public override void Recalculate()
{
if (_isDismissed)
{
throw (new InvalidOperationException("Cannot recalculate. The session is dismissed."));
}
// Clear out the active set of signatures.
_activeSignatures.Clear();
// In order to find the signatures to be displayed in this session, we'll need to go through each of the signature help
// providers and ask them for signatures at the trigger point.
List <ISignature> signatures = new List <ISignature>();
foreach (ISignatureHelpSource provider in _componentContext.GetSignatureHelpSources(this))
{
provider.AugmentSignatureHelpSession(this, signatures);
// The source could have done anything to the session. Let's verify that we're still alive and well.
if (this.IsDismissed)
{
return;
}
}
if (signatures != null)
{
_activeSignatures.AddRange(signatures);
}
// If we ended-up with zero signatures, that's it. We need to dismiss and get out of here.
if (_activeSignatures.Count == 0)
{
this.Dismiss();
return;
}
// Let's determine which signature should be "selected" before we find a presenter.
if (!_activeSignatures.Contains(_selectedSignature))
{
// The old selection is no longer valid (or we never had one). Let's select the first signature.
this.SelectedSignature = _activeSignatures[0];
}
// If we don't already have a presenter for this session, find one.
if (base.presenter == null)
{
base.presenter = FindPresenter(this, _componentContext.OrderedIntellisensePresenterProviderExports, _componentContext.GuardedOperations);
if (base.presenter != null)
{
this.RaisePresenterChanged();
}
else
{
this.Dismiss();
return;
}
}
base.RaiseRecalculated();
}