protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
using (BlockReentrancy())
{
NotifyCollectionChangedEventHandler eventHandler = CollectionChanged;
if (eventHandler == null)
{
return;
}
Delegate[] delegates = eventHandler.GetInvocationList();
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
DispatcherObject dispatcherObject = handler.Target as DispatcherObject;
if (dispatcherObject != null && dispatcherObject.CheckAccess() == false)
{
dispatcherObject.Dispatcher.Invoke(DispatcherPriority.DataBind, handler, this, e);
}
else
{
handler(this, e);
}
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventHandler Handler, NotifyCollectionChangedEventArgs e)
{
if (e is null)
{
throw new ArgumentNullException(nameof(e));
}
if (Handler is null)
{
return;
}
var invocation_list = Handler.GetInvocationList();
var args = new object[] { this, e };
foreach (var d in invocation_list)
{
var o = d.Target;
switch (o)
{
case ISynchronizeInvoke {
InvokeRequired: true
} synchronize_invoke:
synchronize_invoke.Invoke(d, args);
break;
case DispatcherObject dispatcher_obj when !dispatcher_obj.CheckAccess() && dispatcher_obj.Dispatcher != null:
dispatcher_obj.Dispatcher.Invoke(d, args);
break;
default:
d.DynamicInvoke(args);
break;
}
}
}
/// <summary>
/// 重写集合发生变化事件处理函数。
/// </summary>
/// <param name="e">集合变化事件参数。</param>
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
// 不允许可重入的更改此集合的尝试。
using (BlockReentrancy())
{
if (_collectionChanged != null)
{
var delegates = _collectionChanged.GetInvocationList();
// 遍历调用列表。
foreach (var @delegate in delegates)
{
var handler = (NotifyCollectionChangedEventHandler)@delegate;
// 如果订阅者是DispatcherObject和不同的线程。
if (handler != null)
{
// 目标调度程序线程中的调用处理程序。
handler.Invoke(handler, e);
}
else // 按原样执行处理程序。
{
_collectionChanged(this, e);
}
}
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
if (!this.suspendCollectionChangeNotification)
{
NotifyCollectionChangedEventHandler eventHandler = CollectionChanged;
if (eventHandler != null)
{
Delegate[] delegates = eventHandler.GetInvocationList();
bool isEventInvoked = false;
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
isEventInvoked = false;
if (handler.Target is DispatcherObject)
{
DispatcherObject dispatcherObject = handler.Target as DispatcherObject;
if (dispatcherObject != null && dispatcherObject.CheckAccess() == false)
{
dispatcherObject.Dispatcher.BeginInvoke(DispatcherPriority.DataBind, handler, this, e);
isEventInvoked = true;
}
}
if (!isEventInvoked)
{
handler(this, e);
}
}
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
NotifyCollectionChangedEventHandler collectionChanged = CollectionChanged;
if (collectionChanged == null)
{
return;
}
foreach (Delegate @delegate in collectionChanged.GetInvocationList())
{
var nh = (NotifyCollectionChangedEventHandler)@delegate;
var dispatcherObject = nh.Target as DispatcherObject;
Dispatcher dispatcher = dispatcherObject?.Dispatcher;
if (dispatcher != null && !dispatcher.CheckAccess())
{
dispatcher.BeginInvoke(DispatcherPriority.DataBind,
(Action)(() => nh.Invoke(this,
new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset))));
continue;
}
nh.Invoke(this, e);
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
// Be nice - use BlockReentrancy like MSDN said
using (BlockReentrancy())
{
if (_collectionChanged != null)
{
Delegate[] delegates = _collectionChanged.GetInvocationList();
// Walk thru invocation list
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
var dispatcherObject = handler.Target as System.Windows.Forms.Control;
// If the subscriber is a DispatcherObject and different thread
if (dispatcherObject != null && dispatcherObject.InvokeRequired)
{
// Invoke handler in the target dispatcher's thread
dispatcherObject.Invoke(handler, this, e);
}
else // Execute handler as is
{
_collectionChanged(this, e);
}
}
}
}
}
/// <summary>
/// Taken from http://geekswithblogs.net/NewThingsILearned/archive/2008/01/16/have-worker-thread-update-observablecollection-that-is-bound-to-a.aspx
/// </summary>
/// <param name="e"></param>
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
if (!_suspendCollectionChangeNotification)
{
// Be nice - use BlockReentrancy like MSDN said
using (BlockReentrancy())
{
