我几天来一直在努力解决这个问题 - 谷歌没有任何帮助。
我有一个装有InkCanvas的RichTextBox。从InkCanvas收集并识别笔划。当装饰器关闭时，RichTextBox上的附加行为被明确用于强制焦点回到RichTextBox上。但是，据我所知，尽管明确要求关注RichTextBox，但RichTextBox永远不会收到信号。
发生了什么以及我该如何解决？
TIA
XAML
<ScrollViewer Grid.Row ="2" Grid.Column="1" VerticalScrollBarVisibility="Auto" >
<!--ScrollViewer can only have one child.-->
<Grid>
........................................
<!--
XAML that creates the adorned control and the adorner
-->
<ac:AdornedControl IsAdornerVisible="{Binding TranscriptionLayer.IsAdornerVisible}" Grid.ColumnSpan="2">
<!--#region Adorned Element-->
<!--
TranscriptionLayer will have an Adorner (inkcanvas) for handwriting recogntion.
The RichTextBox is the element being adorned and sets the size of the adornment object (i.e.,
the inkcanvas writing surface). The RichTextControl holds the actual transcript.
-->
<RichTextBox x:Name="RichTextControl" Panel.ZIndex="{Binding TranscriptionLayer.ZIndex}"
Height="{Binding VirtualPage.Height}"
Visibility="{Binding TranscriptionLayer.TranscriptIsVisible}"
SpellCheck.IsEnabled="True"
VerticalScrollBarVisibility="Auto"
AcceptsReturn="True" AcceptsTab="True"
>
<!--Remove blank line between paragraphs-->
<RichTextBox.Resources>
<Style TargetType="{x:Type Paragraph}">
<Setter Property="Margin" Value="0"/>
</Style>
</RichTextBox.Resources>
<i:Interaction.Behaviors>
<!--Update the menu and toolbar when a selection is made in the RichTextBox-->
<!--The behavior is bound to the SelectionChanged of the RichTextBox.
<b:RichTextBehavior AlignLeft ="{Binding TranscriptionLayer.AlignLeft}" /> -->
<b:RichTextBehavior
FontHeight="{Binding ElementName=Fontheight, Path=SelectedItem, Mode=TwoWay, Converter={c:NullToDoubleConverter}}"
TextFont="{Binding ElementName=Fonttype, Path=SelectedItem}"
TextBold="{Binding ElementName=ToggleBold, Path=IsChecked}"
Italic="{Binding ElementName=ToggleItalic, Path=IsChecked}"
Underline="{Binding ElementName=ToggleUnderline, Path=IsChecked}"
Strikethrough="{Binding ElementName=ToggleStrikethrough, Path=IsChecked}"
ParagraphTag ="{Binding ElementName=CurrentParagraph, Path=SelectedItem}"
SelectedText="{Binding TranscriptionLayer.SelectedText}"
IsFocused ="{Binding TranscriptionLayer.RichTextHasFocus}"
/>
</i:Interaction.Behaviors>
</RichTextBox>
<!--#endregion-->
<ac:AdornedControl.AdornerContent>
<!--#region The Adorner-->
<!-- This is the framework element as the adorner content. It is always on top of the adorned element. There adorned elements
is the RichTextConttrol.
The ItemsControl will expand to the width of the parent adorner which takes its size from the adorned element-the
RichTextConttrol. The ItemsControl inherits from System.Windows.FrameworkElement.
-->
<ItemsControl x:Name="WritingLayerControl" ItemsSource="{Binding TranscriptionLayer.WritingBoxes}" >
<!--
If the <ItemsControl.ItemsPanel> is not used, the ItemsControl will default to a vertical StackPanel.
-->
<ItemsControl.ItemTemplate>
<!--
DataTemplate and DataType point to a class, not a namespace!
-->
<DataTemplate DataType="{x:Type vm:WritingBoxViewModel}" >
<Grid>
<Grid.RowDefinitions>
<!-- 0 to be used for recogntion results-->
<RowDefinition Height="auto" />
<!-- 1 to be used for Ink -->
<RowDefinition Height="auto"/>
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Text="{Binding RecognitionResults}" Background="#100000FF"
Height="{Binding RecognitionResultsHeight}"/>
<!--
Binding Mode must be set to TwoWay on TheSelectedStrokes because by default binding works one way,
i.e. loading changes from the view model, but not updating the viewmodel back. So either use:
TheSelectedStrokes="{Binding SelectedStrokes, Mode=TwoWay}" or set it with
FrameworkPropertyMetadataOptions.BindsTwoWayByDefault in TheSelectedStrokes dependency definition.
Background is of type Brush, so must use ImageBrush, DrawingBrush, VisualBrush.
