/// <summary>
/// Suspends the change notifications until the returned <see cref="IDisposable"/> is disposed.
/// <example>
/// <code>
/// <![CDATA[
/// var fastCollection = new FastObservableCollection<int>();
/// using (fastCollection.SuspendChangeNotificaftions())
/// {
/// // Adding or removing events inside here will not raise events
/// fastCollection.Add(1);
/// fastCollection.Add(2);
/// fastCollection.Add(3);
///
/// fastCollection.Remove(3);
/// fastCollection.Remove(2);
/// fastCollection.Remove(1);
/// }
/// ]]>
/// </code>
/// </example>
/// </summary>
/// <param name="mode">The suspension Mode.</param>
/// <returns>IDisposable.</returns>
public IDisposable SuspendChangeNotifications(SuspensionMode mode)
{
if (_suspensionContext == null)
{
// Create new context
_suspensionContext = new SuspensionContext <T>(mode);
}
else if (_suspensionContext != null && _suspensionContext.Mode != mode)
{
throw Log.ErrorAndCreateException <InvalidOperationException>("Cannot change mode during another active suspension.");
}
return(new DisposableToken <FastObservableCollection <T> >(
this,
x =>
{
x.Instance._suspensionContext.Count++;
},
x =>
{
x.Instance._suspensionContext.Count--;
if (x.Instance._suspensionContext.Count == 0)
{
if (x.Instance.IsDirty)
{
x.Instance.IsDirty = false;
x.Instance.NotifyChanges();
}
x.Instance._suspensionContext = null;
}
}, _suspensionContext));
}
/// <summary>
/// Removes the specified items from the collection without causing a change notification for all items.
/// <para />
/// This method will raise a change notification at the end.
/// </summary>
/// <param name="collection">The collection.</param>
/// <param name="mode">The suspension mode.</param>
/// <exception cref="ArgumentNullException">The <paramref name="collection"/> is <c>null</c>.</exception>
public void RemoveItems(IEnumerable <T> collection, SuspensionMode mode)
{
Argument.IsNotNull("collection", collection);
using (SuspendChangeNotifications(mode))
{
foreach (var item in collection)
{
Remove(item);
}
}
}
/// <summary>
/// Transforms the <see cref="SuspensionMode"/> into its equivalent <see cref="NotifyCollectionChangedAction"/>.
/// </summary>
/// <param name="mode">The suspension mode.</param>
/// <returns>The equivalent <see cref="NotifyCollectionChangedAction"/>.</returns>
private static NotifyCollectionChangedAction ModeToAction(SuspensionMode mode)
{
// Only transform modes Adding and Removing, others fail
switch (mode)
{
case SuspensionMode.Adding: return(NotifyCollectionChangedAction.Add);
case SuspensionMode.Removing: return(NotifyCollectionChangedAction.Remove);
default: throw new ArgumentException($"Wrong mode '{mode}' for constructor.");
}
}
/// <summary>
/// Inserts the elements of the specified collection at the specified index.
/// <para />
/// This method will raise a change notification at the end.
/// </summary>
/// <param name="collection">The collection.</param>
/// <param name="index">The start index.</param>
/// <param name="mode">The suspension mode.</param>
/// <exception cref="ArgumentNullException">The <paramref name="collection"/> is <c>null</c>.</exception>
public virtual void InsertItems(IEnumerable <T> collection, int index, SuspensionMode mode)
{
Argument.IsNotNull("collection", collection);
using (SuspendChangeNotifications(mode))
{
foreach (var item in collection)
{
Insert(index++, item);
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="NotifyRangedCollectionChangedEventArgs"/> class.
/// </summary>
/// <param name="changedItems">The changed items.</param>
/// <param name="indices">The indices.</param>
/// <param name="mode">The suspension mode.</param>
/// <param name="action">The action.</param>
/// <remarks>This is only for use of <see cref="Catel.Collections.SuspensionMode.MixedBash"/>.</remarks>
public NotifyRangedCollectionChangedEventArgs(IList changedItems, IList <int> indices, SuspensionMode mode, NotifyCollectionChangedAction action)
: base(EnsureModeAndAction(mode, action), changedItems, (indices != null && indices.Count != 0) ? indices[0] : -1)
{
Argument.IsNotNull(nameof(changedItems), changedItems);
Argument.IsNotNull(nameof(indices), indices);
// ReSharper disable once PossibleNullReferenceException
Argument.IsNotOutOfRange(nameof(indices), indices.Count, changedItems.Count, changedItems.Count);
ChangedItems = changedItems;
Indices = indices;
SuspensionMode = mode;
}
/// <summary>
/// Adds the specified items to the collection without causing a change notification for all items.
/// <para />
/// This method will raise a change notification at the end.
/// </summary>
/// <param name="collection">The collection.</param>
/// <param name="mode">The suspension mode.</param>
/// <exception cref="ArgumentNullException">The <paramref name="collection"/> is <c>null</c>.</exception>
public void AddItems(IEnumerable collection, SuspensionMode mode)
{
Argument.IsNotNull("collection", collection);
using (SuspendChangeNotifications(mode))
{
foreach (var item in collection)
{
((IList)this).Add(item);
}
}
}
/// <summary>
/// The ensure mode and action.
