Cross-platform base components for the MVVM pattern. Includes ViewModelBase, RelayCommand, DelegateCommand, SortedCollection, and Table data models. Platform-specific implementations are available in OutWit.Common.MVVM.WPF and OutWit.Common.MVVM.Avalonia packages.
public class MyViewModel : ViewModelBase<IApplicationViewModel>
{
private string m_name = "";
public MyViewModel(IApplicationViewModel appVm) : base(appVm)
{
}
public string Name
{
get => m_name;
set
{
m_name = value;
OnPropertyChanged();
}
}
}
RelayCommand
public class MyViewModel : ViewModelBase<IApplicationViewModel>
{
public RelayCommand SaveCommand { get; }
public MyViewModel(IApplicationViewModel appVm) : base(appVm)
{
SaveCommand = new RelayCommand(
execute: _ => Save(),
canExecute: _ => CanSave());
}
private void Save() { /* Save logic */ }
private bool CanSave() => !string.IsNullOrEmpty(Name);
private void OnNameChanged()
{
SaveCommand.RaiseCanExecuteChanged();
}
}
DelegateCommand<T>
public DelegateCommand<string> SearchCommand { get; }
SearchCommand = new DelegateCommand<string>(
execute: searchText => PerformSearch(searchText),
canExecute: searchText => !string.IsNullOrEmpty(searchText));
SortedCollection
Thread-safe sorted collection with change notifications:
var items = new SortedCollection<int, Item>(x => x.Id);
items.ItemsAdded += (s, added) => Console.WriteLine($"Added {added.Count} items");
items.ItemsRemoved += (s, removed) => Console.WriteLine($"Removed {removed.Count} items");
items.Add(new Item { Id = 1, Name = "First" });
ObservableSortedCollection
Observes property changes in collection items:
var items = new ObservableSortedCollection<int, Item>(x => x.Id);
// Listen for item property changes
items.CollectionContentChanged += (sender, e) =>
{
var item = sender as Item;
Console.WriteLine($"Property {e.PropertyName} changed on item {item?.Id}");
};
items.Add(new Item { Id = 1, Name = "First" });
items[1].Name = "Updated"; // Triggers CollectionContentChanged
SafeObservableCollection with IDispatcher
// Thread-safe collection that marshals notifications to UI thread
var items = new SafeObservableCollection<Item>(dispatcher);
// Safe to call from background thread
await Task.Run(() =>
{
foreach (var item in loadedItems)
{
items.Add(item); // UI updates happen on correct thread
}
});
Platform-Specific Packages
Package
Platform
Features
OutWit.Common.MVVM.WPF
WPF
DependencyProperty source generator, WPF commands, visual tree utilities
Licensed under the Apache License, Version 2.0. See LICENSE.
Attribution (optional)
If you use OutWit.Common.MVVM in a product, a mention is appreciated (but not required), for example:
"Powered by OutWit.Common.MVVM (https://ratner.io/)".
Trademark / Project name
"OutWit" and the OutWit logo are used to identify the official project by Dmitry Ratner.
You may:
refer to the project name in a factual way (e.g., "built with OutWit.Common.MVVM");
use the name to indicate compatibility (e.g., "OutWit.Common.MVVM-compatible").
You may not:
use "OutWit.Common.MVVM" as the name of a fork or a derived product in a way that implies it is the official project;
use the OutWit.Common.MVVM logo to promote forks or derived products without permission.