OutWit.Common.MVVM.Avalonia.Generator 2.0.4

OutWit.Common.MVVM.Avalonia.Generator

Roslyn Source Generator for automatic Avalonia StyledProperty, DirectProperty, and AttachedProperty generation. This generator reads properties marked with the corresponding attributes and generates the necessary property fields and implementations at compile time.

?? Important: Don't Install Directly

This package should NOT be installed directly! It's automatically included when you install OutWit.Common.MVVM.Avalonia.

# ? Correct - Install the Avalonia package
dotnet add package OutWit.Common.MVVM.Avalonia

# ? Wrong - Don't install the generator directly
dotnet add package OutWit.Common.MVVM.Avalonia.Generator

What It Does

This source generator:

1. Finds Properties - Scans your code for properties marked with:

   • [StyledProperty] - generates Avalonia StyledProperty
   • [DirectProperty] - generates Avalonia DirectProperty with backing field
   • [AttachedProperty] - generates Avalonia AttachedProperty

2. Generates Code - Creates:

   • public static readonly StyledProperty<T> / DirectProperty<TOwner, T> / AttachedProperty<T> fields
   • Backing fields for DirectProperty
   • Get{PropertyName} and Set{PropertyName} methods for attached properties

3. Convention-Based Discovery - Automatically finds callback methods:

   • On{PropertyName}Changed for property changed handlers
   • {PropertyName}Coerce for coerce callbacks

How It Works

Input (Your Code)

using Avalonia.Controls;
using OutWit.Common.MVVM.Avalonia.Attributes;

namespace MyApp.Controls
{
    public partial class CustomButton : Button
    {
        [StyledProperty(DefaultValue = "Click Me")]
        public string Label { get; set; }

        [DirectProperty(DefaultValue = 0)]
        public int ClickCount { get; set; }

        // Convention: On{PropertyName}Changed
        private void OnLabelChanged(AvaloniaPropertyChangedEventArgs<string> e)
        {
            UpdateLabel();
        }
    }
}

Output (Generated Code)

// <auto-generated/>
#nullable enable

namespace MyApp.Controls
{
    partial class CustomButton
    {
        public static readonly StyledProperty<string> LabelProperty =
            AvaloniaProperty.Register<CustomButton, string>(nameof(Label), "Click Me");

        private int m_clickCount = 0;

        public static readonly DirectProperty<CustomButton, int> ClickCountProperty =
            AvaloniaProperty.RegisterDirect<CustomButton, int>(
                nameof(ClickCount), 
                o => o.m_clickCount, 
                (o, v) => o.m_clickCount = v,
                unsetValue: 0);
    }
}

Features

? Three Property Types

?? Convention-Based Callbacks

• Automatically finds On{PropertyName}Changed methods
• Automatically finds {PropertyName}Coerce methods

?? Attached Properties

public static partial class MyAttachedProperties
{
    [AttachedProperty(DefaultValue = false)]
    public static bool IsHighlighted { get; set; }
}

// Generates:
// - public static readonly AttachedProperty<bool> IsHighlightedProperty
// - public static bool GetIsHighlighted(AvaloniaObject obj)
// - public static void SetIsHighlighted(AvaloniaObject obj, bool value)

Requirements

• .NET SDK: 6.0 or later
• Target Framework: net6.0 or later
• Platform: Cross-platform (Avalonia)

Troubleshooting

Generated Code Not Appearing

1. Clean and rebuild: dotnet clean && dotnet build
2. Ensure class is marked as partial
3. Check using directive: using OutWit.Common.MVVM.Avalonia.Attributes;

View Generated Files

<PropertyGroup>
    <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
    <CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)Generated</CompilerGeneratedFilesOutputPath>
</PropertyGroup>

Related Packages

• OutWit.Common.MVVM.Avalonia - Main Avalonia package (install this!)
• OutWit.Common.MVVM - Cross-platform base classes

License

Licensed under the Apache License, Version 2.0. See LICENSE.

Attribution (optional)

If you use OutWit.Common.MVVM.Avalonia.Generator in a product, a mention is appreciated (but not required), for example: "Powered by OutWit.Common.MVVM.Avalonia.Generator (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.Avalonia.Generator");
• use the name to indicate compatibility (e.g., "OutWit.Common.MVVM.Avalonia.Generator-compatible").

You may not:

• use "OutWit.Common.MVVM.Avalonia.Generator" 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.Avalonia.Generator logo to promote forks or derived products without permission.

Remember: This package is automatically included with OutWit.Common.MVVM.Avalonia. Don't install it separately!