void ModelPropertyChanged(object sender, PropertyChangedEventArgs e)
{
switch (e.PropertyName)
{
case nameof(viewModel.Sessions):
(ISet <SessionModel> removedModels, _, ISet <SessionModel> addedModels) = e.Diff <SessionModel>();
foreach (SessionModel model in removedModels)
{
sessions.RemoveSession(model);
}
foreach (SessionModel model in addedModels)
{
sessions.AddSession(model);
}
break;
}
}