//******************************************************************************************************//  IViewModel.cs - Gbtc////  Copyright © 2012, Grid Protection Alliance.  All Rights Reserved.////  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See//  the NOTICE file distributed with this work for additional information regarding copyright ownership.//  The GPA licenses this file to you under the MIT License (MIT), the "License"; you may//  not use this file except in compliance with the License. You may obtain a copy of the License at:////      http://www.opensource.org/licenses/MIT////  Unless agreed to in writing, the subject software distributed under the License is distributed on an//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the//  License for the specific language governing permissions and limitations.////  Code Modification History://  ----------------------------------------------------------------------------------------------------//  03/31/2011 - Mehulbhai P Thakkar//       Generated original version of source code.//  05/25/2011 - J. Ritchie Carroll//       Added load/save/delete event operations to allow for user control interception.//  12/20/2012 - Starlynn Danyelle Gilliam//       Modified Header.////****************************************************************************************************** using System;using System.ComponentModel;using System.Windows.Input; namespace GSF.TimeSeries.UI{    /// <summary>    /// Represents an interface and common methods and properties each data model definition should use.    /// </summary>    public interface IViewModel : INotifyPropertyChanged    {        /// <summary>        /// Raised before record load is executed.        /// </summary>        event CancelEventHandler BeforeLoad;         /// <summary>        /// Raised when record has been loaded.        /// </summary>        event EventHandler Loaded;         /// <summary>        /// Raised before record save is executed.        /// </summary>        event CancelEventHandler BeforeSave;         /// <summary>        /// Raised when record has been saved.        /// </summary>        event EventHandler Saved;         /// <summary>        /// Raised before record delete is executed.        /// </summary>        event CancelEventHandler BeforeDelete;         /// <summary>        /// Raised when record has been deleted.        /// </summary>        event EventHandler Deleted;         /// <summary>        /// Gets <see cref="ICommand"/> object to perform Save operation.        /// </summary>        ICommand SaveCommand        {            get;        }         /// <summary>        /// Gets <see cref="ICommand"/> object to perform Delete operation.        /// </summary>        ICommand DeleteCommand        {            get;        }         /// <summary>        /// Gets <see cref="ICommand"/> object to perform Clear operation.        /// </summary>        ICommand ClearCommand        {            get;        }         /// <summary>        /// Gets boolean value to indicate if Save operation can be executed.        /// </summary>        /// <returns></returns>        bool CanSave        {            get;        }         /// <summary>        /// Gets boolean value to indicate if Delete operation can be executed.        /// </summary>        /// <returns></returns>        bool CanDelete        {            get;        }         /// <summary>        /// Gets boolean value to indicate if Clear operation can be executed.        /// </summary>        /// <returns></returns>        bool CanClear        {            get;        }         ///// <summary>        ///// Gets or sets error messages related to validation of property values.        ///// </summary>        ////string Error { get; set; }         /// <summary>        /// Method to save data into backend data store.        /// </summary>        void Save();         /// <summary>        /// Method to delete data from the backend data store.        /// </summary>        void Delete();         /// <summary>        /// Method to restore default values for data model object.        /// </summary>        void Clear();         /// <summary>        /// Method to retrieve collection of related objects.        /// </summary>        void Load();    }}