我想，当我按下回车键，而不是在WPF MVVM应用程序中的Tab键移动到下一个控件。我怎样才能做到这一点？
如果你只想让几个文本框工作，Jay's answer是最好的。
如果你希望你的整个应用程序工作方式，makwana.a's answer是更好，但可以得到改善。
下面是我makwana.a's answer的修改，这是我在众多应用中都有使用。它还包括用于移动到下一个控制通过输入如果主动控制是一个复选框支持。除了使用标记属性决定的焦点是否应该动的，我用文本框的AcceptsReturn财产。我这样做是因为它默认为false，只会被设置为true多行文本框。在这种情况下，你不会想焦点移动到反正进入下一个控件。
在App.xaml中的OnStartup无效宣告这些事件处理程序
EventManager.RegisterClassHandler(typeof(TextBox), TextBox.KeyDownEvent, new KeyEventHandler(TextBox_KeyDown));
EventManager.RegisterClassHandler(typeof(CheckBox), CheckBox.KeyDownEvent, new KeyEventHandler(CheckBox_KeyDown));
下面是使它发挥广泛应用所需的其余方法进行。
void TextBox_KeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.Enter & (sender as TextBox).AcceptsReturn == false) MoveToNextUIElement(e);
}
void CheckBox_KeyDown(object sender, KeyEventArgs e)
{
MoveToNextUIElement(e);
//Sucessfully moved on and marked key as handled.
//Toggle check box since the key was handled and
//the checkbox will never receive it.
if (e.Handled == true)
{
CheckBox cb = (CheckBox)sender;
cb.IsChecked = !cb.IsChecked;
}
}
void MoveToNextUIElement(KeyEventArgs e)
{
// Creating a FocusNavigationDirection object and setting it to a
// local field that contains the direction selected.
FocusNavigationDirection focusDirection = FocusNavigationDirection.Next;
// MoveFocus takes a TraveralReqest as its argument.
TraversalRequest request = new TraversalRequest(focusDirection);
// Gets the element with keyboard focus.
UIElement elementWithFocus = Keyboard.FocusedElement as UIElement;
// Change keyboard focus.
if (elementWithFocus != null)
{
if (elementWithFocus.MoveFocus(request)) e.Handled = true;
}
}
编辑
我更新的代码，以纪念击键处理，如果运动是成功的，也切换复选框，因为钥匙被处理，将不再实现它。
下面是我用的只是这种附加属性。
首先，例如使用：
<TextBox Width="100"
Text="{Binding Name, Mode=TwoWay}"
UI:FocusAdvancement.AdvancesByEnterKey="True" />
（UI是，我已经定义了以下的命名空间的别名）。
附加属性：
public static class FocusAdvancement
{
public static bool GetAdvancesByEnterKey(DependencyObject obj)
{
return (bool)obj.GetValue(AdvancesByEnterKeyProperty);
}
public static void SetAdvancesByEnterKey(DependencyObject obj, bool value)
{
obj.SetValue(AdvancesByEnterKeyProperty, value);
}
public static readonly DependencyProperty AdvancesByEnterKeyProperty =
DependencyProperty.RegisterAttached("AdvancesByEnterKey", typeof(bool), typeof(FocusAdvancement),
new UIPropertyMetadata(OnAdvancesByEnterKeyPropertyChanged));
static void OnAdvancesByEnterKeyPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var element = d as UIElement;
if(element == null) return;
if ((bool)e.NewValue) element.KeyDown += Keydown;
else element.KeyDown -= Keydown;
}
static void Keydown(object sender, KeyEventArgs e)
{
if(!e.Key.Equals(Key.Enter)) return;
var element = sender as UIElement;
if(element != null) element.MoveFocus(new TraversalRequest(FocusNavigationDirection.Next));
}
}
你也说：“不是选项卡，”所以我不知道，如果你想抑制通常的方式使用标签的能力。我建议不要它，因为它是一种常见的，众所周知的模式，但如果是这样的话，你可以在附加属性添加PreviewKeyDown处理程序，检查Tab键，并设置为Handled = true事件参数。
样品溶液：在堆叠面板使用PreviewKeyDown。预览...是泡沫了，因此事件可以在更高层次上进行处理。您可能需要为不同的元素类型不同的方式处理这个，像按钮似乎应该保持回车键和回车键不改变焦点。
这里是XAML：
<StackPanel PreviewKeyDown="StackPanel_PreviewKeyDown" >
<TextBox >
Hello
</TextBox>
<TextBox>
World
</TextBox>
<TextBox>
test
</TextBox>
</StackPanel>
这里是后面的代码：
private void StackPanel_PreviewKeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.Enter)
{
TextBox s = e.Source as TextBox;
if (s != null)
{
s.MoveFocus(new TraversalRequest( FocusNavigationDirection.Next));
}
e.Handled = true;
}
}
这仅仅是概念证明一个沙箱。
快乐编码...
