我有一个DataGrid绑定到名为MyObjects的ObservableCollection。 DataGrid有2列：一列是DataGridTextColumn，另一列是DataGridTemplateColumn。
我尝试实现的目标是，在选择单元格时按下键时，模板列的行为与文本列相似。
例如，当您从文本列中选择一个单元格并点击＆＃34; A＆＃34;键，单元格编辑模板激活和字母＆＃34; A＆＃34;输入到文本框中。
我想知道的是如何将此行为实现到模板列中（即，按键激活其单元编辑模板并将该字符传递给模板中的控件作为输入）。
我的搜索结果只能找到与编辑模板中的哪个控件在单元格之间进行标记时获得焦点的答案，这与我的问题不同。下面是我的DataGrid的XAML。
<DataGrid ItemsSource="{Binding MyObjects}" AutoGenerateColumns="False">
<DataGrid.Columns>
<DataGridTextColumn Header="Test" Binding="{Binding Test}"/>
<DataGridTemplateColumn Header="Date">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding Date}"/>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
<DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<!--This is the control that I want to focus!-->
<DatePicker SelectedDate="{Binding Date}"/>
</DataTemplate>
</DataGridTemplateColumn.CellEditingTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
编辑：
我编写了一个简单的帮助程序类，它允许在单元格模板加载时聚焦XAML指定的控件...结合Aled的答案，这非常接近我想要的！我只需要弄清楚如何将输入传递给聚焦控件...
问题是按键事件在控件加载事件之前被处理，所以我需要弄清楚如何将它们连接在一起......或者完全处理新方法。
public sealed class FrameworkElementFocusHelper
{
private static readonly DependencyProperty FocusOnLoadProperty =
DependencyProperty.RegisterAttached("FocusOnLoad",
typeof(bool),
typeof(FrameworkElementFocusHelper),
new UIPropertyMetadata(FocusOnLoadPropertyChanged));
public static void FocusOnLoadPropertyChanged(DependencyObject source, DependencyPropertyChangedEventArgs e)
{
FrameworkElement element = (FrameworkElement)source;
element.Loaded -= FrameworElementFocusHelperLoadedEvent;
if ((bool)e.NewValue == true)
element.Loaded += FrameworElementFocusHelperLoadedEvent;
}
public static void SetFocusOnLoad(DependencyObject element, bool value)
{
element.SetValue(FocusOnLoadProperty, value);
}
public static bool GetFocusOnLoad(DependencyObject element)
{
return (bool)element.GetValue(FocusOnLoadProperty);
}
public static void FrameworElementFocusHelperLoadedEvent(object sender, RoutedEventArgs e)
{
((FrameworkElement)sender).Focus();
}
}
用法：
<DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<DatePicker SelectedDate="{Binding Date}" rt:FrameworkElementFocusHelper.FocusOnLoad="true"/>
</DataTemplate>
</DataGridTemplateColumn.CellEditingTemplate>
答案 0 :(得分：4)
我有一种方法，至少让你在按键上进入编辑模式。
这里首先是一个扩展类，它提供了一些以编程方式获取行/列的方法（在这种情况下，并非所有这些都是必需的）：
namespace MyApp.Extensions
{
/// <summary>
/// Helper methods for the WPF DataGrid.
/// </summary>
public static class DataGridExtensions
{
/// <summary>
/// Gets a specific row from the data grid. If the DataGrid is virtualised the row will be scrolled into view.
/// </summary>
/// <param name="grid">The DataGrid.</param>
/// <param name="rowIndex">Row number to get.</param>
/// <returns></returns>
public static DataGridRow GetRow(this DataGrid grid, int rowIndex)
{
var row = (DataGridRow)grid.ItemContainerGenerator.ContainerFromIndex(rowIndex);
if (row == null)
{
grid.UpdateLayout();
grid.ScrollIntoView(grid.Items[rowIndex]);
row = (DataGridRow)grid.ItemContainerGenerator.ContainerFromIndex(rowIndex);
}
return row;
}
/// <summary>
/// Get the selected row.
