How to implement Activity/Wait Indicator in dotnet Maui?

I needed to implement a wait indicator for a page in my Maui app.

Searching gave me this, but no step by step instructions.

So how do I do this?

Overview:

• The control to display the animation is called ActivityIndicator.
• ActivityIndicator is a visual element, should be part of your page.
  So, add an ActivityIndicator to your xaml.
• The state of the indicator is part of logic - should live in your view model.
  So, add a bindable property to your view model, and bind ActivityIndicator.IsRunning to this property.

Sample (I haven't tested, just for illustration)
Page (xaml):

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:customcontrols="clr-namespace:Waiter.Maui.CustomControls"
             x:Class="..." >

    <ContentPage.Content>
        <ActivityIndicator IsRunning="{Binding IsBusy}" />
        <Button Text="Go" Command="{Binding GoCommand}" />
    </ContentPage.Content>
</ContentPage>

ViewModel:

namespace MyNamespace
{
    public class MyViewModel : BaseViewModel
    {
        public MyViewModel()
        {
            GoCommand = new Command(execute: OnGo, canExecute: true);
        }

        public Command GoCommand { get; }
        private void OnGo()
        {
            MainThread.InvokeOnMainThreadAsync(async () =>
            {
                IsBusy = true;
                Thread.Sleep(5000);
                IsBusy = false;
                return result;
            });
        }
    }
}

BaseViewModel class (so that it can be re-used, from existing community content):

using System.ComponentModel;
using System.Runtime.CompilerServices;

namespace Waiter.Maui.Pages
{
    public class BaseViewModel : INotifyPropertyChanged
    {
        bool isBusy = false;
        public bool IsBusy
        {
            get { return isBusy; }
            set { SetProperty(ref isBusy, value); }
        }

        string title = string.Empty;
        public string Title
        {
            get { return title; }
            set { SetProperty(ref title, value); }
        }

        protected bool SetProperty<T>(ref T backingStore, T value,
            [CallerMemberName] string propertyName = "",
            Action onChanged = null)
        {
            if (EqualityComparer<T>.Default.Equals(backingStore, value))
                return false;

            backingStore = value;
            onChanged?.Invoke();
            OnPropertyChanged(propertyName);
            return true;
        }

        #region INotifyPropertyChanged
        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
        {
            var changed = PropertyChanged;
            if (changed == null)
                return;

            changed.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
        #endregion
    }
}