Code:
/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Base / System / ComponentModel / PropertyChangedEventManager.cs / 1305600 / PropertyChangedEventManager.cs
//----------------------------------------------------------------------------
//
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//
// Description: Manager for the PropertyChanged event in the "weak event listener"
// pattern. See WeakEventTable.cs for an overview.
//
//---------------------------------------------------------------------------
using System;
using System.Collections; // ICollection
using System.Collections.Specialized; // HybridDictionary
using System.ComponentModel; // INotifyPropertyChanged
using System.Diagnostics; // Debug
using System.Windows; // WeakEventManager
namespace System.ComponentModel
{
///
/// Manager for the INotifyPropertyChanged.PropertyChanged event.
///
public class PropertyChangedEventManager : WeakEventManager
{
#region Constructors
//
// Constructors
//
private PropertyChangedEventManager()
{
}
#endregion Constructors
#region Public Methods
//
// Public Methods
//
///
/// Add a listener to the given source's event.
///
public static void AddListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
if (source == null)
throw new ArgumentNullException("source");
if (listener == null)
throw new ArgumentNullException("listener");
CurrentManager.PrivateAddListener(source, listener, propertyName);
}
///
/// Remove a listener to the given source's event.
///
public static void RemoveListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
/* for app-compat, allow RemoveListener(null, x) - it's a no-op (see Dev10 796788)
if (source == null)
throw new ArgumentNullException("source");
*/
if (listener == null)
throw new ArgumentNullException("listener");
CurrentManager.PrivateRemoveListener(source, listener, propertyName);
}
#endregion Public Methods
#region Protected Methods
//
// Protected Methods
//
///
/// Listen to the given source for the event.
///
protected override void StartListening(object source)
{
INotifyPropertyChanged typedSource = (INotifyPropertyChanged)source;
typedSource.PropertyChanged += new PropertyChangedEventHandler(OnPropertyChanged);
}
///
/// Stop listening to the given source for the event.
///
protected override void StopListening(object source)
{
INotifyPropertyChanged typedSource = (INotifyPropertyChanged)source;
typedSource.PropertyChanged -= new PropertyChangedEventHandler(OnPropertyChanged);
}
///
/// Remove dead entries from the data for the given source. Returns true if
/// some entries were actually removed.
///
protected override bool Purge(object source, object data, bool purgeAll)
{
bool foundDirt = false;
if (!purgeAll)
{
HybridDictionary dict = (HybridDictionary)data;
// copy the keys into a separate array, so that later on
// we can change the dictionary while iterating over the keys
ICollection ic = dict.Keys;
String[] keys = new String[ic.Count];
ic.CopyTo(keys, 0);
for (int i=keys.Length-1; i>=0; --i)
{
if (keys[i] == AllListenersKey)
continue; // ignore the special entry for now
// for each key, remove dead entries in its list
bool removeList = purgeAll || source == null;
if (!removeList)
{
ListenerList list = (ListenerList)dict[keys[i]];
if (ListenerList.PrepareForWriting(ref list))
dict[keys[i]] = list;
if (list.Purge())
foundDirt = true;
removeList = (list.IsEmpty);
}
// if there are no more entries, remove the key
if (removeList)
{
dict.Remove(keys[i]);
}
}
if (dict.Count == 0)
{
// if there are no more listeners at all, remove the entry from
// the main table, and prepare to stop listening
purgeAll = true;
if (source != null) // source may have been GC'd
{
this.Remove(source);
}
}
else if (foundDirt)
{
// if any entries were purged, invalidate the special entry
dict.Remove(AllListenersKey);
_proposedAllListenersList = null;
}
}
if (purgeAll)
{
// stop listening. List cleanup is handled by Purge()
if (source != null) // source may have been GC'd
{
StopListening(source);
}
foundDirt = true;
}
return foundDirt;
}
#endregion Protected Methods
#region Private Properties
//
// Private Properties
//
// get the event manager for the current thread
private static PropertyChangedEventManager CurrentManager
{
get
{
Type managerType = typeof(PropertyChangedEventManager);
PropertyChangedEventManager manager = (PropertyChangedEventManager)GetCurrentManager(managerType);
// at first use, create and register a new manager
if (manager == null)
{
manager = new PropertyChangedEventManager();
SetCurrentManager(managerType, manager);
}
return manager;
}
}
#endregion Private Properties
#region Private Methods
//
// Private Methods
//
// PropertyChanged is a special case - we superimpose per-property granularity
// on top of this event, by keeping separate lists of listeners for
// each property.
