Shows how to implement INotifyPropertyChanged,ObservableProperty and RelayCommand
Unfortunately , not yet a separate package just for those.
Also, this show that RSCG could generate multiple partial declarations
This is how you can use CommunityToolkit.Mvvm .
The code that you start with is
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ImplicitUsings>enable</ImplicitUsings>
<Nullable>enable</Nullable>
</PropertyGroup>
<ItemGroup>
<PackageReference Include="CommunityToolkit.Mvvm" Version="8.2.0" />
</ItemGroup>
<PropertyGroup>
<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
</PropertyGroup>
</Project>
The code that you will use is
// See https://aka.ms/new-console-template for more information
using test;
Console.WriteLine("Hello, World!");
MyViewModel myViewModel = new();
myViewModel.Name = "Andrei";
var x=myViewModel.SayHelloCommand;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
namespace test;
[INotifyPropertyChanged]
public partial class MyViewModel
{
[ObservableProperty]
private string? name;
[RelayCommand]
private void SayHello()
{
Console.WriteLine("Hello");
}
}
The code that is generated is
// <auto-generated/>
#pragma warning disable
#nullable enable
namespace test
{
/// <inheritdoc/>
partial class MyViewModel : global::System.ComponentModel.INotifyPropertyChanged
{
/// <inheritdoc cref = "global::System.ComponentModel.INotifyPropertyChanged.PropertyChanged"/>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
public event global::System.ComponentModel.PropertyChangedEventHandler? PropertyChanged;
/// <summary>
/// Raises the <see cref = "PropertyChanged"/> event.
/// </summary>
/// <param name = "e">The input <see cref = "global::System.ComponentModel.PropertyChangedEventArgs"/> instance.</param>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected virtual void OnPropertyChanged(global::System.ComponentModel.PropertyChangedEventArgs e)
{
PropertyChanged?.Invoke(this, e);
}
/// <summary>
/// Raises the <see cref = "PropertyChanged"/> event.
/// </summary>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected void OnPropertyChanged([global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
OnPropertyChanged(new global::System.ComponentModel.PropertyChangedEventArgs(propertyName));
}
/// <summary>
/// Compares the current and new values for a given property. If the value has changed, updates
/// the property with the new value, then raises the <see cref = "PropertyChanged"/> event.
/// </summary>
/// <typeparam name = "T">The type of the property that changed.</typeparam>
/// <param name = "field">The field storing the property's value.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
/// <remarks>
/// The <see cref = "PropertyChanged"/> event is not raised if the current and new value for the target property are the same.
/// </remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetProperty<T>([global::System.Diagnostics.CodeAnalysis.NotNullIfNotNull("newValue")] ref T field, T newValue, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
if (global::System.Collections.Generic.EqualityComparer<T>.Default.Equals(field, newValue))
{
return false;
}
field = newValue;
OnPropertyChanged(propertyName);
return true;
}
/// <summary>
/// Compares the current and new values for a given property. If the value has changed, updates
/// the property with the new value, then raises the <see cref = "PropertyChanged"/> event.
/// See additional notes about this overload in <see cref = "SetProperty{T}(ref T, T, string)"/>.
/// </summary>
/// <typeparam name = "T">The type of the property that changed.</typeparam>
/// <param name = "field">The field storing the property's value.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "comparer">The <see cref = "global::System.Collections.Generic.IEqualityComparer{T}"/> instance to use to compare the input values.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetProperty<T>([global::System.Diagnostics.CodeAnalysis.NotNullIfNotNull("newValue")] ref T field, T newValue, global::System.Collections.Generic.IEqualityComparer<T> comparer, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
if (comparer.Equals(field, newValue))
{
return false;
}
field = newValue;
OnPropertyChanged(propertyName);
return true;
}
/// <summary>
/// Compares the current and new values for a given property. If the value has changed, updates
/// the property with the new value, then raises the <see cref = "PropertyChanged"/> event.
/// This overload is much less efficient than <see cref = "SetProperty{T}(ref T, T, string)"/> and it
/// should only be used when the former is not viable (eg. when the target property being
/// updated does not directly expose a backing field that can be passed by reference).
