ObservableCollection in Model + Threading in ViewModel
Our offsite development team created a Model with an ObservableCollection property. Now, I'm in charge of creating the ViewModel, and I'm having trouble because the said Model runs inside a BackgroundWorker (another thread)- which means I can't update the View by hooking the CollectionChanged events. Here's the workaround that I did:
private Model model = new Model();
public ObservableCollection<Entry> Entries { get; set; }
public ctor()
{
BackgroundWorker peon = new BackgroundWorker();
peon.DoWork += work;
peon.RunWorkerCompleted += updateViewCollection;
peon.RunWorkerAsync();
}
private void work(object sender, DoWorkEventArgs e)
{
model.DoSomething();
}
private void updateViewCollection(object sender, RunWorkerCompletedEventArgs e)
{
// model.entries is an ObservableCollection<Entry>
foreach (Entry en in this.model.entries)
{
if (!this.Entries.Contains(en))
开发者_开发知识库 this.Entries.Add(en);
}
}
Is there a better way to hook the ObservableCollection of the Model to the ObservableCollection of the View through a Threaded ViewModel?
I am assuming you are using either wpf or silverlight. You hook the events the same as you would on a single thread, but marshal them back onto the Dispatcher object (Invoke()). Assuming your observable collection is thread safe you should have no problem.
Take a look at this http://nuget.org/List/Packages/Caliburn.Micro.INPC
It has a view model base that implements property changed that automatically marshals to the ui thread. there is also a class that Extends ObservableCollection that does the same thing called BindableCollection.
精彩评论