// Add a listener to the named property (empty means "any property")
private void PrivateAddListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
Debug.Assert(listener != null && source != null && propertyName != null,
"Listener, source, and propertyName of event cannot be null");
using (WriteLock)
{
HybridDictionary dict = (HybridDictionary)this[source];
if (dict == null)
{
// no entry in the hashtable - add a new one
dict = new HybridDictionary(true /* case insensitive */);
this[source] = dict;
// listen for the desired events
StartListening(source);
}
ListenerList list = (ListenerList)dict[propertyName];
if (list == null)
{
// no entry in the dictionary - add a new one
list = new ListenerList();
dict[propertyName] = list;
}
// make sure list is ready for writing
if (ListenerList.PrepareForWriting(ref list))
{
dict[propertyName] = list;
}
// add a listener to the list
list.Add(listener);
dict.Remove(AllListenersKey); // invalidate list of all listeners
_proposedAllListenersList = null;
// schedule a cleanup pass
ScheduleCleanup();
}
}
// Remove a listener to the named property (empty means "any property")
private void PrivateRemoveListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
Debug.Assert(listener != null && source != null && propertyName != null,
"Listener, source, and propertyName of event cannot be null");
using (WriteLock)
{
HybridDictionary dict = (HybridDictionary)this[source];
if (dict != null)
{
ListenerList list = (ListenerList)dict[propertyName];
if (list != null)
{
// make sure list is ready for writing
if (ListenerList.PrepareForWriting(ref list))
{
dict[propertyName] = list;
}
// remove a listener from the list
list.Remove(listener);
// when the last listener goes away, remove the list
if (list.IsEmpty)
{
dict.Remove(propertyName);
}
}
if (dict.Count == 0)
{
StopListening(source);
Remove(source);
}
dict.Remove(AllListenersKey); // invalidate list of all listeners
_proposedAllListenersList = null;
}
}
}
// event handler for PropertyChanged event
private void OnPropertyChanged(object sender, PropertyChangedEventArgs args)
{
ListenerList list;
string propertyName = args.PropertyName;
// get the list of listeners
using (ReadLock)
{
// look up the list of listeners
HybridDictionary dict = (HybridDictionary)this[sender];
if (dict == null)
{
// this can happen when the last listener stops listening, but the
// source raises the event on another thread after the dictionary
// has been removed (bug 1235351)
list = ListenerList.Empty;
}
else if (!String.IsNullOrEmpty(propertyName))
{
// source has changed a particular property. Notify targets
// who are listening either for this property or for all properties.
ListenerList listeners = (ListenerList)dict[propertyName];
ListenerList genericListeners = (ListenerList)dict[String.Empty];
if (genericListeners == null)
{
if (listeners != null)
{
list = listeners; // only specific listeners
}
else
{
list = ListenerList.Empty; // no listeners at all
}
}
else
{
if (listeners != null)
{
// there are both specific and generic listeners -
// combine the two lists.
list = new ListenerList(listeners.Count + genericListeners.Count);
for (int i=0, n=listeners.Count; i
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//
// Description: Manager for the PropertyChanged event in the "weak event listener"
// pattern. See WeakEventTable.cs for an overview.
//
//---------------------------------------------------------------------------
using System;
using System.Collections; // ICollection
using System.Collections.Specialized; // HybridDictionary
using System.ComponentModel; // INotifyPropertyChanged
using System.Diagnostics; // Debug
using System.Windows; // WeakEventManager
namespace System.ComponentModel
{
///
/// Manager for the INotifyPropertyChanged.PropertyChanged event.
///
public class PropertyChangedEventManager : WeakEventManager
{
#region Constructors
//
// Constructors
//
private PropertyChangedEventManager()
{
}
#endregion Constructors
#region Public Methods
//
// Public Methods
//
///
/// Add a listener to the given source's event.
///
public static void AddListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
if (source == null)
throw new ArgumentNullException("source");
if (listener == null)
throw new ArgumentNullException("listener");
CurrentManager.PrivateAddListener(source, listener, propertyName);
}
///
/// Remove a listener to the given source's event.
///
public static void RemoveListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
/* for app-compat, allow RemoveListener(null, x) - it's a no-op (see Dev10 796788)
if (source == null)
throw new ArgumentNullException("source");
*/
if (listener == null)
throw new ArgumentNullException("listener");
CurrentManager.PrivateRemoveListener(source, listener, propertyName);
}
#endregion Public Methods
#region Protected Methods
//
// Protected Methods
//
///
/// Listen to the given source for the event.
///
protected override void StartListening(object source)
{
INotifyPropertyChanged typedSource = (INotifyPropertyChanged)source;
typedSource.PropertyChanged += new PropertyChangedEventHandler(OnPropertyChanged);
}
///
/// Stop listening to the given source for the event.
