移动焦点以响应XAML中的键盘事件

Question

我有一个带有两个文本框的WPF视图.当用户像Tab一样击中键盘上的向下箭头时,我想自动将焦点从第一个文本框向前移动到第二个文本框.

似乎我应该能够100%声明地执行此操作,但出于某种原因,我认为这样做的命令似乎没有做任何事情.这是我的第一次尝试不起作用:

<StackPanel>
    <TextBox Text="Test">
        <TextBox.InputBindings>
            <!-- I realize ComponentCommands.MoveFocusDown doesn't work...
                 This is just an example of what I've tried and the type
                 of answer I'm looking for -->
            <KeyBinding Key="Down" Command="ComponentCommands.MoveFocusDown" />
        </TextBox.InputBindings>
    </TextBox>
    <TextBox></TextBox>
</StackPanel>

有人对这个有经验么？好像我应该能够使用InputBindings或EventTrigger来做到这一点.

我正在使用MVVM,这是一个View问题.我可以放弃一点代码隐藏(作为一个视图关注,这是合理的),但它只是感觉我错过了一些东西.

Answer 1

我希望有人能提出更优雅的东西,但这就是我到目前为止所拥有的.它不是100%XAML,但它至少是通用的.

此示例显示了一个带有两个按钮和两个文本框的窗口.向下箭头在它们之间循环焦点.

我希望这有帮助.

<Window x:Class="WPF_Playground.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Window1" Height="300" Width="300"
    >
    <Window.CommandBindings>
        <CommandBinding Command="ComponentCommands.MoveFocusDown" Executed="CommandBinding_Executed"/>
    </Window.CommandBindings>
    <StackPanel KeyboardNavigation.DirectionalNavigation="Cycle">
        <Button>Tester</Button>
        <Button>Tester2</Button>
        <TextBox Text="Test">
            <TextBox.InputBindings>
                <KeyBinding Command="ComponentCommands.MoveFocusDown" Gesture="DOWN" />
            </TextBox.InputBindings>
        </TextBox>
        <TextBox Text="Test2">
            <TextBox.InputBindings>
                <KeyBinding Command="ComponentCommands.MoveFocusDown" Gesture="DOWN" />
            </TextBox.InputBindings>
        </TextBox>
    </StackPanel>
</Window>

事件处理程序(根本没有错误处理):

private void CommandBinding_Executed(object sender, ExecutedRoutedEventArgs e)
{
    UIElement senderElement = sender as UIElement;
    UIElement focusedElement = FocusManager.GetFocusedElement(senderElement) as UIElement;
    bool result = focusedElement.MoveFocus(new TraversalRequest(FocusNavigationDirection.Next));
    Debug.WriteLine(result);
}