在键绑定用户控件，当文本框具有焦点不起作用(KeyBinding in UserControl do

下面的情况。我有一个用户控件有五个键绑定。当文本框具有焦点的用户控件的按键绑定停止射击..

有没有办法来解决这个“问题”？

<UserControl.InputBindings>
    <KeyBinding Key="PageDown" Modifiers="Control" Command="{Binding NextCommand}"></KeyBinding>
    <KeyBinding Key="PageUp" Modifiers="Control" Command="{Binding PreviousCommand}"></KeyBinding>
    <KeyBinding Key="End" Modifiers="Control"  Command="{Binding LastCommand}"></KeyBinding>
    <KeyBinding Key="Home" Modifiers="Control" Command="{Binding FirstCommand}"></KeyBinding>
    <KeyBinding Key="F" Modifiers="Control" Command="{Binding SetFocusCommand}"></KeyBinding>
</UserControl.InputBindings>
<TextBox Text="{Binding FilterText, UpdateSourceTrigger=PropertyChanged}">
    <TextBox.InputBindings>
        <KeyBinding Gesture="Enter" Command="{Binding RelativeSource={RelativeSource AncestorType={x:Type UserControl }}, Path=DataContext.FilterCommand}"></KeyBinding>
    </TextBox.InputBindings>
</TextBox>

这似乎功能键（F1等）和ALT + [关键]做的工作。我相信CTRL和SHIFT修饰在某种程度上向上冒泡到用户控件的“堵”的事件。

Answer 1:

之所以一些输入绑定工作，和一些不就是TextBox控件捕获并处理一些键绑定。例如，它可以处理CTRL + V进行粘贴，CTRL + 主页要去文本等，如Ctrl + F3，另一方面其他键组合不被处理的文本框的开始，所以他们会泡起来。

如果你只是想禁用文本框的输入绑定，这将是简单的-你可以使用ApplicationCommands.NotACommand命令，这将禁用默认行为。例如，在下面的情况下，粘贴与CTRL + V将被禁用：

<TextBox>
    <TextBox.InputBindings>
        <KeyBinding Key="V" Modifiers="Control" Command="ApplicationCommands.NotACommand" />
    </TextBox.InputBindings>
</TextBox>

然而，使其冒泡给用户控制是有点麻烦。我的建议是创建一个将被应用到该用户控件附加的行为，登记其PreviewKeyDown事件，他们到达之前文本框在必要时执行其输入绑定。这将输入绑定执行时的用户控件给予优先。

我写了实现这一功能，让你开始一个基本的行为：

public class InputBindingsBehavior
{
    public static readonly DependencyProperty TakesInputBindingPrecedenceProperty =
        DependencyProperty.RegisterAttached("TakesInputBindingPrecedence", typeof(bool), typeof(InputBindingsBehavior), new UIPropertyMetadata(false, OnTakesInputBindingPrecedenceChanged));

    public static bool GetTakesInputBindingPrecedence(UIElement obj)
    {
        return (bool)obj.GetValue(TakesInputBindingPrecedenceProperty);
    }

    public static void SetTakesInputBindingPrecedence(UIElement obj, bool value)
    {
        obj.SetValue(TakesInputBindingPrecedenceProperty, value);
    }

    private static void OnTakesInputBindingPrecedenceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        ((UIElement)d).PreviewKeyDown += new KeyEventHandler(InputBindingsBehavior_PreviewKeyDown);
    }

    private static void InputBindingsBehavior_PreviewKeyDown(object sender, KeyEventArgs e)
    {
        var uielement = (UIElement)sender;

        var foundBinding = uielement.InputBindings
            .OfType<KeyBinding>()
            .FirstOrDefault(kb => kb.Key == e.Key && kb.Modifiers == e.KeyboardDevice.Modifiers);

        if (foundBinding != null)
        {
            e.Handled = true;
            if (foundBinding.Command.CanExecute(foundBinding.CommandParameter))
            {
                foundBinding.Command.Execute(foundBinding.CommandParameter);
            }
        }
    }
}

用法：

<UserControl local:InputBindingsBehavior.TakesInputBindingPrecedence="True">
    <UserControl.InputBindings>
        <KeyBinding Key="Home" Modifiers="Control" Command="{Binding MyCommand}" />
    </UserControl.InputBindings>
    <TextBox ... />
</UserControl>

