ATC.Net WPF, WinUI, and Avalonia

This is a base libraries for building WPF, WinUI, or Avalonia application with the MVVM design pattern.

🎁 Key Features

🏗️ MVVM Foundation

• ViewModelBase - Base class with INotifyPropertyChanged
• MainWindowViewModelBase - Main window lifecycle management
• ViewModelDialogBase - Dialog-specific ViewModels
• ObservableObject - Lightweight observable pattern

⚡ Commands

• RelayCommand / RelayCommand<T> - Synchronous commands with CanExecute support
• RelayCommandAsync / RelayCommandAsync<T> - Async/await commands for responsive UIs
• Automatic CanExecute refresh - Commands automatically update UI state
• Error handling support - Built-in IErrorHandler interface for graceful error management

🔔 Messaging System

Decouple your ViewModels with a powerful messaging infrastructure:

• Messenger - Central message bus for app-wide communication
• GenericMessage<T> - Send typed messages between components
• NotificationMessage - Simple notifications with optional callbacks
• PropertyChangedMessage<T> - Broadcast property changes across ViewModels

Perfect for scenarios like:

• Cross-ViewModel communication without direct references
• Event aggregation patterns
• Plugin architectures
• Loosely-coupled component communication

// Send a message
Messenger.Default.Send(new GenericMessage<User>(currentUser));

// Receive a message
Messenger.Default.Register<GenericMessage<User>>(this, msg =>
{
    var user = msg.Content;
    // Handle the user...
});

Learn more: Messaging System Documentation

🎨 Value Converters

Extensive collection of ready-to-use XAML converters for WPF, WinUI, and Avalonia:

Bool Converters

• BoolToInverseBoolValueConverter
• BoolToVisibilityCollapsedValueConverter
• BoolToVisibilityVisibleValueConverter
• BoolToWidthValueConverter
• MultiBoolToBoolValueConverter (AND/OR logic)
• MultiBoolToVisibilityVisibleValueConverter

String Converters

• StringNullOrEmptyToBoolValueConverter
• StringNullOrEmptyToInverseBoolValueConverter
• StringNullOrEmptyToVisibilityVisibleValueConverter
• StringNullOrEmptyToVisibilityCollapsedValueConverter
• ToLowerValueConverter / ToUpperValueConverter

See detailed Value Converters documentation

⚙️ Source Generators

Eliminate boilerplate with powerful code generation:

• [ObservableProperty] - Auto-generate properties with change notification
• [RelayCommand] - Auto-generate command properties from methods
• [DependencyProperty] (WPF) - Auto-generate dependency properties
• [AttachedProperty] (WPF) - Auto-generate attached properties
• [RoutedEvent] (WPF) - Auto-generate routed events

Learn more about each generator:

• SourceGenerators for AttachedProperties
• SourceGenerators for DependencyProperties
• SourceGenerators for RoutedEvents
• SourceGenerators for ViewModel

🚀 Performance Optimizations

• BooleanBoxes - Cached boolean boxing for reduced memory allocations
• WeakAction/WeakFunc - Memory-leak prevention for event handlers and callbacks
• PropertyDefaultValueConstants - Shared default values for common property types

🔧 Utilities

• DesignModeHelper - Detect design-time vs runtime for better designer experience
• Base Converter Classes - ValueConverterBase and MultiValueConverterBase for creating custom converters
• Error Handling - IErrorHandler interface for centralized command error management

🚀 Quick Start

Installation

Install via NuGet Package Manager or .NET CLI:

For WPF:

dotnet add package Atc.XamlToolkit.Wpf

For WinUI:

dotnet add package Atc.XamlToolkit.WinUI

For Avalonia:

dotnet add package Atc.XamlToolkit.Avalonia

Basic Usage

// Create a ViewModel with source-generated properties and commands
public partial class MainViewModel : ViewModelBase
{
    [ObservableProperty]
    private string userName;

    [ObservableProperty]
    private bool isLoading;

    [RelayCommand]
    private async Task LoadDataAsync()
    {
        IsLoading = true;
        // Load data...
        IsLoading = false;
    }
}

📖 Read the full Getting Started Guide for a complete walkthrough.

