logofclient/NamingWindow.axaml.cs

using System;
using System.Runtime.CompilerServices;
using System.Threading.Tasks;
using Avalonia.Controls;

namespace Logof_Client;

public partial class NamingWindow : Window
{
    public NamingWindow()
    {
        InitializeComponent();
    }

    public static Task<string> Show(Window parent, string input = "", string info = "Bitte geben Sie einen Namen ein:")
    {
        try
        {
            var wind = new NamingWindow
            {
                Title = "Name eingeben"
            };
            wind.FindControl<TextBlock>("Text").Text = info;
            var buttonPanel = wind.FindControl<StackPanel>("Buttons");
            var inputBox = wind.FindControl<TextBox>("Input");

            inputBox.Text = input;
            string res = null;

            void AddButton(string caption)
            {
                var btn = new Button { Content = caption };
                btn.Click += (_, __) =>
                {
                    res = inputBox.Text;
                    wind.Close();
                };
                buttonPanel.Children.Add(btn);
            }

            AddButton("Ok");


            var tcs = new TaskCompletionSource<string>();
            wind.Closed += delegate { tcs.TrySetResult(res); };
            if (parent != null)
                wind.ShowDialog(parent);
            else wind.Show();
            wind.Focus();

            return tcs.Task;
        }
        catch (Exception ex)
        {
            Console.WriteLine("Error while showing naming window: " + ex.Message);
            return Task.FromResult<string>(null!);
        }
    }
}