希望这可以帮助。

Answer 2:

阿迪·莱斯特的解决方案效果很好。下面是使用行为类似的解决方案。 C＃代码：

public class AcceptKeyBinding : Behavior<UIElement>
{


    private TextBox _textBox;



    /// <summary>
    ///  Subscribes to the PreviewKeyDown event of the <see cref="TextBox"/>.
    /// </summary>
    protected override void OnAttached()
    {
        base.OnAttached();

        _textBox = AssociatedObject as TextBox;

        if (_textBox == null)
        {
            return;
        }

        _textBox.PreviewKeyDown += TextBoxOnPreviewKeyDown;
    }

    private void TextBoxOnPreviewKeyDown(object sender, KeyEventArgs keyEventArgs)
    {
        var uielement = (UIElement)sender;

        var foundBinding = uielement.InputBindings
            .OfType<KeyBinding>()
            .FirstOrDefault(kb => kb.Key == keyEventArgs.Key && kb.Modifiers ==           keyEventArgs.KeyboardDevice.Modifiers);

        if (foundBinding != null)
        {
            keyEventArgs.Handled = true;
            if (foundBinding.Command.CanExecute(foundBinding.CommandParameter))
            {
                foundBinding.Command.Execute(foundBinding.CommandParameter);
            }
        }
    }

    /// <summary>
    ///     Unsubscribes to the PreviewKeyDown event of the <see cref="TextBox"/>.
    /// </summary>
    protected override void OnDetaching()
    {
        if (_textBox == null)
        {
            return;
        }

        _textBox.PreviewKeyDown -= TextBoxOnPreviewKeyDown;

        base.OnDetaching();
    }

}

而XAML：

<TextBox>
  <TextBox.InputBindings>
      <KeyBinding Key="Enter" Modifiers="Shift" Command="{Binding CommandManager[ExecuteCommand]}"
          CommandParameter="{Binding ExecuteText}" />
  </TextBox.InputBindings>
      <i:Interaction.Behaviors>
         <behaviours:AcceptKeyBinding />
      </i:Interaction.Behaviors>
</TextBox>

Answer 3:

除了阿迪莱斯特他（非常有用）的答案，我想提出一些改进/扩展，帮助我与我的实现。

Gesture.Matches

该foundBinding也可以通过调用Gesture.Matches完成。更改foundBinding Linq查询到以下几点：

KeyBinding foundBinding = ((UIElement)this).InputBindings
            .OfType<KeyBinding>()
            .FirstOrDefault(inputBinding => inputBinding.Gesture.Matches(sender, eventArgs));

MouseBinding

此外，你还可以定义MouseBindings。

<MouseBinding Command="{Binding DataContext.AddInputValueCommand, ElementName=root}" CommandParameter="{Binding}" Gesture="Shift+MiddleClick" />

然后，您还需要订阅PreviewMouseEvents如PreviewMouseUp和PreviewMouseDoubleClick。实现是那么几乎一样的键绑定。

private void OnTextBoxPreviewMouseUp(object sender, MouseButtonEventArgs eventArgs)
{
    MouseBinding foundBinding = ((UIElement)this).InputBindings
        .OfType<MouseBinding>()
        .FirstOrDefault(inputBinding => inputBinding.Gesture.Matches(sender, eventArgs));

    if (foundBinding != null)
    {
        eventArgs.Handled = true;
        if (foundBinding.Command.CanExecute(foundBinding.CommandParameter))
        {
            foundBinding.Command.Execute(foundBinding.CommandParameter);
        }
    }
}

Answer 4:

<UserControl.Style>
    <Style TargetType="UserControl">
        <Style.Triggers>
            <Trigger Property="IsKeyboardFocusWithin" Value="True">
                <Setter Property="FocusManager.FocusedElement" Value="   {Binding ElementName=keyPressPlaceHoler}" />
                </Trigger>
        </Style.Triggers>
    </Style>
</UserControl.Style>

keyPressPlaceHoler是你的目标的容器的名称uielement

记得设置Focusable="True"的用户控件

文章来源: KeyBinding in UserControl doesn't work when TextBox has the focus