/// <summary>
/// Constructs a observable read only list, which concatenates two observable readonly lists.
/// </summary>
/// <param name="firstCollection"></param>
/// <param name="secondCollection"></param>
/// <param name="notificationScheduler">On this scheduler the notifications are emitted.</param>
public ConcatenatingObservableReadOnlyList(IObservableReadOnlyList <T> firstCollection, IObservableReadOnlyList <T> secondCollection, IScheduler notificationScheduler)
{
_firstBackingList = firstCollection;
_secondBackingList = secondCollection;
ConnectToCollectionChangedOnScheduler(firstCollection, secondCollection, notificationScheduler);
}
/// <summary>
/// Constructs a observable read only list, which concatenates two observable readonly lists.
/// </summary>
/// <param name="firstCollection"></param>
/// <param name="secondCollection"></param>
public ConcatenatingObservableReadOnlyList(IObservableReadOnlyList <T> firstCollection, IObservableReadOnlyList <T> secondCollection)
{
_firstBackingList = firstCollection;
_secondBackingList = secondCollection;
ConnectToCollectionChanged(firstCollection, secondCollection);
}
/// <summary>
/// Constructs a concatenating read only list, which takes a ObservableCollection (second) and another observable read only list (first).
/// </summary>
/// <typeparam name="TB">Item type of the second collection. Should inherit from T.</typeparam>
/// <param name="collectionA">First concatenated collection.</param>
/// <param name="collectionB">Second concatenated collection.</param>
/// <returns>A concatenating read only list, which takes a ObservableCollection and another observable read only list.</returns>
public static ConcatenatingObservableReadOnlyList <T> Concatenate <TB>(IObservableReadOnlyList <T> collectionA,
ObservableCollection <TB> collectionB)
where TB : class, T
{
IObservableReadOnlyList <T> wrapB = new WrappingObservableReadOnlyList <TB>(collectionB);
return(new ConcatenatingObservableReadOnlyList <T>(collectionA, wrapB));
}
/// <summary>
/// Constructs a concatenating read only list, which takes a ObservableCollection (first) and another observable read only list (second).
/// </summary>
/// <typeparam name="TA">Item type of the first collection. Should inherit from T.</typeparam>
/// <param name="collectionA">First concatenated collection.</param>
/// <param name="collectionB">Second concatenated collection.</param>
/// <returns>A concatenating read only list, which takes a ObservableCollection and another observable read only list.</returns>
public static ConcatenatingObservableReadOnlyList <T> Concatenate <TA>(ObservableCollection <TA> collectionA,
IObservableReadOnlyList <T> collectionB)
where TA : class, T
{
IObservableReadOnlyList <T> wrapA = new WrappingObservableReadOnlyList <TA>(collectionA);
return(new ConcatenatingObservableReadOnlyList <T>(wrapA, collectionB));
}
private static void UninitializedCheck(
IObservableReadOnlyList <A> readOnlyList)
{
if (readOnlyList == null)
{
throw new ArgumentNullException(nameof(readOnlyList));
}
Assert.Equal(0, readOnlyList.Count);
}
/// <summary>
/// Constructs a TransformingObservableReadOnlyList synchronizing with an IObservableReadOnlyList source.
/// Intended to be used only by the constructors.
/// </summary>
/// <param name="source">List to synchronize with.</param>
/// <param name="transform">Logic to transform a TSource object to a TResult object.</param>
public TransformingObservableReadOnlyList(IObservableReadOnlyList <TSource> source, Func <TSource, TResult> transform)
{
//The source collection may already have items. Thus, they are transformed and added to the backing list.