/// For performance reasons, it is recommended to use a stateful callback if possible through
/// the <see cref = "SetProperty{TModel, T}(T, T, TModel, global::System.Action{TModel, T}, string? )"/> whenever possible
/// instead of this overload, as that will allow the C# compiler to cache the input callback and
/// reduce the memory allocations. More info on that overload are available in the related XML
/// docs. This overload is here for completeness and in cases where that is not applicable.
/// </summary>
/// <typeparam name = "T">The type of the property that changed.</typeparam>
/// <param name = "oldValue">The current property value.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "callback">A callback to invoke to update the property value.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
/// <remarks>
/// The <see cref = "PropertyChanged"/> event is not raised if the current and new value for the target property are the same.
/// </remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetProperty<T>(T oldValue, T newValue, global::System.Action<T> callback, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
if (global::System.Collections.Generic.EqualityComparer<T>.Default.Equals(oldValue, newValue))
{
return false;
}
callback(newValue);
OnPropertyChanged(propertyName);
return true;
}
/// <summary>
/// Compares the current and new values for a given property. If the value has changed, updates
/// the property with the new value, then raises the <see cref = "PropertyChanged"/> event.
/// See additional notes about this overload in <see cref = "SetProperty{T}(T, T, global::System.Action{T}, string)"/>.
/// </summary>
/// <typeparam name = "T">The type of the property that changed.</typeparam>
/// <param name = "oldValue">The current property value.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "comparer">The <see cref = "global::System.Collections.Generic.IEqualityComparer{T}"/> instance to use to compare the input values.</param>
/// <param name = "callback">A callback to invoke to update the property value.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetProperty<T>(T oldValue, T newValue, global::System.Collections.Generic.IEqualityComparer<T> comparer, global::System.Action<T> callback, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
if (comparer.Equals(oldValue, newValue))
{
return false;
}
callback(newValue);
OnPropertyChanged(propertyName);
return true;
}
/// <summary>
/// Compares the current and new values for a given nested property. If the value has changed,
/// updates the property and then raises the <see cref = "PropertyChanged"/> event.
/// The behavior mirrors that of <see cref = "SetProperty{T}(ref T, T, string)"/>,
/// with the difference being that this method is used to relay properties from a wrapped model in the
/// current instance. This type is useful when creating wrapping, bindable objects that operate over
/// models that lack support for notification (eg. for CRUD operations).
/// Suppose we have this model (eg. for a database row in a table):
/// <code>
/// public class Person
/// {
/// public string Name { get; set; }
/// }
/// </code>
/// We can then use a property to wrap instances of this type into our observable model (which supports
/// notifications), injecting the notification to the properties of that model, like so:
/// <code>
/// [INotifyPropertyChanged]
/// public partial class BindablePerson
/// {
/// public Model { get; }
///
/// public BindablePerson(Person model)
/// {
/// Model = model;
/// }
///
/// public string Name
/// {
/// get => Model.Name;
/// set => Set(Model.Name, value, Model, (model, name) => model.Name = name);
/// }
/// }
/// </code>
/// This way we can then use the wrapping object in our application, and all those "proxy" properties will
/// also raise notifications when changed. Note that this method is not meant to be a replacement for
/// <see cref = "SetProperty{T}(ref T, T, string)"/>, and it should only be used when relaying properties to a model that
/// doesn't support notifications, and only if you can't implement notifications to that model directly (eg. by having
/// it implement <see cref = "global::System.ComponentModel.INotifyPropertyChanged"/>). The syntax relies on passing the target model and a stateless callback
/// to allow the C# compiler to cache the function, which results in much better performance and no memory usage.
/// </summary>
/// <typeparam name = "TModel">The type of model whose property (or field) to set.</typeparam>
/// <typeparam name = "T">The type of property (or field) to set.</typeparam>
/// <param name = "oldValue">The current property value.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "model">The model containing the property being updated.</param>
/// <param name = "callback">The callback to invoke to set the target property value, if a change has occurred.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
/// <remarks>
/// The <see cref = "PropertyChanged"/> event is not raised if the current and new value for the target property are the same.
/// </remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetProperty<TModel, T>(T oldValue, T newValue, TModel model, global::System.Action<TModel, T> callback, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
where TModel : class
{
if (global::System.Collections.Generic.EqualityComparer<T>.Default.Equals(oldValue, newValue))
{
return false;
}
callback(model, newValue);
OnPropertyChanged(propertyName);
return true;
}
/// <summary>
/// Compares the current and new values for a given nested property. If the value has changed,
/// updates the property and then raises the <see cref = "PropertyChanged"/> event.