///
protected override void StopListening(object source)
{
INotifyPropertyChanged typedSource = (INotifyPropertyChanged)source;
typedSource.PropertyChanged -= new PropertyChangedEventHandler(OnPropertyChanged);
}
///
/// Remove dead entries from the data for the given source. Returns true if
/// some entries were actually removed.
///
protected override bool Purge(object source, object data, bool purgeAll)
{
bool foundDirt = false;
if (!purgeAll)
{
HybridDictionary dict = (HybridDictionary)data;
// copy the keys into a separate array, so that later on
// we can change the dictionary while iterating over the keys
ICollection ic = dict.Keys;
String[] keys = new String[ic.Count];
ic.CopyTo(keys, 0);
for (int i=keys.Length-1; i>=0; --i)
{
if (keys[i] == AllListenersKey)
continue; // ignore the special entry for now
// for each key, remove dead entries in its list
bool removeList = purgeAll || source == null;
if (!removeList)
{
ListenerList list = (ListenerList)dict[keys[i]];
if (ListenerList.PrepareForWriting(ref list))
dict[keys[i]] = list;
if (list.Purge())
foundDirt = true;
removeList = (list.IsEmpty);
}
// if there are no more entries, remove the key
if (removeList)
{
dict.Remove(keys[i]);
}
}
if (dict.Count == 0)
{
// if there are no more listeners at all, remove the entry from
// the main table, and prepare to stop listening
purgeAll = true;
if (source != null) // source may have been GC'd
{
this.Remove(source);
}
}
else if (foundDirt)
{
// if any entries were purged, invalidate the special entry
dict.Remove(AllListenersKey);
_proposedAllListenersList = null;
}
}
if (purgeAll)
{
// stop listening. List cleanup is handled by Purge()
if (source != null) // source may have been GC'd
{
StopListening(source);
}
foundDirt = true;
}
return foundDirt;
}
#endregion Protected Methods
#region Private Properties
//
// Private Properties
//
// get the event manager for the current thread
private static PropertyChangedEventManager CurrentManager
{
get
{
Type managerType = typeof(PropertyChangedEventManager);
PropertyChangedEventManager manager = (PropertyChangedEventManager)GetCurrentManager(managerType);
// at first use, create and register a new manager
if (manager == null)
{
manager = new PropertyChangedEventManager();
SetCurrentManager(managerType, manager);
}
return manager;
}
}
#endregion Private Properties
#region Private Methods
//
// Private Methods
//
// PropertyChanged is a special case - we superimpose per-property granularity
// on top of this event, by keeping separate lists of listeners for
// each property.
// Add a listener to the named property (empty means "any property")
private void PrivateAddListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
Debug.Assert(listener != null && source != null && propertyName != null,
"Listener, source, and propertyName of event cannot be null");
using (WriteLock)
{
HybridDictionary dict = (HybridDictionary)this[source];
if (dict == null)
{
// no entry in the hashtable - add a new one
dict = new HybridDictionary(true /* case insensitive */);
this[source] = dict;
// listen for the desired events
StartListening(source);
}
ListenerList list = (ListenerList)dict[propertyName];
if (list == null)
{
// no entry in the dictionary - add a new one
list = new ListenerList();
dict[propertyName] = list;
}
// make sure list is ready for writing
if (ListenerList.PrepareForWriting(ref list))
{
dict[propertyName] = list;
}
// add a listener to the list
list.Add(listener);
dict.Remove(AllListenersKey); // invalidate list of all listeners
_proposedAllListenersList = null;
// schedule a cleanup pass
ScheduleCleanup();
}
}
// Remove a listener to the named property (empty means "any property")
private void PrivateRemoveListener(INotifyPropertyChanged source, IWeakEventListener listener, string propertyName)
{
Debug.Assert(listener != null && source != null && propertyName != null,
"Listener, source, and propertyName of event cannot be null");
using (WriteLock)
{
HybridDictionary dict = (HybridDictionary)this[source];
if (dict != null)
{
ListenerList list = (ListenerList)dict[propertyName];
if (list != null)
{
// make sure list is ready for writing
if (ListenerList.PrepareForWriting(ref list))
{
dict[propertyName] = list;
}
// remove a listener from the list
list.Remove(listener);
// when the last listener goes away, remove the list
if (list.IsEmpty)
{
dict.Remove(propertyName);
}
}
if (dict.Count == 0)
{
StopListening(source);
Remove(source);
}
dict.Remove(AllListenersKey); // invalidate list of all listeners
_proposedAllListenersList = null;
}
}
}
// event handler for PropertyChanged event
private void OnPropertyChanged(object sender, PropertyChangedEventArgs args)
{
ListenerList list;
string propertyName = args.PropertyName;
// get the list of listeners
using (ReadLock)
{
// look up the list of listeners
HybridDictionary dict = (HybridDictionary)this[sender];
if (dict == null)
{
// this can happen when the last listener stops listening, but the
// source raises the event on another thread after the dictionary
// has been removed (bug 1235351)
list = ListenerList.Empty;
}
else if (!String.IsNullOrEmpty(propertyName))
{
// source has changed a particular property. Notify targets
// who are listening either for this property or for all properties.