NotifyCollectionChangedEventHandler eventHandler = CollectionChanged;
if (eventHandler == null)
{
return;
}
Delegate[] delegates = eventHandler.GetInvocationList();
// Walk thru invocation list
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
var dispatcherObject = handler.Target as DispatcherObject;
// If the subscriber is a DispatcherObject and different thread
if (dispatcherObject != null && dispatcherObject.CheckAccess() == false)
{
// Invoke handler in the target dispatcher's thread
dispatcherObject.Dispatcher.BeginInvoke(DispatcherPriority.DataBind, handler, this, e);
}
else // Execute handler as is
{
handler(this, e);
}
}
}
}
}
public static void InvokeCollectionChanged(NotifyCollectionChangedEventHandler collectionChanged, object sender, NotifyCollectionChangedEventArgs e)
{
foreach (NotifyCollectionChangedEventHandler nh in collectionChanged.GetInvocationList())
{
var dispObj = nh.Target as DispatcherObject;
if (dispObj != null)
{
Dispatcher dispatcher = dispObj.Dispatcher;
if (dispatcher != null && !dispatcher.CheckAccess())
{
NotifyCollectionChangedEventHandler nh1 = nh;
dispatcher.BeginInvoke((Action)(() => nh1.Invoke(sender, new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset))),
DispatcherPriority.DataBind);
continue;
}
}
if ((e.NewItems != null && e.NewItems.Count > 1) || (e.OldItems != null && e.OldItems.Count > 1))
{
nh.Invoke(sender, new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
else
{
nh.Invoke(sender, e);
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs args)
{
NotifyCollectionChangedEventHandler eventHandler = CollectionChanged;
if (eventHandler != null)
{
Delegate[] delegates = eventHandler.GetInvocationList();
// Walk thru invocation list
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
var dispatcherObject = handler.Target as DispatcherObject;
// If the subscriber is a DispatcherObject and different thread
if (dispatcherObject != null && dispatcherObject.CheckAccess() == false)
{
// Invoke handler in the target dispatcher's thread
dispatcherObject.Dispatcher.Invoke(DispatcherPriority.DataBind,
handler, this, args);
}
else // Execute handler as is
{
handler(this, args);
}
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
NotifyCollectionChangedEventHandler CollectionChanged = this.CollectionChanged;
if (CollectionChanged != null)
{
foreach (NotifyCollectionChangedEventHandler nh in CollectionChanged.GetInvocationList())
{
DispatcherObject dispObj = nh.Target as DispatcherObject;
if (dispObj != null)
{
Dispatcher dispatcher = dispObj.Dispatcher;
if (dispatcher != null && !dispatcher.CheckAccess())
{
dispatcher.BeginInvoke(
(Action)(() => nh.Invoke(this,
new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset))),
DispatcherPriority.DataBind);
continue;
}
}
nh.Invoke(this, e);
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
// Be nice - use BlockReentrancy like MSDN said
using (BlockReentrancy())
{
if (collectionChanged != null)
{
Delegate[] delegates = collectionChanged.GetInvocationList();
// Walk thru invocation list
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
// If the subscriber is a DispatcherObject and different thread
if (handler != null)
{
// Invoke handler in the target dispatcher's thread
handler.Invoke(handler, e);
}
else // Execute handler as is
{
collectionChanged(this, e);
}
}
}
}
}
public static void ThreadSafeInvoke(
[CanBeNull] this NotifyCollectionChangedEventHandler Handler,
[CanBeNull] object Sender,
[NotNull] NotifyCollectionChangedEventArgs E)
{
if (E is null)
{
throw new ArgumentNullException(nameof(E));
}
if (Handler is null)
{
return;
}
var invocation_list = Handler.GetInvocationList();
var args = new[] { Sender, E };
foreach (var d in invocation_list)
{
var o = d.Target;
switch (o)
{
case ISynchronizeInvoke synchronize_invoke when synchronize_invoke.InvokeRequired:
synchronize_invoke.Invoke(d, args);
break;
case DispatcherObject dispatcher_obj when !dispatcher_obj.CheckAccess() && dispatcher_obj.Dispatcher != null:
dispatcher_obj.Dispatcher.Invoke(d, args);
break;
default:
d.DynamicInvoke(args);
break;
}
}
}
protected void CheckReentrancy ()
{
NotifyCollectionChangedEventHandler eh = CollectionChanged;
// Only have a problem if we have more than one event listener.
