App.xaml.cs

#region Copyright

///////////////////////////////////////////////////////////////////////////////
//  File: App.cs
///////////////////////////////////////////////////////////////////////////////
//  Copyright (C) KGy SOFT, 2005-2024 - All Rights Reserved
//
//  You should have received a copy of the LICENSE file at the top-level
//  directory of this distribution.
//
//  Please refer to the LICENSE file if you want to use this source code.
///////////////////////////////////////////////////////////////////////////////

#endregion

#region Usings

using System;

using KGySoft.Drawing.Examples.WinUI.View;

using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Controls;
using Microsoft.UI.Xaml.Navigation;

using Windows.ApplicationModel;
using Windows.ApplicationModel.Activation;

#endregion

namespace KGySoft.Drawing.Examples.WinUI
{
    /// <summary>
    /// Provides application-specific behavior to supplement the default Application class.
    /// </summary>
    public partial class App : Application
    {
        #region Fields

        private Window? window;

        #endregion

        #region Constructors

        /// <summary>
        /// Initializes the singleton application object.  This is the first line of authored code
        /// executed, and as such is the logical equivalent of main() or WinMain().
        /// </summary>
        public App()
        {
            this.InitializeComponent();
        }

        #endregion

        #region Methods

        #region Protected Methods

        /// <summary>
        /// Invoked when the application is launched normally by the end user.  Other entry points
        /// will be used such as when the application is launched to open a specific file.
        /// </summary>
        /// <param name="e">Details about the launch request and process.</param>
        protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs e)
        {
            window = new Window { Title = "KGy SOFT Drawing WinUI Example App" };

            var rootFrame = window.Content as Frame;

            // Do not repeat app initialization when the Window already has content,
            // just ensure that the window is active
            if (rootFrame == null)
            {
                // Create a Frame to act as the navigation context and navigate to the first page
                rootFrame = new Frame();

                rootFrame.NavigationFailed += OnNavigationFailed;

                if (e.UWPLaunchActivatedEventArgs.PreviousExecutionState == ApplicationExecutionState.Terminated)
                {
                    //TODO: Load state from previously suspended application
                }

                // Place the frame in the current Window
                window.Content = rootFrame;
            }

            if (rootFrame.Content == null)
            {
                // When the navigation stack isn't restored navigate to the first page,
                // configuring the new page by passing required information as a navigation
                // parameter
                rootFrame.Navigate(typeof(MainPage), e.Arguments);
            }

            // Ensure the current window is active
            window.Activate();
        }

        #endregion

        #region Event handlers

        /// <summary>
        /// Invoked when Navigation to a certain page fails
        /// </summary>
        /// <param name="sender">The Frame which failed navigation</param>
        /// <param name="e">Details about the navigation failure</param>
        void OnNavigationFailed(object sender, NavigationFailedEventArgs e)
        {
            throw new Exception("Failed to load Page " + e.SourcePageType.FullName);
        }

        #endregion

        #endregion
    }
}