/// The behavior mirrors that of <see cref = "SetProperty{T}(ref T, T, string)"/>,
/// with the difference being that this method is used to relay properties from a wrapped model in the
/// current instance. See additional notes about this overload in <see cref = "SetProperty{TModel, T}(T, T, TModel, global::System.Action{TModel, T}, string)"/>.
/// </summary>
/// <typeparam name = "TModel">The type of model whose property (or field) to set.</typeparam>
/// <typeparam name = "T">The type of property (or field) to set.</typeparam>
/// <param name = "oldValue">The current property value.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "comparer">The <see cref = "global::System.Collections.Generic.IEqualityComparer{T}"/> instance to use to compare the input values.</param>
/// <param name = "model">The model containing the property being updated.</param>
/// <param name = "callback">The callback to invoke to set the target property value, if a change has occurred.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetProperty<TModel, T>(T oldValue, T newValue, global::System.Collections.Generic.IEqualityComparer<T> comparer, TModel model, global::System.Action<TModel, T> callback, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
where TModel : class
{
if (comparer.Equals(oldValue, newValue))
{
return false;
}
callback(model, newValue);
OnPropertyChanged(propertyName);
return true;
}
/// <summary>
/// Compares the current and new values for a given field (which should be the backing field for a property).
/// If the value has changed, updates the field and then raises the <see cref = "PropertyChanged"/> event.
/// The behavior mirrors that of <see cref = "SetProperty{T}(ref T, T, string)"/>, with the difference being that
/// this method will also monitor the new value of the property (a generic <see cref = "global::System.Threading.Tasks.Task"/>) and will also
/// raise the <see cref = "PropertyChanged"/> again for the target property when it completes.
/// This can be used to update bindings observing that <see cref = "global::System.Threading.Tasks.Task"/> or any of its properties.
/// This method and its overload specifically rely on the <see cref = "TaskNotifier"/> type, which needs
/// to be used in the backing field for the target <see cref = "global::System.Threading.Tasks.Task"/> property. The field doesn't need to be
/// initialized, as this method will take care of doing that automatically. The <see cref = "TaskNotifier"/>
/// type also includes an implicit operator, so it can be assigned to any <see cref = "global::System.Threading.Tasks.Task"/> instance directly.
/// Here is a sample property declaration using this method:
/// <code>
/// private TaskNotifier myTask;
///
/// public Task MyTask
/// {
/// get => myTask;
/// private set => SetAndNotifyOnCompletion(ref myTask, value);
/// }
/// </code>
/// </summary>
/// <param name = "taskNotifier">The field notifier to modify.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
/// <remarks>
/// The <see cref = "PropertyChanged"/> event is not raised if the current and new value for the target property are
/// the same. The return value being <see langword="true"/> only indicates that the new value being assigned to
/// <paramref name = "taskNotifier"/> is different than the previous one, and it does not mean the new
/// <see cref = "global::System.Threading.Tasks.Task"/> instance passed as argument is in any particular state.
/// </remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetPropertyAndNotifyOnCompletion([global::System.Diagnostics.CodeAnalysis.NotNull] ref TaskNotifier? taskNotifier, global::System.Threading.Tasks.Task? newValue, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
return SetPropertyAndNotifyOnCompletion(taskNotifier ??= new TaskNotifier(), newValue, null, propertyName);
}
/// <summary>
/// Compares the current and new values for a given field (which should be the backing field for a property).
/// If the value has changed, updates the field and then raises the <see cref = "PropertyChanged"/> event.
/// This method is just like <see cref = "SetPropertyAndNotifyOnCompletion(ref TaskNotifier, global::System.Threading.Tasks.Task, string)"/>,
/// with the difference being an extra <see cref = "global::System.Action{T}"/> parameter with a callback being invoked
/// either immediately, if the new task has already completed or is <see langword="null"/>, or upon completion.
/// </summary>
/// <param name = "taskNotifier">The field notifier to modify.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "callback">A callback to invoke to update the property value.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
/// <remarks>
/// The <see cref = "PropertyChanged"/> event is not raised if the current and new value for the target property are the same.
