protected virtual void Dispose(bool disposing)
{
if (_disposed)
{
return;
}
if (disposing)
{
_listeners.Dispose();
if (typeof(IDisposable).IsAssignableFrom(typeof(T)))
{
foreach (var i in _list.OfType <IDisposable>())
{
i.Dispose();
}
}
}
_disposed = true;
}
public static ReadOnlyDispatcherCollection <TViewModel> CreateReadOnlyDispatcherCollection <TModel, TViewModel>(
[NotNull] IList <TModel> source, [NotNull] Func <TModel, TViewModel> converter,
[NotNull] Dispatcher dispatcher)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
if (converter == null)
{
throw new ArgumentNullException(nameof(converter));
}
if (dispatcher == null)
{
throw new ArgumentNullException(nameof(dispatcher));
}
if (!(source is INotifyCollectionChanged sourceAsNotifyCollection))
{
throw new ArgumentException("sourceがINotifyCollectionChangedを実装していません");
}
var initCollection = new ObservableCollection <TViewModel>();
foreach (var model in source)
{
initCollection.Add(converter(model));
}
var target = new DispatcherCollection <TViewModel>(initCollection, dispatcher);
var result = new ReadOnlyDispatcherCollection <TViewModel>(target);
var collectionChangedListener = new CollectionChangedEventListener(sourceAsNotifyCollection);
result.EventListeners.Add(collectionChangedListener);
collectionChangedListener.RegisterHandler((sender, e) =>
{
if (e == null)
{
throw new ArgumentNullException(nameof(e));
}
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
var vm = converter((TModel)e.NewItems?[0]);
InvokeOnDispatcher(() => target.Insert(e.NewStartingIndex, vm), dispatcher);
break;
case NotifyCollectionChangedAction.Move:
InvokeOnDispatcher(() => target.Move(e.OldStartingIndex, e.NewStartingIndex), dispatcher);
break;
case NotifyCollectionChangedAction.Remove:
if (typeof(IDisposable).IsAssignableFrom(typeof(TViewModel)))
{
((IDisposable)target[e.OldStartingIndex])?.Dispose();
}
InvokeOnDispatcher(() => target.RemoveAt(e.OldStartingIndex), dispatcher);
break;
case NotifyCollectionChangedAction.Replace:
if (typeof(IDisposable).IsAssignableFrom(typeof(TViewModel)))
{
((IDisposable)target[e.NewStartingIndex])?.Dispose();
}
var replaceVm = converter((TModel)e.NewItems?[0]);
InvokeOnDispatcher(() => target[e.NewStartingIndex] = replaceVm, dispatcher);
break;
case NotifyCollectionChangedAction.Reset:
if (typeof(IDisposable).IsAssignableFrom(typeof(TViewModel)))
{
foreach (var item in target.OfType <IDisposable>())
{
item.Dispose();
}
}
InvokeOnDispatcher(target.Clear, dispatcher);
break;
default:
throw new ArgumentException();
}
});
return(result);
}