/// </summary>
/// <param name="mode">The suspension mode.</param>
/// <param name="action">The action.</param>
/// <returns>The <see cref="NotifyCollectionChangedAction"/>.</returns>
private static NotifyCollectionChangedAction EnsureModeAndAction(SuspensionMode mode, NotifyCollectionChangedAction action)
{
// Check for mixed modes except for Mixed, others fail
if (mode == SuspensionMode.Mixed || !mode.IsMixedMode())
{
throw new ArgumentException($"Wrong mode '{mode}' for constructor.");
}
// Check for action Add or Remove, others fail
switch (action)
{
case NotifyCollectionChangedAction.Add:
case NotifyCollectionChangedAction.Remove: return(action);
default: throw new ArgumentException($"Wrong action '{action}' for constructor.");
}
}
/// <summary>
/// Suspends the change notifications until the returned <see cref="IDisposable"/> is disposed.
/// <example>
/// <code>
/// <![CDATA[
/// var fastCollection = new FastBindingList<int>();
/// using (fastCollection.SuspendChangeNotificaftions())
/// {
/// // Adding or removing events inside here will not raise events
/// fastCollection.Add(1);
/// fastCollection.Add(2);
/// fastCollection.Add(3);
///
/// fastCollection.Remove(3);
/// fastCollection.Remove(2);
/// fastCollection.Remove(1);
/// }
/// ]]>
/// </code>
/// </example>
/// </summary>
/// <param name="mode">The suspension Mode.</param>
/// <returns>IDisposable.</returns>
public IDisposable SuspendChangeNotifications(SuspensionMode mode)
{
if (_suspensionContext is null)
{
// Create new context
_suspensionContext = new ExtendedSuspensionContext <T>(mode);
}
else if (_suspensionContext.Mode != mode)
{
throw Log.ErrorAndCreateException <InvalidOperationException>("Cannot change mode during another active suspension.");
}
return(new DisposableToken <FastBindingList <T> >(
this,
x =>
{
if (x.Instance._suspensionContext.Count == 0)
{
x.Instance.RaiseListChangedEvents = false;
x.Instance.IsDirty = true;
}
x.Instance._suspensionContext.Count++;
},
x =>
{
x.Instance._suspensionContext.Count--;
if (x.Instance._suspensionContext.Count == 0)
{
x.Instance.RaiseListChangedEvents = true;
x.Instance.IsDirty = false;
x.Instance.NotifyChanges();
x.Instance._suspensionContext = null;
}
}, _suspensionContext));
}
/// <summary>
/// The is mixed mode.
/// </summary>
/// <param name="suspensionMode">The suspension Mode.</param>
/// <returns><c>True</c> if <see cref="SuspensionMode"/> is one of the mixed modes; otherwise, <c>false</c>.</returns>
public static bool IsMixedMode(this SuspensionMode suspensionMode)
{
return(MixedModes.Contains(suspensionMode));
}
/// <summary>
/// Initializes a new instance of the <see cref="ExtendedSuspensionContext{T}" /> class.
/// </summary>
/// <param name="mode">The suspension mode.</param>
public ExtendedSuspensionContext(SuspensionMode mode)
{
_suspensionMode = mode;
}
/// <summary>
/// Initializes a new instance of the <see cref="SuspensionContext{T}" /> class.
/// </summary>
/// <param name="mode">The suspension mode.</param>
public SuspensionContext(SuspensionMode mode)
{
_suspensionMode = mode;
}
/// <summary>
/// Creates the bash event args list.
/// </summary>
/// <param name="suspensionContext">The suspension context.</param>
/// <param name="suspensionMode">The suspension mode.</param>
/// <typeparam name="T">The type of collection item.</typeparam>
/// <returns>The <see cref="IList{NotifyRangedCollectionChangedEventArgs}"/>.</returns>
private static IList <NotifyRangedCollectionChangedEventArgs> CreateBashEvents <T>(this SuspensionContext <T> suspensionContext, SuspensionMode suspensionMode)
{
var i = 0;
var changedItems = new List <T>();
var changedItemIndices = new List <int>();
var previousAction = (NotifyCollectionChangedAction?)null;
var eventArgsList = new List <NotifyRangedCollectionChangedEventArgs>();
foreach (var action in suspensionContext.MixedActions)
{
// If action changed, create event args for remembered items
if (previousAction.HasValue && action != previousAction.Value)
{
// Create and add event args
eventArgsList.Add(new NotifyRangedCollectionChangedEventArgs(changedItems, changedItemIndices, suspensionMode, previousAction.Value));
// Reset lists
changedItems = new List <T>();
changedItemIndices = new List <int>();
}
// Remember item and index
changedItems.Add(suspensionContext.ChangedItems[i]);
changedItemIndices.Add(suspensionContext.ChangedItemIndices[i]);
// Update to current action
previousAction = action;
i++;
}
// Create event args for last item(s)
if (changedItems.Count != 0 && previousAction != null)
{
eventArgsList.Add(new NotifyRangedCollectionChangedEventArgs(changedItems, changedItemIndices, suspensionMode, previousAction.Value));
}
return(eventArgsList);
}
public new IDisposable SuspendChangeNotifications(SuspensionMode mode)
{
_initialCount = Count;
return(base.SuspendChangeNotifications(mode));
}
