// MainPage.xaml.cs
using System.Collections.ObjectModel;
using Microsoft.Maui.Controls;

namespace TodoApp
{
    public partial class MainPage : ContentPage
    {
        ObservableCollection<string> todos = new ObservableCollection<string>();

        public MainPage()
        {
            InitializeComponent();
            TodoList.ItemsSource = todos;
        }

        void AddTodo_Clicked(object sender, EventArgs e)
        {
            if (!string.IsNullOrEmpty(TodoEntry.Text))
            {
                todos.Add(TodoEntry.Text);
                TodoEntry.Text = string.Empty;
            }
        }
    }
}

// MainPage.xaml
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="TodoApp.MainPage">
    <StackLayout Padding="20">
        <Entry x:Name="TodoEntry" Placeholder="New Todo" />
        <Button Text="Add" Clicked="AddTodo_Clicked" />
        <ListView x:Name="TodoList" />
    </StackLayout>
</ContentPage>

Demonstrates a simple Xamarin / .NET MAUI app with a Todo list, adding tasks via UI, and displaying them in a ListView.