-->
<InkCanvas x:Name="InkCanvas" Grid.Row="1"
Height="{Binding WritingBoxHeight}" Strokes="{Binding Strokes}"
EditingMode="{Binding EditingMode}"
DefaultDrawingAttributes="{Binding DefaultDrawingAttributes}" >
<i:Interaction.Behaviors>
<b:InkCanvasBehavior DeletedStrokes="{Binding DrawingLayer.DeleteStrokes}" />
</i:Interaction.Behaviors>
<InkCanvas.Background>
<!--
Note: Making the DrawingBrush a StaticResource makes the XAML much more efficient as only one object
is created. It also is only created on the first pass and no update from the Bindings will happen so
the lines will not change even when the TypeSize is changed.
Viewport (type Rect) gives the position, width, and height of the base tile
-->
<DrawingBrush Stretch="Uniform" TileMode="Tile" Viewport="{Binding ViewPortBaseTile}" ViewportUnits="Absolute" >
<DrawingBrush.Drawing>
<GeometryDrawing>
<GeometryDrawing.Geometry>
<GeometryGroup>
<!--
X is horizontal displacement from origin.
Y is veritcal displacyement from origin.
Origin O(0,0) is top-left of InkCanvas.
-->
<!-- Vertical Line
<LineGeometry StartPoint="0,0" EndPoint="{Binding TileBottom}"/>
-->
<!-- Midline. Horizontal Line -->
<LineGeometry StartPoint="{Binding MidLineStartPoint}" EndPoint="{Binding MidLineEndPoint}"/>
<!-- BaseLine. Horizontal Line-->
<LineGeometry StartPoint="{Binding BaseLineStartPoint}" EndPoint="{Binding BaseLineEndPoint}"/>
</GeometryGroup>
</GeometryDrawing.Geometry>
<GeometryDrawing.Pen>
<Pen Thickness="1" Brush="Tomato"/>
</GeometryDrawing.Pen>
</GeometryDrawing>
</DrawingBrush.Drawing>
</DrawingBrush>
</InkCanvas.Background>
</InkCanvas>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<!--#endregion-->
</ac:AdornedControl.AdornerContent>
</ac:AdornedControl>
</Grid>
</ScrollViewer>
C＃
namespace Behaviors
{
public class RichTextBehavior : Behavior<RichTextBox>
{
protected override void OnAttached()
{
base.OnAttached();
AssociatedObject.SelectionChanged += RichTextBoxSelectionChanged;
AssociatedObject.TextChanged += RichTextBoxTextChanged;
}
protected override void OnDetaching()
{
base.OnDetaching();
AssociatedObject.SelectionChanged -= RichTextBoxSelectionChanged;
AssociatedObject.TextChanged -= RichTextBoxTextChanged;
}
....................................................
public static bool GetIsFocused(DependencyObject obj)
{
return (bool)obj.GetValue(IsFocusedProperty);
}
public static void SetIsFocused(DependencyObject obj, bool value)
{
obj.SetValue(IsFocusedProperty, value);
}
public static readonly DependencyProperty IsFocusedProperty =
DependencyProperty.RegisterAttached(
"IsFocused", typeof(bool), typeof(RichTextBehavior),
new UIPropertyMetadata(false, OnIsFocusedPropertyChanged));
private static void OnIsFocusedPropertyChanged(
DependencyObject d,
DependencyPropertyChangedEventArgs e)
{
var behavior = d as RichTextBehavior;
var uie = (UIElement)behavior.AssociatedObject;
if ((bool)e.NewValue)
{
uie.Focus(); // Don't care about false values.
}
}
最后一行，uie.Focus（）正确解析为RichTextBoxControl - 但未达到实际控件！
代码隐藏＆＃34; GotFocus（）＆＃34;事件永远不会被召唤：
代码隐藏
public partial class ProgressNotesView : UserControl
{
public ProgressNotesView()
{
InitializeComponent();
RichTextControl.GotFocus += RichTextControl_GotFocus;
RichTextControl.LostFocus += RichTextControl_LostFocus;
Loaded += (s, e) =>
{
// When used as a UserControl as Data first, the DataContext has already been set to the ViewModel
// before the UserControl is Initialized.
vm = (ProgressNoteViewModel)DataContext;
Fontheight.SelectedItem = 12.0;
};
}
private void RichTextControl_LostFocus(object sender, RoutedEventArgs e)
{
var y = 10;
}
private void RichTextControl_GotFocus(object sender, RoutedEventArgs e)
{
var x = 10;
}
那么当我在装饰器中使用InkCanvas时，需要将焦点返回到RichTextControl吗？
我真的非常感谢任何帮助（在我完全秃顶之前）！
TIA
答案 0 :(得分：0)
我尝试使用Snoop 2.8.0没有太多运气（我找不到焦点事件）。但是，放置
UIElement elementWithFocus = Keyboard.FocusedElement as UIElement;
在uie.Focus（）调用的各个点周围快速显示ScrollViewer正在接收Focus，而不是RichTextBox。进一步研究表明，在调用uie.Focus（）时，RichTextBox可见性已设置为隐藏。
确保在调用uie.Focus（）之前将RichTextBox可见性设置为Visible修复了所有问题。
获得的经验教训：显然，一个元素在获得焦点之前必须是可见的！