}"
telerik:StyleManager.Theme="{Binding Theme,Mode=TwoWay}"
helpers:CustomFilterBehavior.TextBox="{Binding ElementName=textBoxFilterValue}"
ShowColumnFooters="True" ShowGroupPanel="False"
AutoGenerateColumns="False" IsReadOnly="True" Grid.Row="3"
Grid.ColumnSpan="2" x:Name="RadGridView1"
CanUserFreezeColumns="False" GroupRenderMode="Flat"
RowIndicatorVisibility="Collapsed">
<interactivity:Interaction.Triggers>
<interactivity:EventTrigger EventName="RowActivated">
<shared:EventToCommandTrigger Command="{Binding UpdateStudentCommand}" />
</interactivity:EventTrigger>
</interactivity:Interaction.Triggers>
<telerik:RadGridView.Columns>
<telerik:GridViewDataColumn DataMemberBinding="{Binding StudentRollNo}" Header="Student Code" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding StudentRegNo}" Header="Reg No." />
<telerik:GridViewDataColumn DataMemberBinding="{Binding StudentEsisNo}" Header="Esis No." />
<telerik:GridViewDataColumn DataMemberBinding="{Binding StudentName}" Header="Student Name" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding UserName}" Header="User Name" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding AllocatedClass}" Header="Class" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding Gender}" Header="Gender" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding DateOfBirth,StringFormat=dd/MM/yyyy}"
Header="Date Of Birth" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding ParentName}" Header="Parent Name" />
<telerik:GridViewDataColumn DataMemberBinding="{Binding ParentMobile}" Header="Father Mob. No." />
<telerik:GridViewDataColumn DataMemberBinding="{Binding MotherMobile1}" Header="Mother Mob. No." />
<telerik:GridViewDataColumn DataMemberBinding="{Binding StudentType}" Header="Student Type" />
</telerik:RadGridView.Columns>
</telerik:RadGridView>
<telerik:RadDataPager PageSize="100" Grid.Row="4"
FontSize="12" Margin="0,-1,0,0"
Source="{Binding Items, ElementName=RadGridView1}"
IsTotalItemCountFixed="false"
DisplayMode="FirstLastPreviousNextNumeric, Text" />
Whether I have to handle events of pagedcollection view? If so how to handle in MVVM Pattern?