|
//---------------------------------------------------------------------------
//
// <copyright file="CompositeCollection.cs" company="Microsoft">
// Copyright (C) 2003 by Microsoft Corporation. All rights reserved.
// </copyright>
//
//
// Description: CompositeCollection holds the list of items that constitute the content of a ItemsControl.
//
// See specs at http://avalon/connecteddata/Specs/ItemsControl.mht
//
// History:
// 09/22/2003 : kenlai - moved from ItemCollection
//
//---------------------------------------------------------------------------
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Windows;
using System.Windows.Markup;
using MS.Internal; // Invariant.Assert
using MS.Internal.Data;
using MS.Utility;
using System;
namespace System.Windows.Data
{
/// <summary>
/// CompositeCollection will contain items shaped as strings, objects, xml nodes,
/// elements as well as other collections.
/// A <seealso cref="System.Windows.Controls.ItemsControl"/> uses the data
/// in the CompositeCollection to generate its content according to its ItemTemplate.
/// </summary>
[Localizability(LocalizationCategory.Ignore)]
public class CompositeCollection : IList, INotifyCollectionChanged, ICollectionViewFactory, IWeakEventListener
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
/// <summary>
/// Initializes a new instance of CompositeCollection that is empty and has default initial capacity.
/// </summary>
public CompositeCollection()
{
Initialize(new ArrayList());
}
/// <summary>
/// Initializes a new instance of CompositeCollection that is empty and has specified initial capacity.
/// </summary>
/// <param name="capacity">The number of items that the new list is initially capable of storing</param>
/// <remarks>
/// Some ItemsControl implementations have better idea how many items to anticipate,
/// capacity parameter lets them tailor the initial size.
/// </remarks>
public CompositeCollection(int capacity)
{
Initialize(new ArrayList(capacity));
}
#endregion Constructors
//------------------------------------------------------
//
// Public Methods
//
//------------------------------------------------------
#region Public Methods
/// <summary>
/// Returns an enumerator object for this CompositeCollection
/// </summary>
/// <returns>
/// Enumerator object for this CompositeCollection
/// </returns>
IEnumerator IEnumerable.GetEnumerator()
{
// Enumerator from the underlying ArrayList
return InternalList.GetEnumerator();
}
/// <summary>
/// Makes a shallow copy of object references from this
/// CompositeCollection to the given target array
/// </summary>
/// <param name="array">
/// Target of the copy operation
/// </param>
/// <param name="index">
/// Zero-based index at which the copy begins
/// </param>
public void CopyTo(Array array, int index)
{
// Forward call to internal list.
InternalList.CopyTo(array, index);
}
/// <summary>
/// Add an item to this collection.
/// </summary>
/// <param name="newItem">
/// New item to be added to collection
/// </param>
/// <returns>
/// Zero-based index where the new item is added.
/// </returns>
/// <exception cref="ArgumentException">
/// CompositeCollection can only accept CollectionContainers it doesn't already have.
/// </exception>
public int Add(object newItem)
{
CollectionContainer cc = newItem as CollectionContainer;
if (cc != null)
{
AddCollectionContainer(cc);
}
int addedIndex = InternalList.Add(newItem);
OnCollectionChanged(NotifyCollectionChangedAction.Add, newItem, addedIndex);
return addedIndex;
}
/// <summary>
/// Clears the collection. Releases the references on all items
/// currently in the collection.
/// </summary>
public void Clear()
{
// unhook contained collections
for (int k=0, n=InternalList.Count; k < n; ++k)
{
CollectionContainer cc = this[k] as CollectionContainer;
if (cc != null)
{
RemoveCollectionContainer(cc);
}
}
InternalList.Clear();
OnCollectionChanged(NotifyCollectionChangedAction.Reset);
}
/// <summary>
/// Checks to see if a given item is in this collection
/// </summary>
/// <param name="containItem">
/// The item whose membership in this collection is to be checked.
/// </param>
/// <returns>
/// True if the collection contains the given item
/// </returns>
public bool Contains(object containItem)
{
return InternalList.Contains(containItem);
}
/// <summary>
/// Finds the index in this collection where the given item is found.
/// </summary>
/// <param name="indexItem">
/// The item whose index in this collection is to be retrieved.
/// </param>
/// <returns>
/// Zero-based index into the collection where the given item can be
/// found. Otherwise, -1
/// </returns>
public int IndexOf(object indexItem)
{
return InternalList.IndexOf(indexItem);
}
/// <summary>
/// Insert an item in the collection at a given index. All items
/// after the given position are moved down by one.
