It doesn’t claim to include the old items, because Reset doesn’t mean that the list has been cleared It means that some dramatic thing has taken place, and the cost of working out the add/removes would most likely exceed the cost of just re-scanning the list from scratch… so that’s what you should do. MSDN … Read more
As of .net framwork 4.5 you can use native collection synchronization. BindingOperations.EnableCollectionSynchronization(YourCollection, YourLockObject); YourLockObject is instance of any object e.g. new Object();. Use one per collection. This eliminates the need of some special class or anything. Just enable and enjoy 😉 [edit] As stated in the comments by Mark and Ed (thanks for clarifying!), this … Read more
Here is how you would attach/detach to each item’s PropertyChanged event. ObservableCollection<INotifyPropertyChanged> items = new ObservableCollection<INotifyPropertyChanged>(); items.CollectionChanged += items_CollectionChanged; static void items_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e) { if (e.OldItems != null) { foreach (INotifyPropertyChanged item in e.OldItems) item.PropertyChanged -= item_PropertyChanged; } if (e.NewItems != null) { foreach (INotifyPropertyChanged item in e.NewItems) item.PropertyChanged += item_PropertyChanged; } } … Read more
The best way to solve this is to pass the Dispatcher object to the start method of the background thread. void DoBackgroundOperation(ObservableCollection<SomeType> col) { var dispatcher = Dispatcher.CurrentDispatcher; ThreadStart start = () => BackgroundStart(dispatcher, col); var t = new Thread(start); t.Start(); } private static void BackgroundStart( Dispatcher dispatcher, ObservableCollection<SomeType> col) { … SomeType t = … Read more
The Microsoft ParallelExtensionsExtras provides this class which is not only observable but is also concurrent: Now available via Nuget: https://www.nuget.org/packages/MSFT.ParallelExtensionsExtras/ The source code was recently updated for .NET Standard 2.1 on 05/11/2020 and the source code is available at GitHub: https://github.com/dotnet/samples/tree/master/csharp/parallel/ParallelExtensionsExtras Note that some of the features are now a part of newer .NET frameworks. … Read more
ColinE is right with all his informations. I only want to add my subclass of ObservableCollection that I use for this specific case. public class SmartCollection<T> : ObservableCollection<T> { public SmartCollection() : base() { } public SmartCollection(IEnumerable<T> collection) : base(collection) { } public SmartCollection(List<T> list) : base(list) { } public void AddRange(IEnumerable<T> range) { foreach … Read more
ObservableCollection can be fast, if it wants to. 🙂 The code below is a very good example of a thread safe, faster observable collection and you can extend it further to your wish. using System.Collections.Specialized; public class FastObservableCollection<T> : ObservableCollection<T> { private readonly object locker = new object(); /// <summary> /// This private variable holds … Read more
This simple extension worked beautifully for me. I just had to make sure that MyObject was IComparable. When the sort method is called on the observable collection of MyObjects, the CompareTo method on MyObject is called, which calls my Logical Sort method. While it doesn’t have all the bells and whistles of the rest of … Read more
Introduction Basically, if there is a need to display a sorted collection, please consider using the CollectionViewSource class: assign (“bind”) its Source property to the source collection — an instance of the ObservableCollection<T> class. The idea is that CollectionViewSource class provides an instance of the CollectionView class. This is kind of “projection” of the original … Read more
The spot you have commented as // Code to trig on item change… will only trigger when the collection object gets changed, such as when it gets set to a new object, or set to null. With your current implementation of TrulyObservableCollection, to handle the property changed events of your collection, register something to the … Read more