avalonia-app-development

Avalonia App Development

Overview

Avalonia app entry: Program.cs builds and runs an AppBuilder. App.axaml + App.axaml.cs is the root. Platform lifetime determines how the app runs (Desktop vs Single-view for mobile/WASM).

Program.cs

using Avalonia;
using Avalonia.ReactiveUI; // or remove if not using ReactiveUI

class Program
{
    [STAThread]
    public static void Main(string[] args) => BuildAvaloniaApp()
        .StartWithClassicDesktopLifetime(args);

    public static AppBuilder BuildAvaloniaApp()
        => AppBuilder.Configure<App>()
            .UsePlatformDetect()
            .WithInterFont()
            .LogToTrace();
            // .UseReactiveUI() // add if using ReactiveUI
}

App.axaml

<Application xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             x:Class="MyApp.App"
             RequestedThemeVariant="Default">
    <Application.DataTemplates>
        <local:ViewLocator/>
    </Application.DataTemplates>
    <Application.Styles>
        <FluentTheme/>
    </Application.Styles>
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceInclude Source="avares://MyApp/Assets/Colors.axaml"/>
            </ResourceDictionary.MergedDictionaries>
            <SolidColorBrush x:Key="AccentBrush" Color="#FF5722"/>
        </ResourceDictionary>
    </Application.Resources>
</Application>

App.axaml.cs

public partial class App : Application
{
    public override void Initialize() => AvaloniaXamlLoader.Load(this);

    public override void OnFrameworkInitializationCompleted()
    {
        if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
        {
            desktop.MainWindow = new MainWindow
            {
                DataContext = new MainViewModel()
            };
        }
        else if (ApplicationLifetime is ISingleViewApplicationLifetime singleView)
        {
            singleView.MainView = new MainView
            {
                DataContext = new MainViewModel()
            };
        }
        base.OnFrameworkInitializationCompleted();
    }
}