/// </summary>
/// <param name="insertIndex">
/// The index at which to inser the item
/// </param>
/// <param name="insertItem">
/// The item reference to be added to the collection
/// </param>
/// <exception cref="ArgumentOutOfRangeException">
/// Thrown if index is out of range
/// </exception>
public void Insert(int insertIndex, object insertItem)
{
CollectionContainer cc = insertItem as CollectionContainer;
if (cc != null)
{
AddCollectionContainer(cc);
}
// ArrayList implementation checks index and will throw out of range exception
InternalList.Insert(insertIndex, insertItem);
OnCollectionChanged(NotifyCollectionChangedAction.Add, insertItem, insertIndex);
}
/// <summary>
/// Removes the given item reference from the collection. All
/// remaining items move up by one.
/// </summary>
/// <param name="removeItem">
/// The item to be removed.
/// </param>
public void Remove(object removeItem)
{
int index = InternalList.IndexOf(removeItem);
if (index >= 0)
{
// to ensure model parent is cleared and the CollectionChange notification is raised,
// call this.RemoveAt, not the aggregated ArrayList
this.RemoveAt(index);
}
}
/// <summary>
/// Removes an item from the collection at the given index. All
/// remaining items move up by one.
/// </summary>
/// <param name="removeIndex">
/// The index at which to remove an item.
/// </param>
/// <exception cref="ArgumentOutOfRangeException">
/// Thrown if index is out of range
/// </exception>
public void RemoveAt(int removeIndex)
{
if ((0 <= removeIndex) && (removeIndex < Count))
{
object removedItem = this[removeIndex];
CollectionContainer cc = removedItem as CollectionContainer;
if (cc != null)
{
RemoveCollectionContainer(cc);
}
InternalList.RemoveAt(removeIndex);
OnCollectionChanged(NotifyCollectionChangedAction.Remove, removedItem, removeIndex);
}
else
{
throw new ArgumentOutOfRangeException("removeIndex",
SR.Get(SRID.ItemCollectionRemoveArgumentOutOfRange));
}
}
/// <summary>
/// Create a new view on this collection [Do not call directly].
/// </summary>
/// <remarks>
/// Normally this method is only called by the platform's view manager,
/// not by user code.
/// </remarks>
ICollectionView ICollectionViewFactory.CreateView()
{
return new CompositeCollectionView(this);
}
#endregion Public Methods
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
#region Public Properties
/// <summary>
/// Read-only property for the number of items stored in this collection of objects
/// </summary>
/// <remarks>
/// CollectionContainers each count as 1 item.
/// When in ItemsSource mode, Count always equals 1.
/// </remarks>
public int Count
{
get
{
// Return value from the underlying ArrayList.
return InternalList.Count;
}
}
/// <summary>
/// Indexer property to retrieve or replace the item at the given
/// zero-based offset into the collection.
/// </summary>
/// <exception cref="ArgumentOutOfRangeException">
/// Thrown if index is out of range
/// </exception>
public object this[int itemIndex]
{
get
{
// ArrayList implementation checks index and will throw out of range exception
return InternalList[itemIndex];
}
set
{
// ArrayList implementation checks index and will throw out of range exception
object originalItem = InternalList[itemIndex];
// unhook the old, hook the new
CollectionContainer cc;
if ((cc = originalItem as CollectionContainer) != null)
{
RemoveCollectionContainer(cc);
}
if ((cc = value as CollectionContainer) != null)
{
AddCollectionContainer(cc);
}
// make the change
InternalList[itemIndex] = value;
OnCollectionChanged(NotifyCollectionChangedAction.Replace, originalItem, value, itemIndex);
}
}
/// <summary>
/// Gets a value indicating whether access to the CompositeCollection is synchronized (thread-safe).
/// </summary>
bool ICollection.IsSynchronized
{
get
{
// Return value from the underlying ArrayList.
return InternalList.IsSynchronized;
}
}
/// <summary>
/// Returns an object to be used in thread synchronization.
/// </summary>
object ICollection.SyncRoot
{
get
{
// Return the SyncRoot object of the underlying ArrayList
return InternalList.SyncRoot;
}
}
/// <summary>
/// Gets a value indicating whether the IList has a fixed size.
/// An CompositeCollection can usually grow dynamically,
/// this call will commonly return FixedSize = False.
/// In ItemsSource mode, this call will return IsFixedSize = True.
/// </summary>
bool IList.IsFixedSize
{
get
{
return InternalList.IsFixedSize;
}
}
/// <summary>
/// Gets a value indicating whether the IList is read-only.
/// An CompositeCollection is usually writable,
/// this call will commonly return IsReadOnly = False.
/// In ItemsSource mode, this call will return IsReadOnly = True.