if (reentrant.Busy && eh != null && eh.GetInvocationList ().Length > 1)
throw new InvalidOperationException ("Cannot modify the collection while reentrancy is blocked.");
}
/// <summary>
/// Invokes the specified <paramref name="handler"/> in a thread-safe manner. Where normally one
/// has to write the following code:
/// <para />
/// <code>
/// <![CDATA[
/// var handler = CollectionChanged;
/// if (handler != null)
/// {
/// handler(this, e, new NotifyCollectionChangedEventArgs(...));
/// }
/// ]]>
/// </code>
/// <para />
/// One can now write:
/// <para />
/// <code>
/// CollectionChanged.SafeInvoke(this, e, new NotifyCollectionChangedEventArgs(...));
/// </code>
/// </summary>
/// <param name="handler">The handler.</param>
/// <param name="sender">The sender.</param>
/// <param name="e">The event args.</param>
/// <returns><c>true</c> if the event handler was not <c>null</c>; otherwise <c>false</c>.</returns>
public static bool SafeInvoke(this NotifyCollectionChangedEventHandler handler, object sender, NotifyCollectionChangedEventArgs e)
{
if (handler != null)
{
SplitInvoke <NotifyCollectionChangedEventHandler>(handler.GetInvocationList(), x => x(sender, e), sender, e);
return(true);
}
return(false);
}
//CollectionViews raise an error when they are passed a NotifyCollectionChangedEventArgs that indicates more than
//one element has been added or removed. They prefer to receive a "Action=Reset" notification, but this is not suitable
//for applications in code, so we actually check the type we're notifying on and pass a customized event args.
protected virtual void OnCollectionChangedMultiItem(NotifyCollectionChangedEventArgs e)
{
NotifyCollectionChangedEventHandler handlers = this.CollectionChanged;
if (handlers != null)
{
foreach (NotifyCollectionChangedEventHandler handler in handlers.GetInvocationList())
{
handler(this, !(handler.Target is ICollectionView) ? e : new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
}
}
public static IEnumerable <T> GetHandlers <T>(NotifyCollectionChangedEventHandler handler)
{
if (handler == null)
{
yield break;
}
foreach (var invocator in handler.GetInvocationList())
{
if (invocator.Target is T container)
{
yield return(container);
}
}
}
/// <summary>
/// This collection changed event performs thread safe event raising.
/// </summary>
/// <param name="e">The event argument.</param>
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
// Recommended is to avoid reentry
// in collection changed event while collection
// is getting changed on other thread.
using (BlockReentrancy())
{
if (!suspendCollectionChangeNotification)
{
NotifyCollectionChangedEventHandler eventHandler = CollectionChanged;
if (eventHandler == null)
{
return;
}
// Walk thru invocation list.
Delegate[] delegates = eventHandler.GetInvocationList();
foreach
(NotifyCollectionChangedEventHandler handler in delegates)
{
// If the subscriber is a DispatcherObject and different thread.
DispatcherObject dispatcherObject
= handler.Target as DispatcherObject;
if (dispatcherObject != null)
{
if (!dispatcherObject.CheckAccess())
{
// Invoke handler in the target dispatcher's thread...
// asynchronously for better responsiveness.
dispatcherObject.Dispatcher.BeginInvoke
(DispatcherPriority.DataBind, handler, this, e);
}
else
{
// Execute handler as is.
handler(this, e);
}
}
else
{
// Execute handler as is.
