Create MVVM Background Tasks with Progress Reporting

#region Copyright Notice

// Distributed under the Code Project Open License 
// ****************************************************
// 
// Copyright � 2011. David C. Veeneman
// All rights reserved 
// 
// Redistribution and use on source and binary forms, with or without modification 
// are permitted provided that the following conditions are met:
// 
// � Redistributions of source code must retain the above copyright notice, this 
// list of conditions and the following disclaimers. 
// 
// � Redistributions on binary form must reproduce the above copyright notice, this 
// list of conditions and the following disclaimer in the documentation anclior other 
// materials provided with the distribution. 
// 
// � Neither the name of David C. Veeneman nor Foresight Systems may be used to endorse 
// or promote products derived from this software without specific prior written permission. 
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER 'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, 
// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 
// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID C VEENEMAN OR FORERSIGHT SYSTEMS BE 
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSITTUIE GOODS OR SERVICES: LOSS OF USE, DATA OR PROFITS; OR 
// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
// LIABILITY, OR TORT. 

#endregion

using System;
using System.Windows;
using System.Windows.Controls;
using WpfProgressDemo.ViewModel;

namespace WpfProgressDemo.View.Services
{
    /// <summary>
    /// Provides services for the View.
    /// </summary>
    public static class ViewServices
    {
        #region Fields

        // Member variables
        private static ProgressDialog m_ProgressDialog;

        #endregion

        #region Service Methods

        /// <summary>
        /// Hides the Progress dialog.
        /// </summary>
        internal static void CloseProgressDialog()
        {
            m_ProgressDialog.Close();
        }

        /// <summary>
        /// Shows the Progress dialog.
        /// </summary>
        internal static void ShowProgressDialog(Window mainWindow, ProgressDialogViewModel viewModel)
        {
            m_ProgressDialog = new ProgressDialog();
            m_ProgressDialog.Owner = mainWindow;
            m_ProgressDialog.DataContext = viewModel;
            m_ProgressDialog.Show();
        }

        #endregion
    }
}