wpftoolkit/ExtendedWPFToolkitSolution/Src/Xceed.Wpf.AvalonDock/Controls/MenuItemEx.cs

/*************************************************************************************

   Extended WPF Toolkit

   Copyright (C) 2007-2013 Xceed Software Inc.

   This program is provided to you under the terms of the Microsoft Public
   License (Ms-PL) as published at http://wpftoolkit.codeplex.com/license 

   For more features, controls, and fast professional support,
   pick up the Plus Edition at http://xceed.com/wpf_toolkit

   Stay informed: follow @datagrid on Twitter or Like http://facebook.com/datagrids

  ***********************************************************************************/

using System.Windows.Controls;
using System.Windows;

namespace Xceed.Wpf.AvalonDock.Controls
{
  public class MenuItemEx : MenuItem
  {
    #region Members

    private bool _reentrantFlag = false;

    #endregion

    #region Constructors

    static MenuItemEx()
    {
      IconProperty.OverrideMetadata( typeof( MenuItemEx ), new FrameworkPropertyMetadata( new PropertyChangedCallback( OnIconPropertyChanged ) ) );
    }

    public MenuItemEx()
    {
    }

    #endregion

    #region Properties

    #region IconTemplate

    /// <summary>
    /// IconTemplate Dependency Property
    /// </summary>
    public static readonly DependencyProperty IconTemplateProperty = DependencyProperty.Register( "IconTemplate", typeof( DataTemplate ), typeof( MenuItemEx ),
            new FrameworkPropertyMetadata( ( DataTemplate )null, new PropertyChangedCallback( OnIconTemplateChanged ) ) );

    /// <summary>
    /// Gets or sets the IconTemplate property.  This dependency property 
    /// indicates the data template for the icon.
    /// </summary>
    public DataTemplate IconTemplate
    {
      get
      {
        return ( DataTemplate )GetValue( IconTemplateProperty );
      }
      set
      {
        SetValue( IconTemplateProperty, value );
      }
    }

    /// <summary>
    /// Handles changes to the IconTemplate property.
    /// </summary>
    private static void OnIconTemplateChanged( DependencyObject d, DependencyPropertyChangedEventArgs e )
    {
      ( ( MenuItemEx )d ).OnIconTemplateChanged( e );
    }

    /// <summary>
    /// Provides derived classes an opportunity to handle changes to the IconTemplate property.
    /// </summary>
    protected virtual void OnIconTemplateChanged( DependencyPropertyChangedEventArgs e )
    {
      UpdateIcon();
    }

    #endregion

    #region IconTemplateSelector

    /// <summary>
    /// IconTemplateSelector Dependency Property
    /// </summary>
    public static readonly DependencyProperty IconTemplateSelectorProperty = DependencyProperty.Register( "IconTemplateSelector", typeof( DataTemplateSelector ), typeof( MenuItemEx ),
            new FrameworkPropertyMetadata( ( DataTemplateSelector )null, new PropertyChangedCallback( OnIconTemplateSelectorChanged ) ) );

    /// <summary>
    /// Gets or sets the IconTemplateSelector property.  This dependency property 
    /// indicates the DataTemplateSelector for the Icon.
    /// </summary>
    public DataTemplateSelector IconTemplateSelector
    {
      get
      {
        return ( DataTemplateSelector )GetValue( IconTemplateSelectorProperty );
      }
      set
      {
        SetValue( IconTemplateSelectorProperty, value );
      }
    }

    /// <summary>
    /// Handles changes to the IconTemplateSelector property.
    /// </summary>
    private static void OnIconTemplateSelectorChanged( DependencyObject d, DependencyPropertyChangedEventArgs e )
    {
      ( ( MenuItemEx )d ).OnIconTemplateSelectorChanged( e );
    }

    /// <summary>
    /// Provides derived classes an opportunity to handle changes to the IconTemplateSelector property.
    /// </summary>
    protected virtual void OnIconTemplateSelectorChanged( DependencyPropertyChangedEventArgs e )
    {
      UpdateIcon();
    }

    #endregion

    #endregion

    #region Private Mehods

    private static void OnIconPropertyChanged( DependencyObject sender, DependencyPropertyChangedEventArgs e )
    {
      if( e.NewValue != null )
      {
        ( ( MenuItemEx )sender ).UpdateIcon();
      }
    }

    private void UpdateIcon()
    {
      if( _reentrantFlag )
        return;
      _reentrantFlag = true;
      if( IconTemplateSelector != null )
      {
        var dataTemplateToUse = IconTemplateSelector.SelectTemplate( Icon, this );
        if( dataTemplateToUse != null )
          Icon = dataTemplateToUse.LoadContent();
      }
      else if( IconTemplate != null )
        Icon = IconTemplate.LoadContent();
      _reentrantFlag = false;
    }

    #endregion
  }
}