如何在UserControl上實現交互行爲

Question

我有以下具有附加行爲的UserControl。此刻，我必須選擇其中一個DataGrid項目才能運行該行爲。

只能在這裏猜測，但它是可以理解的，因爲這些容器不可聚焦或不應該註冊鍵盤事件，所以它會去下一個孩子？

我可以把這個功能放在窗口上，但是這個UserControl可以與另一個UserControl交換出去，我更喜歡它不會躺在身邊。 這只是我的應用程序中唯一的情況，窗口中唯一的東西是DataGrid，我不一定要選擇DataGrid項目來開始行爲。

我的問題是：是否有可能得到以下行爲工作？無論是在用戶控件，網格或可能允許這一點的其他控制。

<UserControl x:Class="UserManagement.LaunchPad" 
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
      xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
      xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
      xmlns:helpers="clr-namespace:UserManagement.Helpers" 
      xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity" 
      xmlns:sys="clr-namespace:System;assembly=mscorlib"> 

    <i:Interaction.Behaviors> 
     <helpers:OpenPopupBehaviors FindPopupObject="{Binding ElementName=PopupFind}" 
            GotoPopupObject="{Binding ElementName=PopupGoto}" /> 
    </i:Interaction.Behaviors> 

    <Grid> 
     <DockPanel> 
      <DataGrid /> 
     </DockPanel> 
     <Popup Name="PopupGoto" /> 
     <Popup Name="PopupFilter "/> 
    </Grid> 
</UserControl> 

這裏是行爲：

class OpenPopupBehaviors : Behavior<UserControl> 
{ 
    protected override void OnAttached() 
    { 
     base.OnAttached(); 
     this.AssociatedObject.KeyDown += _KeyBoardBehaviorKeyDown; 
    } 

    protected override void OnDetaching() 
    { 
     base.OnDetaching(); 
     this.AssociatedObject.KeyDown -= _KeyBoardBehaviorKeyDown; 
    } 

    void _KeyBoardBehaviorKeyDown(object sender, KeyEventArgs e) 
    { 
     if (e.Key == Key.F && (Keyboard.Modifiers & (ModifierKeys.Control)) == (ModifierKeys.Control)) 
     { 

      var popup = FindPopupObject as UserManagement.Controls.NonTopmostPopup; 
      if (popup == null) 
       return; 

      popup.IsOpen = true; 
     } 

     if (e.Key == Key.G && (Keyboard.Modifiers & (ModifierKeys.Control)) == (ModifierKeys.Control)) 
     { 
      var popup = GotoPopupObject as Popup; 
      if (popup == null) 
       return; 

      popup.IsOpen = true; 
     } 
    } 

    public static readonly DependencyProperty FindPopupObjectProperty = 
     DependencyProperty.RegisterAttached("FindPopupObject", typeof(object), typeof(OpenPopupBehaviors), new UIPropertyMetadata(null)); 

    public object FindPopupObject 
    { 
     get { return (object)GetValue(FindPopupObjectProperty); } 
     set { SetValue(FindPopupObjectProperty, value); } 
    } 

    public static readonly DependencyProperty GotoPopupObjectProperty = 
     DependencyProperty.RegisterAttached("GotoPopupObject", typeof(object), typeof(OpenPopupBehaviors), new UIPropertyMetadata(null)); 

    public object GotoPopupObject 
    { 
     get { return (object)GetValue(GotoPopupObjectProperty); } 
     set { SetValue(GotoPopupObjectProperty, value); } 
    } 
} 

Answer 1

到目前爲止，我可以看到的是，如果您的問題焦點

可以讓即使聚焦使用Preview事件接收的事件在控制的孩子或他們的後代

protected override void OnAttached() 
{ 
    base.OnAttached(); 
    this.AssociatedObject.PreviewKeyDown += _KeyBoardBehaviorKeyDown; 
} 

protected override void OnDetaching() 
{ 
    base.OnDetaching(); 
    this.AssociatedObject.PreviewKeyDown-= _KeyBoardBehaviorKeyDown; 
} 

我改變了KeyDown至PreviewKeyDown

只要AssociatedObject重點關注它或其中的任何小孩，上述解決方案將工作。如果您期待全局控制，那麼您可能需要將事件附加到頂層元素，例如。 Window

所以爲了做到這一點，您需要找到AssociatedObject的相應父項並將事件附加到相同的父項。

也確保以下轉換是有效

FindPopupObject as UserManagement.Controls.NonTopmostPopup; 

它可能是

FindPopupObject as Popup;