WPF：CellEditingTemplate如何通过双击或点击将焦点设置在内部控件上

Question

我用CellEditingTemplate编写了DataGrid的用户控件。此编辑模板的DataTemplate是一个文本框，并且光标将通过点击三次进入文本框，如果我想通过双击或一次单击将文本框上的光标设置为光标，我该怎么办？

这是我的代码：

<Window x:Class="MultiLineEditDataGrid.MainWindow" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:local="clr-namespace:MultiLineEditDataGrid" 
    Title="MainWindow" Height="350" Width="525"> 
<Grid DataContext="{Binding Source={x:Static Application.Current}, Path=CompanyManager}"> 
    <Grid.RowDefinitions> 
     <RowDefinition Height="270"/> 
     <RowDefinition Height="30"/> 
    </Grid.RowDefinitions> 
    <DataGrid ItemsSource="{Binding Companies}" CanUserAddRows="False" AutoGenerateColumns="False"> 
     <DataGrid.Resources> 
      <DataTemplate x:Key="cellTemplate"> 
       <TextBlock Text="{Binding Description}"/> 
      </DataTemplate> 
      <DataTemplate x:Key="cellEditingTemplate"> 
       <local:MultiLineTextBox Text="{Binding Description}"/> 
      </DataTemplate> 
     </DataGrid.Resources> 
     <DataGrid.Columns> 
      <DataGridTextColumn Header="Company" Binding="{Binding Name}"/> 
      <DataGridTemplateColumn Header="Description" 
            CellTemplate="{StaticResource cellTemplate}" 
            CellEditingTemplate="{StaticResource cellEditingTemplate}"/> 
     </DataGrid.Columns> 
    </DataGrid> 
    <Button Grid.Row="1" Content="Add" Command="{Binding AddCommand}"/> 
</Grid> 

MultiLineTextBox是i。从文本框继承文本框，并重写的onkeydown方法。

MultiLineTextBox代码：

public class MultiLineTextBox : TextBox 
{ 
    /// <summary> 
    /// On Key Down. 
    /// </summary> 
    /// <param name="e"></param> 
    protected override void OnKeyDown (KeyEventArgs e) 
    { 
     base.OnKeyDown (e); 
     string oldText = Text; 
     ModifierKeys keys = Keyboard.Modifiers; 
     if (e.Key == Key.Enter) 
     { 
      if ((Keyboard.Modifiers & ModifierKeys.Control).Equals (ModifierKeys.Control)) 
      { 
       int index = SelectionStart; 
       oldText = oldText.Insert (index, Environment.NewLine); 
       Text = oldText; 
       Select (index + 1, 0); 
       e.Handled = true; 
      } 
      else 
      { 
       e.Handled = false; 
      } 
     } 
     else if (e.Key == Key.Escape) 
     { 
      Text = oldText; 
      e.Handled = false; 
     } 
    } 
} 

Answer 1

我找到一个方法来解决这个问题，这里是我的代码。

<Window x:Class="MultiLineEditDataGrid.MainWindow" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:local="clr-namespace:MultiLineEditDataGrid" 
    Title="MainWindow" Height="350" Width="525"> 
<Grid DataContext="{Binding Source={x:Static Application.Current}, Path=CompanyManager}"> 
    <Grid.RowDefinitions> 
     <RowDefinition Height="270"/> 
     <RowDefinition Height="30"/> 
    </Grid.RowDefinitions> 
    <DataGrid ItemsSource="{Binding Companies}" CanUserAddRows="False" AutoGenerateColumns="False"> 
     <DataGrid.Resources> 
      <DataTemplate x:Key="cellTemplate"> 
       <TextBlock Text="{Binding Description}"/> 
      </DataTemplate> 
      <DataTemplate x:Key="cellEditingTemplate"> 
       <local:MultiLineTextBox x:Name="multiLineTxt" Text="{Binding Description}"/> 
       <DataTemplate.Triggers> 
        <Trigger SourceName="multiLineTxt" Property="IsVisible" Value="True"> 
         <Setter TargetName="multiLineTxt" Property="FocusManager.FocusedElement" Value="{Binding ElementName=multiLineTxt}"/> 
        </Trigger> 
       </DataTemplate.Triggers> 
      </DataTemplate> 
     </DataGrid.Resources> 
     <DataGrid.Columns> 
      <DataGridTextColumn Header="Company" Binding="{Binding Name}"/> 
      <DataGridTemplateColumn Header="Description" 
            CellTemplate="{StaticResource cellTemplate}" 
            CellEditingTemplate="{StaticResource cellEditingTemplate}"/> 
     </DataGrid.Columns> 
    </DataGrid> 
    <Button Grid.Row="1" Content="Add" Command="{Binding AddCommand}"/> 
</Grid> 

Answer 2

我不知道为什么，但以前的答案并没有我的情况下工作。我在这里找到了替代解决方案http://madcoderspeak.blogspot.ca/2010/04/set-keyboard-focus-when-user-begins.html

<DataGridTemplateColumn.CellEditingTemplate> 
    <DataTemplate> 
     <StackPanel> 
      <TextBox x:Name="editCommentTextBox" Text="{Binding Comment, Mode=TwoWay}" 
        FocusManager.FocusedElement="{Binding RelativeSource={RelativeSource Self}}"> 
      </TextBox> 
      <Label Content="{Binding Text, ElementName=editCommentTextBox, Converter={StaticResource CharCounterConverter}}"/> 
     </StackPanel> 
    </DataTemplate> 
</DataGridTemplateColumn.CellEditingTemplate>