foreach (TSource from in source)
{
_backingList.Add(transform(from));
}
ConnectToCollectionChanged(source, transform);
}
private static void StandardCheck(ObservableCollection <A> filledCollection,
IObservableReadOnlyList <A> readOnlyList)
{
Assert.Equal(filledCollection.Count, readOnlyList.Count);
int index = 0;
foreach (A a in readOnlyList)
{
Assert.Same(a, filledCollection[index++]);
}
}
public static ReadOnlyObservableCollection <T> ToReadOnlyObservableCollection <T>(
this IObservableReadOnlyList <T> list)
{
var observableCollection = new ObservableCollection <T>(list);
list.CollectionChanged += (sender, args) =>
{
switch (args.Action)
{
case NotifyCollectionChangedAction.Add:
int i = args.NewStartingIndex;
foreach (T item in args.NewItems.Cast <T>())
{
observableCollection.Insert(i++, item);
}
break;
case NotifyCollectionChangedAction.Remove:
for (int l = 0; l < args.OldItems.Count; l++)
{
observableCollection.RemoveAt(args.OldStartingIndex);
}
break;
case NotifyCollectionChangedAction.Replace:
for (int l = 0; l < args.OldItems.Count; l++)
{
observableCollection.RemoveAt(args.OldStartingIndex);
}
int j = args.NewStartingIndex;
foreach (T item in args.NewItems.Cast <T>())
{
observableCollection.Insert(j++, item);
}
break;
case NotifyCollectionChangedAction.Move:
IList movedItems = new List <T>();
for (int l = 0; l < args.OldItems.Count; l++)
{
T movedItem = observableCollection[args.OldStartingIndex];
movedItems.Add(movedItem);
observableCollection.RemoveAt(args.OldStartingIndex);
}
int k = args.NewStartingIndex;
foreach (T movedItem in movedItems)
{
observableCollection.Insert(k++, movedItem);
}
break;
case NotifyCollectionChangedAction.Reset:
observableCollection.Clear();
break;
default:
throw new Exception("Something unexpected happened with the source collection.");
}
};
return(new ReadOnlyObservableCollection <T>(observableCollection));
}
public static IObservableReadOnlyList <T> Concatenate <T>(
this IObservableReadOnlyList <T> first, ReadOnlyObservableCollection <T> second, IScheduler notificationScheduler)
=> new ConcatenatingObservableReadOnlyList <T>(first, second.ToObservableReadOnlyList(), notificationScheduler);
public static IObservableReadOnlyList <TResult> Transform <TSource, TResult>(
this IObservableReadOnlyList <TSource> source, Func <TSource, TResult> transform, IScheduler notificationScheduler)
=> new TransformingObservableReadOnlyList <TSource, TResult>(source, transform, notificationScheduler);
public static IObservableReadOnlyList <T> Concatenate <T>(
this IObservableReadOnlyList <T> first, ReadOnlyObservableCollection <T> second)
=> new ConcatenatingObservableReadOnlyList <T>(first, second.ToObservableReadOnlyList());
public static IObservableReadOnlyList <T> Concatenate <T>(
this IObservableReadOnlyList <T> first, IObservableReadOnlyList <T> second)
=> new ConcatenatingObservableReadOnlyList <T>(first, second);
public static IObservableReadOnlyList <TResult> Transform <TSource, TResult>(
this IObservableReadOnlyList <TSource> source, Func <TSource, TResult> transform)
=> new TransformingObservableReadOnlyList <TSource, TResult>(source, transform);
public static IObservable <IChange <IListOperation <T> > > AsObservable <T>(
[NotNull] this IObservableReadOnlyList <T> list) =>
list.WhenUpdated.StartWith(new ListInsertBatchOperation <T>(list, 0)).NotNull();
/// <summary>
/// For the sake of completeness. Directly delegates construction to the constructor.
/// </summary>
/// <param name="collectionA">First concatenated collection.</param>
/// <param name="collectionB">Second concatenated collection.</param>
/// <returns>A concatenating read only list, which takes two observable read only list.</returns>
public static ConcatenatingObservableReadOnlyList <T> Concatenate(IObservableReadOnlyList <T> collectionA,
IObservableReadOnlyList <T> collectionB)
{
return(new ConcatenatingObservableReadOnlyList <T>(collectionA, collectionB));
}
