Problem with ObservableCollection and INotifyPropertyChanged in MVVM

Answer 1

Needs more code. How do you bind? What type is ObservableCollection of? Are you sure you are notyfing in class that is value of ObservableColletion?

Edit: Also change title of your question. This is little ambiguous and not really problem of your question.

Answer 2

Have you tried something like this...

private IEnumerable<DataPoint> _DataPoints;
public IEnumerable<DataPoint> DataPoints
{
    get
    {
        return _DataPoints;
    }

    set
    {
        if (_DataPoints != value)
        {
            _DataPoints = value;
            this.OnPropertyChanged("DataPoints");
        }
    }
}

Then whenever you modify ANY point within the DataPoints collection, you raise a property change event for the entire DataPoints set

    /// <summary>
    /// Raised when a property on this object has a new value.
    /// </summary>
    public event PropertyChangedEventHandler PropertyChanged;

    /// <summary>
    /// Raises this object's PropertyChanged event.
    /// </summary>
    /// <param name="propertyName">The property that has a new value.</param>
    protected virtual void OnPropertyChanged(string propertyName)
    {
        //this.VerifyPropertyName(propertyName);

        PropertyChangedEventHandler handler = this.PropertyChanged;
        if (handler != null)
        {
            var e = new PropertyChangedEventArgs(propertyName);
            handler(this, e);
        }
    }

EDIT:
Try changing the resource type from StaticResource to DynamicResource...
http://msdn.microsoft.com/en-us/library/ms750613.aspx#staticdynamic
The resource could be being loaded with the page/window and never updated. That would explain the lack of event communication

Answer 3

You've got this:

WorkModels="{Binding Source={StaticResource ListWorkViewModel}, Path=WorkModels}"

Why are you binding to a static resource? how is that resource defined? Is it in the XAML itself? Are you sure you're actually updating the same instance of the model that the control is bound to?

Answer 4

Thank you for answers. I found the solution to the problem here. http://msdn.microsoft.com/en-us/library/aa970563.aspx

For a dependency property in general, the implementation pattern that you follow is that you define a CLR property wrapper, where that property is backed by a DependencyProperty identifier rather than a field or other construct. You follow this same pattern when you implement a collection-type property. However, a collection-type property introduces some complexity to the pattern whenever the type that is contained within the collection is itself a DependencyObject or Freezable derived class.