ButtonsViewModel.cs

using MaterialDesignColors.WpfExample.Domain;
using System;
using System.ComponentModel;
using System.Windows.Input;
using System.Windows.Threading;

namespace MaterialDesignColors.WpfExample
{
    public class ButtonsViewModel : INotifyPropertyChanged
    {
        private bool _showDismissButton;
        private double _dismissButtonProgress;
        private string _demoRestartCountdownText;
        private int _orClickMeCount;

        public ButtonsViewModel()
        {
            var autoStartingActionCountdownStart = DateTime.Now;
            var demoRestartCountdownComplete = DateTime.Now;
            var dismissRequested = false;
            DismissCommand = new AnotherCommandImplementation(_ => dismissRequested = true);
            ShowDismissButton = true;

            #region DISMISS button demo control
            //just some demo code for the DISMISS button...it's up to you to set 
            //up the progress on the button as it would be with a progress bar.
            //and then hide the button, do whatever action you want to do
            new DispatcherTimer(
                TimeSpan.FromMilliseconds(100), 
                DispatcherPriority.Normal, 
                new EventHandler((o, e) => 
                {
                    if (dismissRequested)
                    {
                        ShowDismissButton = false;
                        dismissRequested = false;
                        demoRestartCountdownComplete = DateTime.Now.AddSeconds(3);
                        DismissButtonProgress = 0;
                    }

                    if (ShowDismissButton)
                    {
                        var totalDuration = autoStartingActionCountdownStart.AddSeconds(5).Ticks - autoStartingActionCountdownStart.Ticks;
                        var currentDuration = DateTime.Now.Ticks - autoStartingActionCountdownStart.Ticks;
                        var autoCountdownPercentComplete = 100.0 / totalDuration * currentDuration;
                        DismissButtonProgress = autoCountdownPercentComplete;

                        if (DismissButtonProgress >= 100)
                        {
                            demoRestartCountdownComplete = DateTime.Now.AddSeconds(3);
                            ShowDismissButton = false;
                            UpdateDemoRestartCountdownText(demoRestartCountdownComplete, out _);
                        }
                    }
                    else
                    {
                        UpdateDemoRestartCountdownText(demoRestartCountdownComplete, out bool isComplete);
                        if (isComplete)
                        {
                            autoStartingActionCountdownStart = DateTime.Now;
                            ShowDismissButton = true;
                        }
                    }

                }), Dispatcher.CurrentDispatcher);
            #endregion

            IncrementOrClickMeCountCommand = new AnotherCommandImplementation(_ => OrClickMeCount += 1);
            OrClickMeCount = 0;

            //just some demo code for the SAVE button
            SaveCommand = new AnotherCommandImplementation(_ =>
            {
                if (IsSaveComplete == true)
                {
                    IsSaveComplete = false;
                    return;
                }

                if (SaveProgress != 0) return;

                var started = DateTime.Now;
                IsSaving = true;

                new DispatcherTimer(
                    TimeSpan.FromMilliseconds(50),
                    DispatcherPriority.Normal,
                    new EventHandler((o, e) =>
                    {
                        var totalDuration = started.AddSeconds(3).Ticks - started.Ticks;
                        var currentProgress = DateTime.Now.Ticks - started.Ticks;
                        var currentProgressPercent = 100.0 / totalDuration * currentProgress;

                        SaveProgress = currentProgressPercent;
                        
                        if (SaveProgress >= 100)
                        {
                            IsSaveComplete = true;
                            IsSaving = false;
                            SaveProgress = 0;
                            ((DispatcherTimer)o).Stop();
                        }

                    }), Dispatcher.CurrentDispatcher);
            });
        }

        #region Dismiss button demo

        public ICommand DismissCommand { get; }

        public bool ShowDismissButton
        {
            get { return _showDismissButton; }
            set { this.MutateVerbose(ref _showDismissButton, value, RaisePropertyChanged()); }
        }        

        public double DismissButtonProgress
        {
            get { return _dismissButtonProgress; }
            set { this.MutateVerbose(ref _dismissButtonProgress, value, RaisePropertyChanged()); }
        }

        public string DemoRestartCountdownText
        {
            get { return _demoRestartCountdownText; }
            private set { this.MutateVerbose(ref _demoRestartCountdownText, value, RaisePropertyChanged()); }
        }

        private void UpdateDemoRestartCountdownText(DateTime endTime, out bool isComplete)
        {
            var span = endTime - DateTime.Now;
            var seconds = Math.Round(span.TotalSeconds < 0 ? 0 : span.TotalSeconds);
            DemoRestartCountdownText = "Demo in " + seconds;
            isComplete = seconds == 0;
        }

        #endregion

        #region OrClickMe Demo
        public int OrClickMeCount
        {
            get { return _orClickMeCount; }
            private set { this.MutateVerbose(ref _orClickMeCount, value, RaisePropertyChanged()); }
        }
        public ICommand IncrementOrClickMeCountCommand { get; }

        #endregion

        #region floating Save button demo

        public ICommand SaveCommand { get; }

        private bool _isSaving;
        public bool IsSaving
        {
            get { return _isSaving; }
            private set { this.MutateVerbose(ref _isSaving, value, RaisePropertyChanged()); }
        }

        private bool _isSaveComplete;
        public bool IsSaveComplete
        {
            get { return _isSaveComplete; }
            private set { this.MutateVerbose(ref _isSaveComplete, value, RaisePropertyChanged()); }
        }

        private double _saveProgress;
        public double SaveProgress
        {
            get { return _saveProgress; }
            private set { this.MutateVerbose(ref _saveProgress, value, RaisePropertyChanged()); }
        }

        #endregion

        public event PropertyChangedEventHandler PropertyChanged;

        private Action<PropertyChangedEventArgs> RaisePropertyChanged()
        {
            return args => PropertyChanged?.Invoke(this, args);
        }
    }
}