BeginInvoke on ObservableCollection not immediate.
- by Padu Merloti
In my code I subscribe to an event that happens on a different thread. Every time this event happens, I receive an string that is posted to the observable collection:
Dispatcher currentDispatcher = Dispatcher.CurrentDispatcher;
var SerialLog = new ObservableCollection<string>();
private void hitStation_RawCommandSent(object sender, StringEventArgs e)
{
string command = e.Value.Replace("\r\n", "");
Action dispatchAction = () => SerialLog.Add(command);
currentDispatcher.BeginInvoke(dispatchAction, DispatcherPriority.Render);
}
The code below is in my view model (could be in the code behind, it doesn't matter in this case). When I call "hitstation.PrepareHit", the event above gets called a couple times, then I wait and call "hitStation.HitBall", and the event above gets called a couple more times.
private void HitBall()
{
try
{
try
{
Mouse.OverrideCursor = Cursors.Wait;
//prepare hit
hitStation.PrepareHit(hitSpeed);
Thread.Wait(1000);
PlayWarning();
//hit
hitStation.HitBall(hitSpeed);
}
catch (TimeoutException ex)
{
MessageBox.Show("Timeout hitting ball: " + ex.Message);
}
}
finally
{
Mouse.OverrideCursor = null;
}
}
The problem I'm having is that the ListBox that is bound to my SerialLog gets updated only when the HitBall method finishes. I was expecting seeing a bunch of updates from the PrepareHit, a pause and then a bunch more updates from the HitBall.
I've tried a couple of DispatcherPriority arguments, but they don't seem to have any effect.