Requirements

• .NET >= 9.0.202 - SDK
• .NET 9 - Runtime for Avalonia
• .NET 9 - Desktop Runtime for WPF
• .NET 9 - Desktop Runtime for WinUI 3

NuGet Packages Provided in this Repository

Nuget package	Description	Dependencies
	Base package with ViewModelBase, ObservableObject	Atc & Atc.XamlToolkit.SourceGenerators
	RelayCommand, MainWindowViewModelBase for WPF	Atc.XamlToolkit.SourceGenerators
	RelayCommand, MainWindowViewModelBase for WinUI	Atc.XamlToolkit
	RelayCommand, MainWindowViewModelBase for Avalonia	Atc.XamlToolkit

📚 Documentation

Get Started

• Getting Started Guide - Complete walkthrough for beginners

Core Concepts

• MVVM Framework - ViewModels, Commands, and MVVM patterns
• Messaging System - Decoupled communication between components
• Source Generators - Eliminate boilerplate code

Advanced Topics

• Value Converters - Complete converter reference
• Performance Optimizations - BooleanBoxes, WeakAction, and more
• Utilities and Helpers - DesignModeHelper, base classes, and utilities

Platform-Specific (WPF Only)

• Dependency Properties - Auto-generate dependency properties
• Attached Properties - Auto-generate attached properties
• Routed Events - Auto-generate routed events

Source Generator Examples

Example for ViewModel classes with source generation:

For more details, see the MVVM section.

🎯 Complete Feature List

Core MVVM Components

Component	Description	Package
ViewModelBase	Base ViewModel with INotifyPropertyChanged	Atc.XamlToolkit
MainWindowViewModelBase	Main window lifecycle management	Atc.XamlToolkit.Wpf/WinUI/Avalonia
ViewModelDialogBase	Dialog-specific ViewModels	Atc.XamlToolkit
ObservableObject	Lightweight observable pattern	Atc.XamlToolkit

Commands

Command	Description	Async Support
RelayCommand	Synchronous command	No
RelayCommand<T>	Synchronous command with parameter	No
RelayCommandAsync	Asynchronous command	Yes
RelayCommandAsync<T>	Asynchronous command with parameter	Yes

All commands support:

• ✅ CanExecute with automatic refresh
• ✅ Error handling via IErrorHandler
• ✅ Auto-generation via [RelayCommand] attribute

Messaging System

Type	Purpose
Messenger	Central message bus
GenericMessage<T>	Typed message passing
NotificationMessage	String-based notifications
NotificationMessageAction	Messages with callbacks
NotificationMessageAction<T>	Messages with parameterized callbacks
PropertyChangedMessage<T>	Property change broadcasts
NotificationMessageWithCallback	Generic callback support

Source Generators

Generator	Platform	Description
[ObservableProperty]	WPF, WinUI, Avalonia	Auto-generate observable properties
[RelayCommand]	WPF, WinUI, Avalonia	Auto-generate command properties
[DependencyProperty]	WPF only	Auto-generate dependency properties
[AttachedProperty]	WPF only	Auto-generate attached properties
[RoutedEvent]	WPF only	Auto-generate routed events

Value Converters

Bool Converters (WPF, WinUI & Avalonia):

• BoolToInverseBoolValueConverter
• BoolToVisibilityCollapsedValueConverter
• BoolToVisibilityVisibleValueConverter
• BoolToWidthValueConverter
• MultiBoolToBoolValueConverter
• MultiBoolToVisibilityVisibleValueConverter

String Converters (WPF, WinUI & Avalonia):

• StringNullOrEmptyToBoolValueConverter
• StringNullOrEmptyToInverseBoolValueConverter
• StringNullOrEmptyToVisibilityVisibleValueConverter
• StringNullOrEmptyToVisibilityCollapsedValueConverter
• ToLowerValueConverter
• ToUpperValueConverter

Performance Optimizations

Optimization	Benefit
BooleanBoxes	Zero-allocation boolean boxing
WeakAction	Memory leak prevention
WeakFunc<T>	Memory leak prevention with return values
PropertyDefaultValueConstants	Shared default values

Utilities

Utility	Purpose
DesignModeHelper	Detect design-time vs runtime
ValueConverterBase	Base class for custom converters
MultiValueConverterBase	Base class for multi-value converters
IErrorHandler	Centralized error handling

🌟 Why Choose Atc.XamlToolkit?

• ✅ Modern - Built for .NET 9 with latest C# features
• ✅ Cross-platform - Supports WPF, WinUI 3, and Avalonia
• ✅ High Performance - Optimized for minimal allocations
• ✅ Source Generators - Eliminate boilerplate code
• ✅ Well Documented - Comprehensive documentation and examples
• ✅ Battle Tested - Used in production applications
• ✅ Open Source - MIT licensed and community-driven

How to contribute

Contribution Guidelines

Coding Guidelines