/// </remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetPropertyAndNotifyOnCompletion([global::System.Diagnostics.CodeAnalysis.NotNull] ref TaskNotifier? taskNotifier, global::System.Threading.Tasks.Task? newValue, global::System.Action<global::System.Threading.Tasks.Task?> callback, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
return SetPropertyAndNotifyOnCompletion(taskNotifier ??= new TaskNotifier(), newValue, callback, propertyName);
}
/// <summary>
/// Compares the current and new values for a given field (which should be the backing field for a property).
/// If the value has changed, updates the field and then raises the <see cref = "PropertyChanged"/> event.
/// The behavior mirrors that of <see cref = "SetProperty{T}(ref T, T, string)"/>, with the difference being that
/// this method will also monitor the new value of the property (a generic <see cref = "global::System.Threading.Tasks.Task"/>) and will also
/// raise the <see cref = "PropertyChanged"/> again for the target property when it completes.
/// This can be used to update bindings observing that <see cref = "global::System.Threading.Tasks.Task"/> or any of its properties.
/// This method and its overload specifically rely on the <see cref = "TaskNotifier{T}"/> type, which needs
/// to be used in the backing field for the target <see cref = "global::System.Threading.Tasks.Task"/> property. The field doesn't need to be
/// initialized, as this method will take care of doing that automatically. The <see cref = "TaskNotifier{T}"/>
/// type also includes an implicit operator, so it can be assigned to any <see cref = "global::System.Threading.Tasks.Task"/> instance directly.
/// Here is a sample property declaration using this method:
/// <code>
/// private TaskNotifier<int> myTask;
///
/// public Task<int> MyTask
/// {
/// get => myTask;
/// private set => SetAndNotifyOnCompletion(ref myTask, value);
/// }
/// </code>
/// </summary>
/// <typeparam name = "T">The type of result for the <see cref = "global::System.Threading.Tasks.Task{TResult}"/> to set and monitor.</typeparam>
/// <param name = "taskNotifier">The field notifier to modify.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
/// <remarks>
/// The <see cref = "PropertyChanged"/> event is not raised if the current and new value for the target property are
/// the same. The return value being <see langword="true"/> only indicates that the new value being assigned to
/// <paramref name = "taskNotifier"/> is different than the previous one, and it does not mean the new
/// <see cref = "global::System.Threading.Tasks.Task{TResult}"/> instance passed as argument is in any particular state.
/// </remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetPropertyAndNotifyOnCompletion<T>([global::System.Diagnostics.CodeAnalysis.NotNull] ref TaskNotifier<T>? taskNotifier, global::System.Threading.Tasks.Task<T>? newValue, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
return SetPropertyAndNotifyOnCompletion(taskNotifier ??= new TaskNotifier<T>(), newValue, null, propertyName);
}
/// <summary>
/// Compares the current and new values for a given field (which should be the backing field for a property).
/// If the value has changed, updates the field and then raises the <see cref = "PropertyChanged"/> event.
/// This method is just like <see cref = "SetPropertyAndNotifyOnCompletion{T}(ref TaskNotifier{T}, global::System.Threading.Tasks.Task{T}, string)"/>,
/// with the difference being an extra <see cref = "global::System.Action{T}"/> parameter with a callback being invoked
/// either immediately, if the new task has already completed or is <see langword="null"/>, or upon completion.
/// </summary>
/// <typeparam name = "T">The type of result for the <see cref = "global::System.Threading.Tasks.Task{TResult}"/> to set and monitor.</typeparam>
/// <param name = "taskNotifier">The field notifier to modify.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "callback">A callback to invoke to update the property value.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
/// <remarks>
/// The <see cref = "PropertyChanged"/> event is not raised if the current and new value for the target property are the same.
/// </remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected bool SetPropertyAndNotifyOnCompletion<T>([global::System.Diagnostics.CodeAnalysis.NotNull] ref TaskNotifier<T>? taskNotifier, global::System.Threading.Tasks.Task<T>? newValue, global::System.Action<global::System.Threading.Tasks.Task<T>?> callback, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
{
return SetPropertyAndNotifyOnCompletion(taskNotifier ??= new TaskNotifier<T>(), newValue, callback, propertyName);
}
/// <summary>
/// Implements the notification logic for the related methods.
/// </summary>
/// <typeparam name = "TTask">The type of <see cref = "global::System.Threading.Tasks.Task"/> to set and monitor.</typeparam>
/// <param name = "taskNotifier">The field notifier.</param>
/// <param name = "newValue">The property's value after the change occurred.</param>
/// <param name = "callback">(optional) A callback to invoke to update the property value.</param>
/// <param name = "propertyName">(optional) The name of the property that changed.</param>
/// <returns><see langword="true"/> if the property was changed, <see langword="false"/> otherwise.</returns>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
private bool SetPropertyAndNotifyOnCompletion<TTask>(ITaskNotifier<TTask> taskNotifier, TTask? newValue, global::System.Action<TTask?>? callback, [global::System.Runtime.CompilerServices.CallerMemberName] string? propertyName = null)
where TTask : global::System.Threading.Tasks.Task
{
if (ReferenceEquals(taskNotifier.Task, newValue))
{
return false;
}
bool isAlreadyCompletedOrNull = newValue?.IsCompleted ?? true;
taskNotifier.Task = newValue;
OnPropertyChanged(propertyName);
if (isAlreadyCompletedOrNull)
{
if (callback != null)
{
callback(newValue);
}
return true;
}
async void MonitorTask()
{
await global::CommunityToolkit.Mvvm.ComponentModel.__Internals.__TaskExtensions.GetAwaitableWithoutEndValidation(newValue!);
if (ReferenceEquals(taskNotifier.Task, newValue))
{
OnPropertyChanged(propertyName);
}
if (callback != null)
{
callback(newValue);
}
}
MonitorTask();
return true;
}
/// <summary>
/// An interface for task notifiers of a specified type.
/// </summary>
/// <typeparam name = "TTask">The type of value to store.</typeparam>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
private interface ITaskNotifier<TTask>
where TTask : global::System.Threading.Tasks.Task
{
/// <summary>
/// Gets or sets the wrapped <typeparamref name = "TTask"/> value.
/// </summary>
TTask? Task { get; set; }
}
/// <summary>
/// A wrapping class that can hold a <see cref = "global::System.Threading.Tasks.Task"/> value.
/// </summary>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected sealed class TaskNotifier : ITaskNotifier<global::System.Threading.Tasks.Task>
{
/// <summary>
/// Initializes a new instance of the <see cref = "TaskNotifier"/> class.
/// </summary>
internal TaskNotifier()
{
}
private global::System.Threading.Tasks.Task? task;
/// <inheritdoc/>
global::System.Threading.Tasks.Task? ITaskNotifier<global::System.Threading.Tasks.Task>.Task { get => this.task; set => this.task = value; }
/// <summary>
/// Unwraps the <see cref = "global::System.Threading.Tasks.Task"/> value stored in the current instance.
/// </summary>
/// <param name = "notifier">The input <see cref = "TaskNotifier{TTask}"/> instance.</param>
public static implicit operator global::System.Threading.Tasks.Task? (TaskNotifier? notifier)
{
return notifier?.task;
}
}
/// <summary>
/// A wrapping class that can hold a <see cref = "global::System.Threading.Tasks.Task{T}"/> value.
/// </summary>
/// <typeparam name = "T">The type of value for the wrapped <see cref = "global::System.Threading.Tasks.Task{T}"/> instance.</typeparam>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.INotifyPropertyChangedGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
protected sealed class TaskNotifier<T> : ITaskNotifier<global::System.Threading.Tasks.Task<T>>
{
/// <summary>
/// Initializes a new instance of the <see cref = "TaskNotifier{TTask}"/> class.
/// </summary>
internal TaskNotifier()
{
}
private global::System.Threading.Tasks.Task<T>? task;
/// <inheritdoc/>
global::System.Threading.Tasks.Task<T>? ITaskNotifier<global::System.Threading.Tasks.Task<T>>.Task { get => this.task; set => this.task = value; }
/// <summary>
/// Unwraps the <see cref = "global::System.Threading.Tasks.Task{T}"/> value stored in the current instance.
/// </summary>
/// <param name = "notifier">The input <see cref = "TaskNotifier{TTask}"/> instance.</param>
public static implicit operator global::System.Threading.Tasks.Task<T>? (TaskNotifier<T>? notifier)
{
return notifier?.task;
}
}
}
}
// <auto-generated/>
#pragma warning disable
#nullable enable
namespace test
{
/// <inheritdoc/>
partial class MyViewModel
{
/// <inheritdoc cref="name"/>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.ObservablePropertyGenerator", "8.2.0.0")]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
public string? Name
{
get => name;
set
{
if (!global::System.Collections.Generic.EqualityComparer<string?>.Default.Equals(name, value))
{
OnNameChanging(value);
OnNameChanging(default, value);
name = value;
OnNameChanged(value);
OnNameChanged(default, value);
OnPropertyChanged(global::CommunityToolkit.Mvvm.ComponentModel.__Internals.__KnownINotifyPropertyChangedArgs.Name);
}
}
}
/// <summary>Executes the logic for when <see cref="Name"/> is changing.</summary>
/// <param name="value">The new property value being set.</param>
/// <remarks>This method is invoked right before the value of <see cref="Name"/> is changed.</remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.ObservablePropertyGenerator", "8.2.0.0")]
partial void OnNameChanging(string? value);
/// <summary>Executes the logic for when <see cref="Name"/> is changing.</summary>
/// <param name="oldValue">The previous property value that is being replaced.</param>
/// <param name="newValue">The new property value being set.</param>
/// <remarks>This method is invoked right before the value of <see cref="Name"/> is changed.</remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.ObservablePropertyGenerator", "8.2.0.0")]
partial void OnNameChanging(string? oldValue, string? newValue);
/// <summary>Executes the logic for when <see cref="Name"/> just changed.</summary>
/// <param name="value">The new property value that was set.</param>
/// <remarks>This method is invoked right after the value of <see cref="Name"/> is changed.</remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.ObservablePropertyGenerator", "8.2.0.0")]
partial void OnNameChanged(string? value);
/// <summary>Executes the logic for when <see cref="Name"/> just changed.</summary>
/// <param name="oldValue">The previous property value that was replaced.</param>
/// <param name="newValue">The new property value that was set.</param>
/// <remarks>This method is invoked right after the value of <see cref="Name"/> is changed.</remarks>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.ObservablePropertyGenerator", "8.2.0.0")]
partial void OnNameChanged(string? oldValue, string? newValue);
}
}
// <auto-generated/>
#pragma warning disable
#nullable enable
namespace CommunityToolkit.Mvvm.ComponentModel.__Internals
{
/// <summary>
/// A helper type providing cached, reusable <see cref="global::System.ComponentModel.PropertyChangedEventArgs"/> instances
/// for all properties generated with <see cref="global::CommunityToolkit.Mvvm.ComponentModel.ObservablePropertyAttribute"/>.
/// </summary>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.ObservablePropertyGenerator", "8.2.0.0")]
[global::System.Diagnostics.DebuggerNonUserCode]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
[global::System.ComponentModel.EditorBrowsable(global::System.ComponentModel.EditorBrowsableState.Never)]
[global::System.Obsolete("This type is not intended to be used directly by user code")]
internal static class __KnownINotifyPropertyChangedArgs
{
/// <summary>The cached <see cref="global::System.ComponentModel.PropertyChangedEventArgs"/> instance for all "Name" generated properties.</summary>
[global::System.ComponentModel.EditorBrowsable(global::System.ComponentModel.EditorBrowsableState.Never)]
[global::System.Obsolete("This field is not intended to be referenced directly by user code")]
public static readonly global::System.ComponentModel.PropertyChangedEventArgs Name = new global::System.ComponentModel.PropertyChangedEventArgs("Name");
}
}
// <auto-generated/>
#pragma warning disable
#nullable enable
namespace test
{
/// <inheritdoc/>
partial class MyViewModel
{
/// <summary>The backing field for <see cref="SayHelloCommand"/>.</summary>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.RelayCommandGenerator", "8.2.0.0")]
private global::CommunityToolkit.Mvvm.Input.RelayCommand? sayHelloCommand;
/// <summary>Gets an <see cref="global::CommunityToolkit.Mvvm.Input.IRelayCommand"/> instance wrapping <see cref="SayHello"/>.</summary>
[global::System.CodeDom.Compiler.GeneratedCode("CommunityToolkit.Mvvm.SourceGenerators.RelayCommandGenerator", "8.2.0.0")]
[global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
public global::CommunityToolkit.Mvvm.Input.IRelayCommand SayHelloCommand => sayHelloCommand ??= new global::CommunityToolkit.Mvvm.Input.RelayCommand(new global::System.Action(SayHello));
}
}
Code and pdf at
https://ignatandrei.github.io/RSCG_Examples/v2/docs/CommunityToolkit.Mvvm