写这段代码在你的应用程序文件的onstartup事件
EventManager.RegisterClassHandler(GetType(TextBox), TextBox.KeyDownEvent, New RoutedEventHandler(AddressOf TextBox_KeyDown))
然后定义TextBox_KeyDown子作为
Private Sub TextBox_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Input.KeyEventArgs)
If e.Key = Key.Enter And TryCast(sender, TextBox).Tag <> "1" Then
' Creating a FocusNavigationDirection object and setting it to a
' local field that contains the direction selected.
Dim focusDirection As FocusNavigationDirection = FocusNavigationDirection.Next
' MoveFocus takes a TraveralReqest as its argument.
Dim request As New TraversalRequest(focusDirection)
' Gets the element with keyboard focus.
Dim elementWithFocus As UIElement = TryCast(Keyboard.FocusedElement, UIElement)
' Change keyboard focus.
If elementWithFocus IsNot Nothing Then
elementWithFocus.MoveFocus(request)
End If
End If
End Sub
我已经使用文本框的“标签”属性跳跃移动的焦点。即，如果一段时间后你不想要移动到上输入按键（在输入需要创建新的订单多行文本框的情况）下一个控件。只是标签属性设置为1。
希望这有助于：使用AttachedProperty http://madprops.org/blog/enter-to-tab-as-an-attached-property/
public class EnterKeyTraversal
{
public static bool GetIsEnabled(DependencyObject obj)
{
return (bool)obj.GetValue(IsEnabledProperty);
}
public static void SetIsEnabled(DependencyObject obj, bool value)
{
obj.SetValue(IsEnabledProperty, value);
}
static void ue_PreviewKeyDown(object sender, System.Windows.Input.KeyEventArgs e)
{
var ue = e.OriginalSource as FrameworkElement;
if (e.Key == Key.Enter)
{
e.Handled = true;
ue.MoveFocus(new TraversalRequest(FocusNavigationDirection.Next));
}
}
private static void ue_Unloaded(object sender, RoutedEventArgs e)
{
var ue = sender as FrameworkElement;
if (ue == null) return;
ue.Unloaded -= ue_Unloaded;
ue.PreviewKeyDown -= ue_PreviewKeyDown;
}
public static readonly DependencyProperty IsEnabledProperty =
DependencyProperty.RegisterAttached("IsEnabled", typeof(bool),
typeof(EnterKeyTraversal), new UIPropertyMetadata(false, IsEnabledChanged));
static void IsEnabledChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var ue = d as FrameworkElement;
if (ue == null) return;
if ((bool)e.NewValue)
{
ue.Unloaded += ue_Unloaded;
ue.PreviewKeyDown += ue_PreviewKeyDown;
}
else
{
ue.PreviewKeyDown -= ue_PreviewKeyDown;
}
}
}
<StackPanel my:EnterKeyTraversal.IsEnabled="True">
首先是发生于触发加时PreviewKeyDown触发，将调用每个元素。同时添加依赖属性并绑定FrameworkElement那你不会在把焦点。在触发提供Focus设置绑定元素。
我想出了下面的代码。需要注意的是它不设置e.Handled。此外，MoveFocus_Next不返回此举焦点是否成功，而是如果参数不为null。您可以添加或删除类型的控件需要处理。该代码的应用程序的主窗口是书面的，但处理其他窗口也。您还可以修改代码从App_Startup事件的调用。
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
public partial class MainWindow : Window
{
private bool MoveFocus_Next(UIElement uiElement)
{
if (uiElement != null)
{
uiElement.MoveFocus(new TraversalRequest(FocusNavigationDirection.Next));
return true;
}
return false;
}
public MainWindow()
{
InitializeComponent();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
EventManager.RegisterClassHandler(typeof(Window), Window.PreviewKeyUpEvent, new KeyEventHandler(Window_PreviewKeyUp));
}
private void Window_PreviewKeyUp(object sender, KeyEventArgs e)
{
if (e.Key == Key.Enter)
{
IInputElement inputElement = Keyboard.FocusedElement;
if (inputElement != null)
{
System.Windows.Controls.Primitives.TextBoxBase textBoxBase = inputElement as System.Windows.Controls.Primitives.TextBoxBase;
if (textBoxBase != null)
{
if (!textBoxBase.AcceptsReturn)
MoveFocus_Next(textBoxBase);
return;
}
if (
MoveFocus_Next(inputElement as ComboBox)
||
MoveFocus_Next(inputElement as Button)
||
MoveFocus_Next(inputElement as DatePicker)
||
MoveFocus_Next(inputElement as CheckBox)
||
MoveFocus_Next(inputElement as DataGrid)
||
MoveFocus_Next(inputElement as TabItem)
||
MoveFocus_Next(inputElement as RadioButton)
||
MoveFocus_Next(inputElement as ListBox)
||
MoveFocus_Next(inputElement as ListView)
||
MoveFocus_Next(inputElement as PasswordBox)
||
MoveFocus_Next(inputElement as Window)
||
MoveFocus_Next(inputElement as Page)
||
MoveFocus_Next(inputElement as Frame)
)
return;
}
}
}
}