WPF自定义控件:Collection类型的DependencyProperty

Question

我有一个CustomControl包含ListBox:

<UserControl x:Class="WpfApplication1.CustomList"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300">
    <Grid>
        <ListBox Name="listBox1" ItemsSource="{Binding ListSource}" />
    </Grid>
</UserControl>

我ItemsSource使用Code Behind中的属性绑定:

public partial class CustomList : UserControl, INotifyPropertyChanged
    {
        public CustomList( )
        {
            InitializeComponent( );
        }

        public ObservableCollection<object> ListSource
        {
            get
            {
                return (ObservableCollection<object>)GetValue( ListSourceProperty );
            }
            set
            {
                base.SetValue(CustomList.ListSourceProperty, value);
                NotifyPropertyChanged( "ListSource" );
            }
        }

        public static DependencyProperty ListSourceProperty = DependencyProperty.Register(
             "ListSource",
             typeof( ObservableCollection<object> ),
             typeof( CustomList ),
             new PropertyMetadata( OnValueChanged ) );

        private static void OnValueChanged( DependencyObject d, DependencyPropertyChangedEventArgs e )
        {
            ( (CustomList)d ).ListSource = (ObservableCollection<object>)e.NewValue;
        }

        public event PropertyChangedEventHandler PropertyChanged;
        public void NotifyPropertyChanged( string propertyName )
        {
            if(PropertyChanged != null)
            {
                PropertyChanged( this, new PropertyChangedEventArgs( propertyName ) );
            }
        }
    }

现在在我的MainWindow尝试ObservableCollection用我CustomControl和它的ListSource DependencyProperty 绑定一个"文章" :

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:local="clr-namespace:WpfApplication1"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        DataContext="{Binding RelativeSource={RelativeSource Self}}"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <local:CustomList ListSource="{Binding Articles}"/>
    </Grid>
</Window>

我得到的错误:

Error: 1 : Cannot create default converter to perform 'one-way' conversions between types 'System.Collections.ObjectModel.ObservableCollection`1[WpfApplication1.Article]' and 'System.Collections.ObjectModel.ObservableCollection`1[System.Object]'

如果在自定义控件中我有ObservableCollection<Article>而不是ObservableCollection<object>它的工作原理.那么有没有办法可以将自定义控件的DependencyProperty与对象的ObservableCollection绑定,而无需指定对象的类型？

Answer 1

将ListSource的类型更改为IEnumerable,然后您可以绑定到任何集合.