wpf - 绑定(bind)不提交？

Question

我有一个 TabControl绑定(bind)到 ICollectionView with 派生自 ObservableCollection<EditorTabViewModel> .我认为非常标准的 MVVM 多文档模式？无论如何，EditorTabViewModel有一个属性Content包含要显示的字符串。我发现绑定(bind)正在工作......

// Add 2 default tabs for a test, also set their Content property to the respective values ...
_tabs.Add(new EditorTabViewModel { Content = "Tab 1" });
_tabs.Add(new EditorTabViewModel { Content = "Tab 2" });

它的值被正确呈现

XAML

<!-- DataTemplate to render EditorTabViewModels -->
<DataTemplate DataType="{x:Type vm:EditorTabViewModel}">
    <me:MarkdownEditor 
        TextContent="{Binding Path=Content.Content, RelativeSource={RelativeSource Mode=TemplatedParent}, Mode=TwoWay}" 
        Options="{Binding Path=Options, RelativeSource={RelativeSource AncestorType={x:Type Window}}}" />
</DataTemplate>

结果

但是当我更改值、切换选项卡并返回时，我再次在构造函数中设置了字符串...如 this video (on screenr) 所示

Visual Studio Solution

Answer 1

在 MarkdownEditor.xaml 中将文本框“txtEditor”的 UpdateSourceTrigger 更改为 PropertyChanged。 TextBox 的默认 UpdateSourceTrigger 值为 LostFocus，更改选项卡时永远不会引发该事件。这就是为什么它恢复到以前的值

<TextBox Grid.Row="1" x:Name="txtEditor" AcceptsReturn="True"
         Text="{Binding TextContent, UpdateSourceTrigger=PropertyChanged}" 
         FontFamily="{Binding Path=Options.FontFamily}"
         FontSize="{Binding Path=Options.FontSize}"
         FontWeight="{Binding Path=Options.FontWeight}"
         Background="{Binding Path=Options.Background}"
         Foreground="{Binding Path=Options.Foreground}" />