handler(this, e);
}
}
}
}
}
protected virtual void OnCollectionChanged(NotifyCollectionChangedEventArgs args)
{
NotifyCollectionChangedEventHandler notifyCollectionChangedEventHandler = CollectionChanged;
if (notifyCollectionChangedEventHandler == null)
{
return;
}
foreach (NotifyCollectionChangedEventHandler handler in notifyCollectionChangedEventHandler.GetInvocationList())
{
if (handler.Target is DispatcherObject dispatcherObject && !dispatcherObject.CheckAccess())
{
dispatcherObject.Dispatcher.Invoke(DispatcherPriority.DataBind, handler, this, args);
}
public bool RemoveCollectionChangedSubscribersAll()
{
NotifyCollectionChangedEventHandler _event = CollectionChanged;
if (_event == null) // No subscriber
{
return(false);
}
// Go through handler
foreach (NotifyCollectionChangedEventHandler handler in _event.GetInvocationList())
{
CollectionChanged -= handler;
}
return(true);
}
public static void Start(
[CanBeNull] this NotifyCollectionChangedEventHandler Handler,
object Sender,
NotifyCollectionChangedEventArgs e)
{
if (Handler == null)
{
return;
}
foreach (Delegate invocation in Handler.GetInvocationList())
{
if (invocation.Target is ISynchronizeInvoke target && target.InvokeRequired)
{
target.Invoke(invocation, new object[2]
{
Sender,
(object)e
});
}
protected virtual void OnCollectionChangedMultiItem(NotifyCollectionChangedEventArgs e)
{
NotifyCollectionChangedEventHandler handlers = CollectionChanged;
if (handlers != null)
{
foreach (NotifyCollectionChangedEventHandler handler in handlers.GetInvocationList())
{
if (handler.Target is CollectionView)
{
((CollectionView)handler.Target).Refresh();
}
else
{
handler(this, e);
}
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
// Be nice - use BlockReentrancy like MSDN said
using (BlockReentrancy())
{
NotifyCollectionChangedEventHandler eventHandler = CollectionChanged;
if (eventHandler == null)
{
return;
}
Delegate[] delegates = eventHandler.GetInvocationList();
// Walk thru invocation list
foreach (NotifyCollectionChangedEventHandler handler in delegates.Cast <NotifyCollectionChangedEventHandler>())
{
NotifyCollectionChangedEventHandler handler1 = handler;
_dispatcherInvoker.Invoke(() => handler1(this, e));
}
}
}
public static void InvokeCollectionChanged(NotifyCollectionChangedEventHandler collectionChanged, object sender, NotifyCollectionChangedEventArgs e)
{
foreach (NotifyCollectionChangedEventHandler nh in collectionChanged.GetInvocationList())
{
var dispObj = nh.Target as DispatcherObject;
if (dispObj != null)
{
Dispatcher dispatcher = dispObj.Dispatcher;
if (dispatcher != null && !dispatcher.CheckAccess())
{
NotifyCollectionChangedEventHandler nh1 = nh;
dispatcher.BeginInvoke((Action) (() => nh1.Invoke(sender, new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset))),
DispatcherPriority.DataBind);
continue;
}
}
nh.Invoke(sender, IsRangeAction(e) ? new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset) : e);
}
}
private void OnCollectionChanged(NotifyCollectionChangedEventHandler eventHandler, NotifyCollectionChangedEventArgs e)
{
// Walk through invocation list.
Delegate[] delegates = eventHandler.GetInvocationList();
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
// If the subscriber is a DispatcherObject and different thread.
var dispatcherObject = handler.Target as DispatcherObject;
if (dispatcherObject != null && !dispatcherObject.CheckAccess())
{
// Invoke handler in the target dispatcher's thread...
// asynchronously for better responsiveness.
dispatcherObject.Dispatcher.BeginInvoke(DispatcherPriority.DataBind, handler, this, e);
}
else
{
// Execute handler as is.
handler(this, e);
}
}
}
/// <summary>
/// Invokes the change event on the dispatcher if needed.