/// </summary>
/// <param name="grid">DataGridRow.</param>
/// <returns>DataGridRow or null if no row selected.</returns>
public static DataGridRow GetSelectedRow(this DataGrid grid)
{
return (grid.SelectedIndex) < 0 ? null : (DataGridRow)grid.ItemContainerGenerator.ContainerFromIndex(grid.SelectedIndex);
}
/// <summary>
/// Gets a specific cell from the DataGrid.
/// </summary>
/// <param name="grid">The DataGrid.</param>
/// <param name="row">The row from which to get a cell from.</param>
/// <param name="column">The cell index.</param>
/// <returns>A DataGridCell.</returns>
public static DataGridCell GetCell(this DataGrid grid, DataGridRow row, int column)
{
if (row == null) return null;
var presenter = GetVisualChild<DataGridCellsPresenter>(row);
if (presenter == null)
{
// Virtualised - scroll into view.
grid.ScrollIntoView(row, grid.Columns[column]);
presenter = GetVisualChild<DataGridCellsPresenter>(row);
}
return (DataGridCell)presenter.ItemContainerGenerator.ContainerFromIndex(column);
}
/// <summary>
/// Gets a specific cell from the DataGrid.
/// </summary>
/// <param name="grid">The DataGrid.</param>
/// <param name="row">The row index.</param>
/// <param name="column">The cell index.</param>
/// <returns>A DataGridCell.</returns>
public static DataGridCell GetCell(this DataGrid grid, int row, int column)
{
var rowContainer = grid.GetRow(row);
return grid.GetCell(rowContainer, column);
}
/// <summary>
/// Gets the currently selected (focused) cell.
/// </summary>
/// <param name="grid">The DataGrid.</param>
/// <returns>DataGridCell or null if no cell is currently selected.</returns>
public static DataGridCell GetSelectedCell(this DataGrid grid)
{
var row = grid.GetSelectedRow();
if (row != null)
{
for (int i = 0; i < grid.Columns.Count; i++)
{
var cell = grid.GetCell(row, i);
if (cell.IsFocused)
return cell;
}
}
return null;
}
/// <summary>
/// Helper method to get a particular visual child.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="parent"></param>
/// <returns></returns>
private static T GetVisualChild<T>(Visual parent) where T : Visual
{
T child = default(T);
int numVisuals = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < numVisuals; i++)
{
var v = (Visual)VisualTreeHelper.GetChild(parent, i);
child = v as T ?? GetVisualChild<T>(v);
if (child != null)
{
break;
}
}
return child;
}
}
}
现在为Datagrid上的 PreviewKeyDown 事件添加处理程序。
<DataGrid ItemsSource="{Binding MyData}" PreviewKeyDown="MyDataGrid_OnPreviewKeyDown">
这是处理程序：
private void MyDataGrid_OnPreviewKeyDown(object sender, KeyEventArgs e)
{
var dg = sender as DataGrid;
// alter this condition for whatever valid keys you want - avoid arrows/tab, etc.
if (dg != null && !dg.IsReadOnly && e.Key == Key.Enter)
{
var cell = dg.GetSelectedCell();
if (cell != null && cell.Column is DataGridTemplateColumn)
{
cell.Focus();
dg.BeginEdit();
e.Handled = true;
}
}
}
有点faff，但似乎有效。将按键传递给编辑控件可能不太困难。
我确实通过创建自己的DataGridXYZColumn类来实现另一种方法，但是有一个主要的问题是，处理键盘输入的方法被标记为内部并且不可覆盖，所以我留下了这个方法！
答案 1 :(得分：0)
Aled Hughes's answer是一个很好的基础-在处理事件之前更改焦点的关键思想。但是，缺少一些关键点：
PreviewTextInput而不是PreviewKeyDown-输入的字符与按键并不1：1对应，此外，目前似乎无法在{{1 }}-它会吞下第一个字符以下处理程序应密切模仿PreviewKeyDown的行为，包括替代键码（例如alt + 6 + 4 = @），而忽略粘贴：
TextBox