问棱镜:在一个区域中堆叠控件？

EN

Public Class StackPanelRegionAdapter
Inherits RegionAdapterBase(Of StackPanel)

    Public Sub New(ByVal behaviorFactory As IRegionBehaviorFactory)
        MyBase.New(behaviorFactory)
    End Sub

    Protected Overrides Sub Adapt(ByVal region As IRegion, ByVal regionTarget As StackPanel)
        AddHandler region.Views.CollectionChanged, Sub(sender As Object, e As NotifyCollectionChangedEventArgs)
            If e.Action = NotifyCollectionChangedAction.Add Then
                For Each element As FrameworkElement In e.NewItems
                    regionTarget.Children.Add(element)
                Next
            Else
            If e.Action = NotifyCollectionChangedAction.Remove Then
                For Each element In e.OldItems
                    If regionTarget.Children.Contains(element) Then
                        regionTarget.Children.Remove(element)
                    End If
                Next
            End If
        End Sub
    End Sub

    Protected Overrides Function CreateRegion() As Microsoft.Practices.Prism.Regions.IRegion
        Return New AllActiveRegion
    End Function
End Class

Protected Overrides Function ConfigureRegionAdapterMappings() As Microsoft.Practices.Prism.Regions.RegionAdapterMappings
    Dim mappings = MyBase.ConfigureRegionAdapterMappings()
    mappings.RegisterMapping(GetType(Grid), Container.Resolve(Of PrismExtensions.GridRegionAdapter))
    mappings.RegisterMapping(GetType(StackPanel), Container.Resolve(Of PrismExtensions.StackPanelRegionAdapter))
    Return mappings
End Function

using System.Collections.Specialized;
using System.Windows;
using System.Windows.Controls;
using Microsoft.Practices.Prism.Regions;

namespace FsNoteMaster3.Shell.Views.Utility
{
    /// <summary>
    /// Enables use of a StackPanel in a Prism region.
    /// </summary>
    /// <remarks> See stackoverflow.com/questions/4950464/prism-stacking-controls-in-a-region</remarks>
    public class StackPanelRegionAdapter : RegionAdapterBase<StackPanel>
    {
        /// <summary>
        /// Default constructor.
        /// </summary>
        /// <param name="behaviorFactory">Allows the registration of the default set of RegionBehaviors.</param>
        public StackPanelRegionAdapter(IRegionBehaviorFactory behaviorFactory) : base(behaviorFactory)
        {
        }

        /// <summary>
        /// Adapts a ContentControl to an IRegion. 
        /// </summary>
        /// <param name="region">The new region being used.</param>
        /// <param name="regionTarget">The object to adapt.</param>
        protected override void Adapt(IRegion region, StackPanel regionTarget)
        {
            region.Views.CollectionChanged += (sender, e) =>
            {
                switch (e.Action)
                {
                    case NotifyCollectionChangedAction.Add:
                        foreach (FrameworkElement element in e.NewItems) 
                        {
                            regionTarget.Children.Add(element);
                        }
                        break;

                    case NotifyCollectionChangedAction.Remove:
                        foreach (UIElement elementLoopVariable in e.OldItems) 
                        {
                            var element = elementLoopVariable;
                            if (regionTarget.Children.Contains(element)) 
                            {
                                regionTarget.Children.Remove(element);
                            }
                        }
                        break;
                }
            };
        }

        /// <summary>
        /// Template method to create a new instance of IRegion that will be used to adapt the object. 
        /// </summary>
        /// <returns>A new instance of IRegion.</returns>
        protected override Microsoft.Practices.Prism.Regions.IRegion CreateRegion()
        {
            return new AllActiveRegion();
        }
    }
}

/// <summary>
/// Configures the default region adapter mappings to use in the application.
/// </summary>
/// <returns>The RegionAdapterMappings instance containing all the mappings.</returns>
protected override RegionAdapterMappings ConfigureRegionAdapterMappings()
{
    var mappings = base.ConfigureRegionAdapterMappings();
    mappings.RegisterMapping(typeof(StackPanel), ServiceLocator.Current.GetInstance<StackPanelRegionAdapter>());
    return mappings;
}