Textbox binding to list won't update - wpf

Question

HI,
I have a list of coursesTaken with dates (returned by a nested class). Since I am not sure howmany courses the person took, I just bind it to textboxes and is working fine. The datacontext of the grid is the list itself so I assume whenever I make changes to the form, it is automatically sent back to the list and add it, but when it is time to save it in DB, the list won't change. I tried making the list as an observable collection and bind mode two way but still won't change. when I try to put Onpropertychange it says "Cannot acces a non static member of outer type via nested type..." What I want to do is whenever I type / add something to textbox, the list will add it as it's nth item so I can iterate and save it in DB.
is ther any other way to do this? please see code below. thanks!
#region class for binding purposes (nested class)
public class ListCon
{
public ObservableCollection<tblGALContinuingEducationHistory> EducList
{
get
{
return new ObservableCollection<tblGALContinuingEducationHistory>(contEducHstoryList);
}
}
}
#endregion
#region constructor
public ContinuingEducHistoryPopUp(tblAttorneyGalFileMaint currentGal)
{
contEducHstoryList = new ObservableCollection<tblGALContinuingEducationHistory>();
InitializeComponent();
if (currentGal != null)
{
CurrentGal = currentGal;
txtMemberName.Text = CurrentGal.FullName;
contEducHstoryList = new ObservableCollection<tblGALContinuingEducationHistory>(currentGal.tblGALContinuingEducationHistories.Count > 0 && currentGal.tblGALContinuingEducationHistories != null ? currentGal.tblGALContinuingEducationHistories : null);
}
this.DataContext = new ListCon();
}
#endregion
Now here's my xaml
<Grid Grid.Row="2" Grid.ColumnSpan="2" Name="grdEducForm">
<Grid.RowDefinitions>
<RowDefinition Height="25" />
<RowDefinition Height="25" />
<RowDefinition Height="25" />
<RowDefinition Height="25" />
<RowDefinition Height="25" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="2*" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<TextBox Text="{Binding Path=EducList[0].CourseTitle}" Grid.Column="0" Grid.Row="0" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[0].CertificateDate}" Grid.Column="1" Grid.Row="0" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[0].CertificateExpiration}" Grid.Column="2" Grid.Row="0" />
<TextBox Text="{Binding EducList[1].CourseTitle}" Grid.Column="0" Grid.Row="1" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[1].CertificateDate}" Grid.Column="1" Grid.Row="1" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[1].CertificateExpiration}" Grid.Column="2" Grid.Row="1" />
<TextBox Text="{Binding Path=EducList[2].CourseTitle}" Grid.Column="0" Grid.Row="2" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[2].CertificateDate}" Grid.Column="1" Grid.Row="2" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[2].CertificateExpiration}" x:Name="dpEnd3"
Grid.Column="2" Grid.Row="2" />
<TextBox Text="{Binding Path=EducList[3].CourseTitle, Mode=TwoWay}" Grid.Column="0" Grid.Row="3" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[3].CertificateDate, Mode=TwoWay}" Grid.Column="1"
Grid.Row="3" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[3].CertificateExpiration}" Grid.Column="2" Grid.Row="3" />
<TextBox Text="{Binding Path=EducList[4].CourseTitle}" Name="txtEducName5" Grid.Column="0" Grid.Row="4" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[4].CertificateDate}" x:Name="dpStart5" Grid.Column="1"
Grid.Row="4" />
<useable:MaskedDatePicker DateValue="{Binding Path=EducList[4].CertificateExpiration}" x:Name="dpEnd5"
Grid.Column="2" Grid.Row="4" />
</Grid>

Answer 1

In your ListCon property you always return a new collection this defeats the point of having an ObservableCollection at all, you should store it in a field like this:
//Initialize field in constructor
private readonly ObservableCollection<tblGALContinuingEducationHistory> _ListCon;
public ObservableCollection<tblGALContinuingEducationHistory> ListCon
{
get
{
return _ListCon;
}
}

Answer 2

EducList = new ObservableCollection<tblGALContinuingEducationHistory>(currentGal.tblGALContinuingEducationHistories.Count > 0 && currentGal.tblGALContinuingEducationHistories != null ? currentGal.tblGALContinuingEducationHistories : null);
int count = 0;
//5 is the maximum no of course an atty can take and save in this form
count = 5 - EducList.Count;
for (int i = 0; i < count; i++)
{
galContEdu = FileMaintenanceBusiness.Instance.Create<tblGALContinuingEducationHistory>();
galContEdu.AttorneyID = currentGal.AttorneyID;
EducList.Add(galContEdu);
}
then save only the ones that has data:
foreach (var item in EducList)
{
if(!string.IsNullOrEmpty(item.CourseTitle) || !string.IsNullOrWhiteSpace(item.CourseTitle))
FileMaintenanceBusiness.Instance.SaveChanges(item, true);
}