ListenerList listeners = (ListenerList)dict[propertyName];
ListenerList genericListeners = (ListenerList)dict[String.Empty];
if (genericListeners == null)
{
if (listeners != null)
{
list = listeners; // only specific listeners
}
else
{
list = ListenerList.Empty; // no listeners at all
}
}
else
{
if (listeners != null)
{
// there are both specific and generic listeners -
// combine the two lists.
list = new ListenerList(listeners.Count + genericListeners.Count);
for (int i=0, n=listeners.Count; i
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- CodeStatementCollection.cs
- RowParagraph.cs
- ToolStripContentPanel.cs
- GC.cs
- ConnectionOrientedTransportManager.cs
- DataControlButton.cs
- TimeSpanConverter.cs
- ErrorFormatterPage.cs
- XmlWriter.cs
- XmlSignificantWhitespace.cs
- QilVisitor.cs
- WebBrowserContainer.cs
- ByteStack.cs
- MemoryRecordBuffer.cs
- Pen.cs
- EntityTemplateFactory.cs
- DelayedRegex.cs
- AnnotationDocumentPaginator.cs
- SystemDiagnosticsSection.cs
- ActivationArguments.cs
- TearOffProxy.cs
- OleDbWrapper.cs
- XsdBuilder.cs
- sqlser.cs
- WindowCollection.cs
- MediaTimeline.cs
- Mapping.cs
- BigInt.cs
- TreeViewItemAutomationPeer.cs
- DefaultTraceListener.cs
- WindowsListBox.cs
- ExpressionBuilderCollection.cs
- PageAsyncTaskManager.cs
- ScriptServiceAttribute.cs
- Scene3D.cs
- MutexSecurity.cs
- ImageAutomationPeer.cs
- Grant.cs
- Pair.cs
- SmtpFailedRecipientsException.cs
- XmlUnspecifiedAttribute.cs
- PageCatalogPart.cs
- Ppl.cs
- ComponentResourceKey.cs
- WebRequest.cs
- TimeZone.cs
- CustomGrammar.cs
- DiscoveryMessageSequence11.cs
- LayeredChannelFactory.cs
- DataGridViewComboBoxEditingControl.cs
- TypeLibConverter.cs
- XmlHierarchicalDataSourceView.cs
- FtpWebRequest.cs
- KeyValueConfigurationElement.cs
- DataGridViewRowHeightInfoNeededEventArgs.cs
- SolidColorBrush.cs
- PcmConverter.cs
- InfoCardRSAOAEPKeyExchangeFormatter.cs
- XmlDataProvider.cs
- EntityDataSourceWrapper.cs
- SequentialWorkflowHeaderFooter.cs
- WriteFileContext.cs
- MasterPage.cs
- MemoryStream.cs
- RegexReplacement.cs
- InvalidPropValue.cs
- CategoryAttribute.cs
- OdbcUtils.cs
- ByteStream.cs
- DataSetUtil.cs
- DurationConverter.cs
- EventSourceCreationData.cs
- ImageSource.cs
- Renderer.cs
- SettingsContext.cs
- SerializationAttributes.cs
- TextTreeTextNode.cs
- PageVisual.cs
- PointCollectionConverter.cs
- MiniModule.cs
- MenuItemBindingCollection.cs
- CodeTypeDelegate.cs
- CannotUnloadAppDomainException.cs
- storepermission.cs
- Utilities.cs
- EntityDataSourceEntitySetNameItem.cs
- TypefaceCollection.cs
- Int32RectValueSerializer.cs
- LayoutInformation.cs
- ColorPalette.cs
- MDIControlStrip.cs
- Clause.cs
- ListSortDescription.cs
- ScrollableControlDesigner.cs
- FixedSOMContainer.cs
- RegexCharClass.cs
- ObjectTypeMapping.cs
- TextEncodedRawTextWriter.cs
- LinqDataSourceInsertEventArgs.cs
- SqlDataReader.cs