Binding to a DataView

[Chris]

Hi,

I am try to bind a RadGridView to DataView because of the Notify events that are already available. I am using the WPF MVVM architecture therefore the Grid is defined in the XAML and the DataView in my presentation Layer. I have a background worker that will populate the table in the DataView and I was hoping the RadGridView would then update accordingly. I am not too sure why it is not working or whether it can work in this context. Please see the code snippet below.

 

View:

<telerikGrid:RadGridView x:Name="activeSessionsGrid" AutoGenerateColumns="True" ItemsSource="{Binding Path=ActiveSessions}"

</telerikGrid:RadGridView> 

Presentation Model:

private DataView _activeSessions;

 

public DataView ActiveSessions

{

     get

     {

        return this._activeSessions;

     }           

}

private void GenereateTableStructure ( )

{

this._activeSessions = new DataView ( ); 

this._activeSessions.Table = new DataTable ( "Sessions" );

this._activeSessions.Table.Columns.Add ( "ID" );

this._activeSessions.Table.Columns.Add ( "Name" );

this._activeSessions.Table.Columns.Add ( "Surname" );

this._activeSessions.Table.Columns.Add ( "Designation" );

this._activeSessions.Table.Columns.Add ( "User Name" );

this._activeSessions.Table.Columns.Add ( "Email Address" );

this._activeSessions.Table.Columns.Add ( "Last Access Time" );
}

//BackgroundWorker that populates the _activeSessions table

 

Thanks in advance for your assistance.

[Vlad]

Hi,

 You will need to raise manually PropertyChanged for this property (ActiveSessions).

Greetings,
Vlad
the Telerik team

[Chris]

Hi Vlad,

Please excuse my ignorant but I have made the following changes but to no avail.

 

public DataView ActiveSessions

{

   get

   {

     return this._activeSessions;

   }

   set

   {               

     this._activeSessions = value;

     PropertyChanged = new PropertyChangedEventHandler ( this.Notifychanges );

   }

}

 

 

private void Notifychanges ( object sender, PropertyChangedEventArgs e )

{

   if ( e.PropertyName != null )

       PropertyChanged ( this, new PropertyChangedEventArgs ( e.PropertyName ) );

}

 

public event PropertyChangedEventHandler PropertyChanged;

[Vlad]

Hi,

 Are you still using the field directly? Here is the code from your previous post:

private void GenereateTableStructure ( )

{

this._activeSessions = new DataView ( ); 

...

You will need also just to raise the event not to create new event handler in the property setter. 

Greetings,
Vlad
the Telerik team

[Chris]

Hi,

Yes i am but the Property changed event is null as it has not been instantiated. I have included the entire class below.

public class ActiveSessionsPresentationModel:IActiveSessionsPresentationModel,INotifyPropertyChanged
    {
        private IShellController controller;
        private IActiveSessionsView view;
        private IDataBrokerService dbProxy;
        private BackgroundWorker worker;
        private DataView _activeSessions;

        public ActiveSessionsPresentationModel ( IShellController controller, IActiveSessionsView view, IDataBrokerService dbProxy )
        {
            this.controller = controller;
            this.view = view;
            this.dbProxy = dbProxy;
        }

        public IActiveSessionsView View
        {
            get
            {
                return this.view;
            }
        }

        public DataView ActiveSessions
        {
            get
            {
                return this._activeSessions;
            }
            set
            {
                this._activeSessions = value;
                this.Notifychanges ( this, new PropertyChangedEventArgs ( "ActiveSessions" ) );
            }
        }

        public void DisplayActiveSessions ( )
        {
            ActiveSessionsResponse response = new ActiveSessionsResponse ( );
            response = this.dbProxy.ListActiveSessions ( );

            GenereateTableStructure ( );

            object [ ] obj = new object [ 1 ];
            obj [ 0 ] = response.ActiveSessions;

            this.worker = new BackgroundWorker ( );
            this.worker.DoWork += new DoWorkEventHandler ( worker_DoWork );
            this.worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler ( worker_RunWorkerCompleted );
            this.worker.RunWorkerAsync ( obj );
        }

        private void GenereateTableStructure ( )
        {
            this._activeSessions = new DataView ( );
            this._activeSessions.Table = new DataTable ( "Sessions" );
            this._activeSessions.Table.Columns.Add ( "ID" );
            this._activeSessions.Table.Columns.Add ( "Name" );
            this._activeSessions.Table.Columns.Add ( "Surname" );
            this._activeSessions.Table.Columns.Add ( "Designation" );
            this._activeSessions.Table.Columns.Add ( "User Name" );
            this._activeSessions.Table.Columns.Add ( "Email Address" );
            this._activeSessions.Table.Columns.Add ( "Last Access Time" );
        }

        private void worker_RunWorkerCompleted ( object sender, RunWorkerCompletedEventArgs e )
        {
            this.worker.Dispose ( );
        }

        private void worker_DoWork ( object sender, DoWorkEventArgs e )
        {
            object [ ] obj = (object []) e.Argument;
            Dictionary<Guid, DateTime> sessions = ( Dictionary<Guid, DateTime> ) obj [ 0 ];

            Parallel.ForEach ( sessions, pair =>
            {
                PersonResponse response = this.dbProxy.SelectPerson ( new PersonIDRequest ( )
                {
                    ID = pair.Key
                } );

                if ( response != null )
                {
                    _activeSessions.Table.NewRow ( );
                    DataRow row = _activeSessions.Table.NewRow ( );
                    row [ "ID" ] = pair.Key;
                    row [ "Name" ] = AccessControl.GetADUserFirstName ( response.Person.UserName );
                    row [ "Surname" ] = AccessControl.GetADUserSurname ( response.Person.UserName );
                    row [ "Designation" ] = AccessControl.GetADUserDesignation ( response.Person.UserName );
                    row [ "User Name" ] = response.Person.UserName;
                    row [ "Email Address" ] = AccessControl.GetADUserEmailAddress ( response.Person.UserName );
                    row [ "Last Access Time" ] = pair.Value;
                    _activeSessions.Table.Rows.Add ( row );
                    ActiveSessions = _activeSessions;

                }
                else
                {
                    _activeSessions.Table.NewRow ( );
                    DataRow row = _activeSessions.Table.NewRow ( );
                    row [ "ID" ] = pair.Key;
                    row [ "Name" ] = string.Empty;
                    row [ "Surname" ] = string.Empty;
                    row [ "Designation" ] = string.Empty;
                    row [ "User Name" ] = string.Empty;
                    row [ "Email Address" ] = string.Empty;
                    row [ "Last Access Time" ] = pair.Value;
                    _activeSessions.Table.Rows.Add ( row );
                }
            } );
        }

        #region INotifyPropertyChanged Members

        private void Notifychanges ( object sender, PropertyChangedEventArgs e )
        {
            if ( e.PropertyName != null )

                PropertyChanged ( this, new PropertyChangedEventArgs ( e.PropertyName ) );
        }

        public event PropertyChangedEventHandler PropertyChanged;

        #endregion
    }

    public interface IActiveSessionsPresentationModel
    {
        IActiveSessionsView View
        {
            get;
        }
        void DisplayActiveSessions ( );
        DataView ActiveSessions
        {
            get;
        }
    }

[Chris]

Hi,

Would i not also need to change my binding to

ItemsSource="{Binding Path=ActiveSessions, Mode=TwoWay}"