DataGrid Grouping

Hi,

I am trying to group items in a datagrid based on a particular property, I am not able to see the group header text. I have given below the Xaml part, ViewModel & Model. Looking forward for help.

Regards,

Ramakrishna

Xaml code:

<DataGrid ItemsSource="{Binding GroupView}" AutoGenerateColumns="False">
                <DataGrid.GroupStyle>
                    <GroupStyle>
                        <GroupStyle.HeaderTemplate>
                            <DataTemplate>
                                <StackPanel>
                                    <TextBlock Text="{Binding Path=Subject}" />
                                </StackPanel>
                            </DataTemplate>
                        </GroupStyle.HeaderTemplate>
                        <GroupStyle.ContainerStyle>
                            <Style TargetType="{x:Type GroupItem}">
                                <Setter Property="Template">
                                    <Setter.Value>
                                        <ControlTemplate TargetType="{x:Type GroupItem}">
                                           <Expander>
                                               <Expander.Header>
                                                   <StackPanel Orientation="Horizontal">
                                                       <TextBlock Text="{Binding Path=Subject}" />
                                                   </StackPanel>
                                               </Expander.Header>
                                               <ItemsPresenter />
                                           </Expander>
                                        </ControlTemplate>
                                    </Setter.Value>
                                </Setter>
                            </Style>
                        </GroupStyle.ContainerStyle>
                    </GroupStyle>
                </DataGrid.GroupStyle>

                <DataGrid.Columns>
                    <DataGridCheckBoxColumn Header="File" Binding="{Binding IsChecked}"/>
                    <DataGridTextColumn Header="Attachment Name" Binding="{Binding OriginalName}"/>
                    <DataGridTextColumn Header="Filing Attachment Name" Binding="{Binding FinalName}"/>
                    <DataGridTextColumn Header="Location" Binding="{Binding Location}"/>
                    <DataGridTextColumn Header="Subject" Binding="{Binding Subject}"/>
                </DataGrid.Columns>
            </DataGrid>

ViewModel Code:

 public class AttachmentViewModel : INotifyPropertyChanged
    {
       Private ListCollectionView view;

        public AttachmentViewModel()
        {
            ObservableCollection<AttachmentItem> items = new ObservableCollection<AttachmentItem>();

            AttachmentItem item = new AttachmentItem(true, @"C:\Users\ram.devarakonda\Desktop\Me", "Me-14-05-2013", @"C:\Users\ram.devarakonda\Desktop", "Mysubject");
            AttachmentItem item1 = new AttachmentItem(false, @"C:\Users\ram.devarakonda\Desktop\He", "He-14-05-2013", @"C:\Users\ram.devarakonda\Desktop", "HeySubject");

            items.Add(item);
            items.Add(item1);

            GroupView = new ListCollectionView(items);
            GroupView.GroupDescriptions.Add(new PropertyGroupDescription("Subject"));
        }


        public ListCollectionView GroupView
        {
            get
            {
                return view;
            }

            set
            {
                this.view = value;
                this.OnPropertyChanged("GroupView");
            }
        }
    }

Model Code:

public class AttachmentItem : INotifyPropertyChanged
    {
        private bool ischecked;
        private string subject;
        private string originalName;
        private string finalName;
        private string location;

        public AttachmentItem(bool ischecked, string originalName, string finalName, string location, string subject)
        {
            this.Ischecked= ischecked;
            this.Subject = subject;
            this.OriginalName= originalName;
            this.FinalName= finalName;
            this.Location = location;
        }

        public bool Ischecked
        {
            get
            {
                return this.ischecked;
            }

            set
            {
                this.ischecked= value;
                this.OnPropertyChanged("Ischecked");
            }
        }

        public string Subject
        {
            get
            {
                return this.subject;
            }

            set
            {
                this.subject = value;
                this.OnPropertyChanged("Subject");
            }
        }

        public string OriginalName
        {
            get
            {
                return this.originalName;
            }

            set
            {
                this.originalName= value;
                this.OnPropertyChanged("OriginalName");
            }
        }


        public string FinalName
        {
            get
            {
                return this.finalName;
            }

            set
            {
                this.finalName= value;
                this.OnPropertyChanged("FinalName");
            }
        }

        public string Location
        {
            get
            {
                return this.location;
            }

            set
            {
                this.location = value;
                this.OnPropertyChanged("Location");
            }
        }

    }

Ramakrishna