hiding rows based on info from collection

[Keith Stephens]

I currently have a collection that I bind to a tabcontrol and on the tab control are grids that get bound to items in the collection.
Everything as of now work just fine.  Now I need to be able to populate the tabs based on some date that we have.

Since I already have everything I need and the page is running fine.
I thought I would put a checkbox on the page then if the box is checked or unchecked I could do some linq on the collection and then just bind the tab control to a new collection. 


Here is what I am trying to do, this comes from a wcf proxy call

    void proxy_GetAgtAgreeFromPortCompleted(object sender, AgtAgreeFrm.NoteSVC.GetAgtAgreeFromPortCompletedEventArgs e)
        {

            AgreementList = e.Result;
            if (Convert.ToBoolean(chkHistory.IsChecked))
            {
                var query = from alist in AgreementList
                            where Convert.ToDateTime(alist.EndDate) <= DateTime.Now.Date
                            select alist;



                //tabControl1.ItemsSource = query; //AgreementList;
            }
            else
            {
                var query = from alist in AgreementList
                            where Convert.ToDateTime(alist.EndDate) > DateTime.Now.Date
                            || Convert.ToDateTime(alist.BeginDate) > DateTime.Now.Date
                            select alist;

                //tabControl1.ItemsSource = query;
            }

            tabControl1.ItemsSource=query

            //tabControl1.ItemsSource = AgreementList;



            //AANoteBody = //Note.NoteBodyLines;
            //NoteBodyLines.Add(new NoteSVC.TshipNoteBody());
            //grdNoteBody.ItemsSource = NoteBodyLines;

            //List<NoteSVC.AANote> Notes = new List<NoteSVC.AANote>();
            //Notes = Agreement.Note;

            //ObservableCollection<NoteSVC.AANote> NotesNotes = Notes[0].;

            //cboPorts.Items.Clear();
            //cboPorts.ItemsSource = PortList;

            //string x = AgreementList[0].Notes[0].Lines[0].ToString();
           //this.gdvNotes.ItemsSource=;

            //public ObservableCollection<NoteSVC.TshipNoteBody> NoteBodyLines;

            //List<NoteSVC.AANote> Notes = new List<NoteSVC.AANote>();
            //Notes = AgreementList[0].Notes;

            //NoteNoteBodyLines = Note.NoteBodyLines;
            //NoteBodyLines.Add(new NoteSVC.TshipNoteBody());
            //grdNoteBody.ItemsSource = NoteBodyLines;

        }