Question

I am having an issue where my ObservableCollection is not updating the view. I can place a breakpoint prior to the OnPropertyChange and can verify that my collection has the names in them.

In my model i have a event that fires a List with random names in it.

in my view model i subscribe to this event and my event handler does this

void _manager_ProcessesChanged(List<string> n)
    {
        //create a new collection to hold current Ids
        ObservableCollection<string> names = new ObservableCollection<string>();

        //copy ids into our collection
        foreach (string name in n)
        {
            names.Add(name);
        }

        Names = names;
    }

my Names property looks like so

ObservableCollection<string> _names = new ObservableCollection<string>();
public ObservableCollection<string> Names
    {
        get { return _names; }
        set
        {
            _names = value;
           OnPropertyChanged("Names");
        }
    }

and my view binds looks like this

<Window.DataContext>
    <vm:MainWindowViewModel/>
</Window.DataContext>
<Grid>
    <ListBox ItemsSource="{Binding Path=Names}"/>
</Grid>

If i change the collection for <string> to <int> it seems to work fine.. what am i missing?

Answer 1

I’ve run into this as well. Not sure if this is the ideal solution (sure doesn’t seem like it) but this has worked for me

void _manager_ProcessesChanged(List<string> n)
{
    Names.Clear();

    //copy ids into our collection
    foreach (string name in n)
    {
        Names.Add(name);
    }
}