/// </summary>
/// <param name="handler">The NotifyCollectionChangedEventHandler.</param>
/// <param name="sender">The sender.</param>
/// <param name="e">The <see cref="NotifyCollectionChangedEventArgs"/>.</param>
public static Task InvokeOnDispatcherAsync(this NotifyCollectionChangedEventHandler handler, object sender, NotifyCollectionChangedEventArgs e)
{
if (handler == null)
{
return(FinishedTask);
}
var invocationList = handler.GetInvocationList();
if (invocationList.Length == 0)
{
return(FinishedTask);
}
if (invocationList.Length == 1)
{
return(NotifyAsync(sender, e, invocationList[0]));
}
return(Task.WhenAll(invocationList.Select(x => NotifyAsync(sender, e, x))));
}
public bool RemoveCollectionChangedSubscriber(object subscriber)
{
NotifyCollectionChangedEventHandler _event = CollectionChanged;
if (_event == null) // No subscriber
{
return(false);
}
// Go through handler
foreach (NotifyCollectionChangedEventHandler handler in _event.GetInvocationList())
{
if (object.ReferenceEquals(handler.Target, subscriber))
{
CollectionChanged -= handler;
return(true);
}
}
return(false);
}
public static void InvokeOnDispatcher(this NotifyCollectionChangedEventHandler handler, object sender, NotifyCollectionChangedEventArgs e)
{
if (handler == null)
{
return;
}
var invocationList = handler.GetInvocationList().OfType <NotifyCollectionChangedEventHandler>();
foreach (var invocation in invocationList)
{
var dispatcherObject = invocation.Target as DispatcherObject;
if (dispatcherObject != null && !dispatcherObject.CheckAccess())
{
dispatcherObject.Dispatcher.Invoke(DispatcherPriority.DataBind, invocation, sender, e);
}
else
{
invocation(sender, e); // note : this does not execute invocation in target thread's context
}
}
}
public void Invoke(NotifyCollectionChangedEventHandler eventHandler, object source, NotifyCollectionChangedEventArgs args)
{
if (eventHandler == null)
{
return;
}
var delegates = eventHandler.GetInvocationList();
async void BeginInvoke(Delegate d)
{
//Debug.Print(args.ToString());
switch (d.Target)
{
case DispatcherObject dispatcherObject:
await dispatcherObject.Dispatcher.BeginInvoke(DispatcherPriority.DataBind, d, source, args);
break;
case ISynchronizeInvoke s:
s.BeginInvoke(d, new[] { source, args });
break;
default:
d.Method.Invoke(d.Target, new object[] { source, args });
//Application.Current?.Dispatcher.BeginInvoke(DispatcherPriority.DataBind, d, source, args);
//var t = new Task(() => d.Method.Invoke(d.Target, new object[] {source, args}));
//t.Start();
//await t;
//d.DynamicInvoke(source, args); // note : this does not execute handler in target thread's context
break;
}
}
foreach (var d in delegates)
{
BeginInvoke(d);
}
}
/// <summary>
/// 必要ならGUIスレッド上でCollectionChangedを呼び出します。
/// </summary>
public static void CallCollectionChanged(NotifyCollectionChangedEventHandler handler,
object sender,
NotifyCollectionChangedEventArgs e)
{
if (handler == null)
{
return;
}
// 個々のDelegate単位で呼び出すスレッドを変更します。
foreach (NotifyCollectionChangedEventHandler child in
handler.GetInvocationList())
{
var target = child.Target as DispatcherObject;
try
{
// 必要があれば指定のスレッド上で実行します。
if (target != null && !target.Dispatcher.CheckAccess())
{
// コレクションの状態が変わる前に変更通知を出す
// 必要があるため、Invokeを使っています。
target.Dispatcher.Invoke(
child,
sender, e);
}
else
{
child(sender, e);
}
}
catch (Exception ex)
{
Log.ErrorException(ex,
"CollectionChangedの呼び出しに失敗しました。");
}
}
}
protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
if (e.NewItems != null)
{
foreach (var item in e.NewItems)
{
(item as INotifyPropertyChanged).PropertyChanged += MyObservableCollection_PropertyChanged;
}
}
if (e.OldItems != null)
{
foreach (var item in e.OldItems)
{
(item as INotifyPropertyChanged).PropertyChanged -= MyObservableCollection_PropertyChanged;
}
}
using (BlockReentrancy())
{
if (!this.suspendCollectionChangeNotification)
{
NotifyCollectionChangedEventHandler eventHandler =
this.CollectionChanged;
if (eventHandler == null)
{
return;
}
// Walk thru invocation list.
Delegate[] delegates = eventHandler.GetInvocationList();
foreach
(NotifyCollectionChangedEventHandler handler in delegates)
{
handler(this, e);
}
}
}
}
/// <summary>
/// Provides a thread-safe means of notfying all subscribers.
/// </summary>
/// <param name="e">The event args to send.</param>
protected virtual void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
{
lock (_onCollectionChangedLock)
{
NotifyCollectionChangedEventHandler eventHandler = CollectionChanged;
if (eventHandler != null)
{
Delegate[] delegates = eventHandler.GetInvocationList();
foreach (NotifyCollectionChangedEventHandler handler in delegates)
{
// Check if we need to invoke the handler on a different thread.
if (handler.Target is DispatcherObject dispatcherObject && dispatcherObject.CheckAccess() == false)
{
dispatcherObject.Dispatcher.Invoke(DispatcherPriority.DataBind, handler, this, e);
}
else
{
handler(this, e);
}
}
}
