Returning objects from another thread?
- by Mark
Trying to follow the hints laid out here, but she doesn't mention how to handle it when your collection needs to return a value, like so:
private delegate TValue DequeueHandler();
public virtual TValue Dequeue()
{
if (dispatcher.CheckAccess())
{
--count;
var pair = dict.First();
var queue = pair.Value;
var val = queue.Dequeue();
if (queue.Count == 0) dict.Remove(pair.Key);
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, val));
return val;
}
else
{
dispatcher.BeginInvoke(new DequeueHandler(Dequeue));
}
}
This obviously won't work, because dispatcher.BeginInvoke doesn't return anything. What am I supposed to do?
Or maybe I could replace dequeue with two functions, Peek and Pop, where Peek doesn't really need to be on the UI thread because it doesn't modify anything, right?
As a side question, these methods don't need to be "locked" either, do they? If they're all forced to run in the UI thread, then there shouldn't be any concurrency issues, right?