如何使用MVVM手动增加/减少WPF进度条

<!-- View.xaml -->
<Window x:Class="WpfApp.View"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MVVM Progress Bar Example" Height="350" Width="500">
    <Grid>
        <ProgressBar Value="{Binding Progress}" Minimum="0" Maximum="100" Height="30" Width="300" VerticalAlignment="Center" HorizontalAlignment="Center"/>
        <Button Content="Increase" Command="{Binding IncreaseProgressCommand}" Height="30" Width="100" VerticalAlignment="Center" HorizontalAlignment="Left" Margin="50"/>
        <Button Content="Decrease" Command="{Binding DecreaseProgressCommand}" Height="30" Width="100" VerticalAlignment="Center" HorizontalAlignment="Right" Margin="50"/>
    </Grid>
</Window>

// ViewModel.cs
using System.ComponentModel;
using System.Windows.Input;

namespace WpfApp
{
    public class ViewModel : INotifyPropertyChanged
    {
        private int progress;

        public int Progress
        {
            get { return progress; }
            set
            {
                progress = value;
                OnPropertyChanged("Progress");
            }
        }

        public ICommand IncreaseProgressCommand { get; }
        public ICommand DecreaseProgressCommand { get; }

        public ViewModel()
        {
            IncreaseProgressCommand = new RelayCommand(IncreaseProgress);
            DecreaseProgressCommand = new RelayCommand(DecreaseProgress);
        }

        private void IncreaseProgress()
        {
            if (Progress < 100)
                Progress += 10;
        }

        private void DecreaseProgress()
        {
            if (Progress > 0)
                Progress -= 10;
        }

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void OnPropertyChanged(string propertyName)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

// RelayCommand.cs
using System;
using System.Windows.Input;

namespace WpfApp
{
    public class RelayCommand : ICommand
    {
        private readonly Action execute;
        private readonly Func<bool> canExecute;

        public RelayCommand(Action execute, Func<bool> canExecute = null)
        {
            this.execute = execute ?? throw new ArgumentNullException(nameof(execute));
            this.canExecute = canExecute;
        }

        public bool CanExecute(object parameter)
        {
            return canExecute == null || canExecute();
        }

        public void Execute(object parameter)
        {
            execute();
        }

        public event EventHandler CanExecuteChanged
        {
            add { CommandManager.RequerySuggested += value; }
            remove { CommandManager.RequerySuggested -= value; }
        }
    }
}