/V1/trunk/Source/CAL/Composite.Wpf/Regions/ItemMetadata.cs

//===============================================================================

// Microsoft patterns & practices

// Composite Application Guidance for Windows Presentation Foundation

//===============================================================================

// Copyright (c) Microsoft Corporation.  All rights reserved.

// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY

// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT

// LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

// FITNESS FOR A PARTICULAR PURPOSE.

//===============================================================================

// The example companies, organizations, products, domain names,

// e-mail addresses, logos, people, places, and events depicted

// herein are fictitious.  No association with any real company,

// organization, product, domain name, email address, logo, person,

// places, or events is intended or should be inferred.

//===============================================================================



using System;

using System.Windows;



namespace Microsoft.Practices.Composite.Wpf.Regions

{

    /// <summary>

    /// Defines a class that wraps an item and adds metadata for it.

    /// </summary>

    public class ItemMetadata : DependencyObject

    {

        /// <summary>

        /// The name of the wrapped item.

        /// </summary>

        public static readonly DependencyProperty NameProperty =

            DependencyProperty.Register("Name", typeof(string), typeof(ItemMetadata));



        /// <summary>

        /// Value indicating whether the wrapped item is considered active.

        /// </summary>

        public static readonly DependencyProperty IsActiveProperty =

            DependencyProperty.Register("IsActive", typeof(bool), typeof(ItemMetadata), new PropertyMetadata(DependencyPropertyChanged));



        /// <summary>

        /// Initializes a new instance of <see cref="ItemMetadata"/>.

        /// </summary>

        /// <param name="item">The item to wrap.</param>

        public ItemMetadata(object item)

        {

            //check for null

            this.Item = item;

        }



        /// <summary>

        /// Gets the wrapped item.

        /// </summary>

        /// <value>The wrapped item.</value>

        public object Item { get; private set; }



        /// <summary>

        /// Gets or sets a name for the wrapped item.

        /// </summary>

        /// <value>The name of the wrapped item.</value>

        public string Name

        {

            get { return (string)GetValue(NameProperty); }

            set { SetValue(NameProperty, value); }

        }



        /// <summary>

        /// Gets or sets a value indicating whether the wrapped item is considered active.

        /// </summary>

        /// <value><see langword="true" /> if the item should be considered active; otherwise <see langword="false" />.</value>

        public bool IsActive

        {

            get { return (bool)GetValue(IsActiveProperty); }

            set { SetValue(IsActiveProperty, value); }

        }



        /// <summary>

        /// Occurs when metadata on the item changes.

        /// </summary>

        public event EventHandler MetadataChanged;



        /// <summary>

        /// Explicitly invokes <see cref="MetadataChanged"/> to notify listeners.

        /// </summary>

        public void InvokeMetadataChanged()

        {

            EventHandler metadataChangedHandler = MetadataChanged;

            if (metadataChangedHandler != null) metadataChangedHandler(this, EventArgs.Empty);

        }



        private static void DependencyPropertyChanged(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs args)

        {

            ItemMetadata itemMetadata = dependencyObject as ItemMetadata;

            if (itemMetadata != null)

            {

                itemMetadata.InvokeMetadataChanged();

            }

        }

    }

}