/// </summary>
bool IList.IsReadOnly
{
get
{
return InternalList.IsReadOnly;
}
}
#endregion Public Properties
//------------------------------------------------------
//
// Public Events
//
//------------------------------------------------------
#region Public Events
/// <summary>
/// Occurs when the collection changes, either by adding or removing an item
/// <see cref="INotifyCollectionChanged" />
/// </summary>
event NotifyCollectionChangedEventHandler INotifyCollectionChanged.CollectionChanged
{
add
{
CollectionChanged += value;
}
remove
{
CollectionChanged -= value;
}
}
/// <summary>
/// Occurs when the collection changes, either by adding or removing an item.
/// </summary>
protected event NotifyCollectionChangedEventHandler CollectionChanged;
#endregion Public Events
#region IWeakEventListener
/// <summary>
/// Handle events from the centralized event table
/// </summary>
bool IWeakEventListener.ReceiveWeakEvent(Type managerType, object sender, EventArgs e)
{
return ReceiveWeakEvent(managerType, sender, e);
}
/// <summary>
/// Handle events from the centralized event table
/// </summary>
protected virtual bool ReceiveWeakEvent(Type managerType, object sender, EventArgs e)
{
return false; // this method is no longer used (but must remain, for compat)
}
#endregion IWeakEventListener
//------------------------------------------------------
//
// Internal Events
//
//------------------------------------------------------
#region Internal Events
internal event NotifyCollectionChangedEventHandler ContainedCollectionChanged;
private void OnContainedCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (ContainedCollectionChanged != null)
ContainedCollectionChanged(sender, e);
}
#endregion Internal Events
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
#region Private Methods
// common ctor initialization
private void Initialize(ArrayList internalList)
{
_internalList = internalList;
}
// ArrayList that holds collection containers as well as single items
private ArrayList InternalList
{
get
{
return _internalList;
}
}
// Hook up to a newly-added CollectionContainer
private void AddCollectionContainer(CollectionContainer cc)
{
if (InternalList.Contains(cc))
throw new ArgumentException(SR.Get(SRID.CollectionContainerMustBeUniqueForComposite), "cc");
CollectionChangedEventManager.AddHandler(cc, OnContainedCollectionChanged);
#if DEBUG
_hasRepeatedCollectionIsValid = false;
#endif
}
// Unhook a newly-deleted CollectionContainer
private void RemoveCollectionContainer(CollectionContainer cc)
{
CollectionChangedEventManager.RemoveHandler(cc, OnContainedCollectionChanged);
#if DEBUG
_hasRepeatedCollectionIsValid = false;
#endif
}
// raise CollectionChanged event to any listeners
void OnCollectionChanged(NotifyCollectionChangedAction action)
{
#if DEBUG
_hasRepeatedCollectionIsValid = false;
#endif
if (CollectionChanged != null)
{
CollectionChanged(this, new NotifyCollectionChangedEventArgs(action));
}
}
// raise CollectionChanged event to any listeners
void OnCollectionChanged(NotifyCollectionChangedAction action, object item, int index)
{
if (CollectionChanged != null)
{
CollectionChanged(this, new NotifyCollectionChangedEventArgs(action, item, index));
}
}
/// raise CollectionChanged event to any listeners
void OnCollectionChanged(NotifyCollectionChangedAction action, object oldItem, object newItem, int index)
{
if (CollectionChanged != null)
{
CollectionChanged(this, new NotifyCollectionChangedEventArgs(action, newItem, oldItem, index));
}
}
#endregion Private Methods
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
private ArrayList _internalList;
#endregion Private Fields
//------------------------------------------------------
//
// Debugging Aids
//
//------------------------------------------------------
#region Debugging Aids
#if DEBUG
internal bool HasRepeatedCollection()
{
if (!_hasRepeatedCollectionIsValid)
{
_hasRepeatedCollection = FindRepeatedCollection(new ArrayList());
_hasRepeatedCollectionIsValid = true;
}
return _hasRepeatedCollection;
}
// recursive depth-first search for repeated collection
private bool FindRepeatedCollection(ArrayList collections)
{
for (int i = 0; i < Count; ++i)
{
CollectionContainer cc = this[i] as CollectionContainer;
if (cc != null && cc.Collection != null)
{
CompositeCollection composite = cc.Collection as CompositeCollection;
if (composite != null)
{
if (composite.FindRepeatedCollection(collections))
return true;
}
else if (collections.IndexOf(cc.Collection) > -1)
return true;
else
collections.Add(cc.Collection);
}
}
return false;
}
private bool _hasRepeatedCollection = false;
private bool _hasRepeatedCollectionIsValid = false;
#endif
internal void GetCollectionChangedSources(int level, Action<int, object, bool?, List<string>> format, List<string> sources)
{
format(level, this, false, sources);
foreach (object o in InternalList)
{
CollectionContainer cc = o as CollectionContainer;
if (cc != null)
{
cc.GetCollectionChangedSources(level+1, format, sources);
}
}
}
#endregion Debugging Aids
}
}
|