Question

我一直在讨论这个问题，在WindowForms中做起来很简单。

我正在制作一个IRC客户端，每个频道的连接都会有一个选项卡。每个选项卡都需要显示许多内容，UserList，MessageHistory，Topic。

在WindowForms中，我只是从TabItem继承，添加了一些自定义属性和控件，并完成了。

在WPF中，我在解决如何操作方面遇到了一些小问题。

我尝试了很多方法，下面是我当前的方法，但我无法将TextBox绑定到Topic属性。

    <Style TargetType="{x:Type t:IRCTabItem}" BasedOn="{StaticResource {x:Type TabItem}}" >
    <Setter Property="ContentTemplate">
        <Setter.Value>
            <DataTemplate>
                <Grid>
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width="540" />
                        <ColumnDefinition />
                    </Grid.ColumnDefinitions>
                    <StackPanel Grid.Column="0">
                        <TextBox Text="{Binding Topic, RelativeSource={RelativeSource AncestorType={x:Type t:IRCTabItem}}}" />   
                    </StackPanel>
                </Grid>
            </DataTemplate>              
        </Setter.Value>
    </Setter>
</Style>

和Codebehind

 public class IRCTabItem : TabItem
    {
        static IRCTabItem()
        {
            //This OverrideMetadata call tells the system that this element wants to provide a style that is different than its base class.
            //This style is defined in themes\generic.xaml
            //DefaultStyleKeyProperty.OverrideMetadata(typeof(IRCTabItem),
             //   new FrameworkPropertyMetadata(typeof(IRCTabItem)));
        }

        public static readonly RoutedEvent CloseTabEvent =
            EventManager.RegisterRoutedEvent("CloseTab", RoutingStrategy.Bubble,
                typeof(RoutedEventHandler), typeof(IRCTabItem));

        public event RoutedEventHandler CloseTab
        {
            add { AddHandler(CloseTabEvent, value); }
            remove { RemoveHandler(CloseTabEvent, value); }
        }

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();

            Button closeButton = base.GetTemplateChild("PART_Close") as Button;
            if (closeButton != null)
                closeButton.Click += new System.Windows.RoutedEventHandler(closeButton_Click);
        }

        void closeButton_Click(object sender, System.Windows.RoutedEventArgs e)
        {
            this.RaiseEvent(new RoutedEventArgs(CloseTabEvent, this));
        }

        public bool Closeable
        {
            get { return (bool)GetValue(CloseableProperty); }
            set { SetValue(CloseableProperty, value); }
        }
        public static readonly DependencyProperty CloseableProperty = DependencyProperty.Register("Closeable", typeof(bool), typeof(IRCTabItem), new FrameworkPropertyMetadata(true, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));


        public List<String> UserList
        {
            get { return (List<string>)GetValue(UserListProperty); }
            set { SetValue(UserListProperty, value); }
        }
        public static readonly DependencyProperty UserListProperty = DependencyProperty.Register("UserList", typeof(List<String>), typeof(IRCTabItem), new FrameworkPropertyMetadata(new List<String>(), FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

        public String Topic
        {
            get { return (string)GetValue(TopicProperty); }
            set { SetValue(TopicProperty, value); }
        }
        public static readonly DependencyProperty TopicProperty = DependencyProperty.Register("Topic", typeof(String), typeof(IRCTabItem), new FrameworkPropertyMetadata("Not Connected", FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

        public bool HasAlerts
        {
            get { return (bool)GetValue(HasAlertsProperty); }
            set { SetValue(HasAlertsProperty, value); }
        }
        public static readonly DependencyProperty HasAlertsProperty = DependencyProperty.Register("HasAlerts", typeof(bool), typeof(IRCTabItem), new FrameworkPropertyMetadata(false, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));


    }

所以我的问题是：

我是以正确的方式（最佳做法）吗？如果是这样，我如何将DataTemplate绑定到Properties？如果不是这样，那么实现我想要实现的目标的正确方法是什么？

编辑1：添加了Peter Stephens的建议编辑2：添加了可见编辑摘要编辑3：标签

Answer 1

您遇到的一个问题是您的依赖项属性实现不正确。

主题应该像这样实现：

public String Topic 
{ 
    get { return (string) GetValue(TopicProperty); }
    set { SetValue(TopicProperty, value); }
}
public static readonly DependencyProperty TopicProperty = 
    DependencyProperty.Register("Topic", typeof(String), 
        typeof(IRCTabItem), new FrameworkPropertyMetadata("Not Connected", 
        FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

您需要将CLR属性视为围绕WPF依赖项属性的语法糖。让WPF属性处理值的存储，否则您将有效地拥有两个具有两个不同值的属性。

Answer 2

我相信您的绑定表达式缺少相对来源的模式。

试试这个：

<TextBox Text="{Binding Topic, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type t:IRCTabItem}}}" />

Mode的默认值为null，所以如果你不包含那个设置，事情可能就不会那么好了。

WPF TabItem自定义ContentTemplate

2 个答案: