我的数据网格有一些问题。我的项目正在将一个 Delphi 项目转换为 .Net。产品所有者希望数据网格具有相同的行为。
当定位在最后一个单元格上并按下 tab 或 enter 时，应该会发生以下情况：
- 添加了一个新行
- 新行中的第一个单元格被选中
对数据网格的其他要求是：
- 一旦获得焦点，焦点应保留在数据网格内（ALT + 组合键是再次离开数据网格的方式）。
- 数据网格是数据绑定的
- 数据网格用于 MVVM
- 我们使用 .net4.0 完整配置文件
问问题
2869 次
2 回答
2
This article had the best solution I could find.
I preferred to use an attached property rather than a behavior, since this enabled me to set it easily in the default style for DataGrid. Here's the code:
namespace SampleDataGridApp
{
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
/// <summary>
/// An attached behavior that modifies the tab behavior for a <see cref="DataGrid"/>.
/// </summary>
public static class DataGridBehavior
{
/// <summary>
/// Identifies the <c>NewLineOnTab</c> attached property.
/// </summary>
public static readonly DependencyProperty NewLineOnTabProperty = DependencyProperty.RegisterAttached(
"NewLineOnTab",
typeof(bool),
typeof(DataGridBehavior),
new PropertyMetadata(default(bool), OnNewLineOnTabChanged));
/// <summary>
/// Sets the value of the <c>NewLineOnTab</c> attached property.
/// </summary>
/// <param name="element">The <see cref="DataGrid"/>.</param>
/// <param name="value">A value indicating whether to apply the behavior.</param>
public static void SetNewLineOnTab(DataGrid element, bool value)
{
element.SetValue(NewLineOnTabProperty, value);
}
/// <summary>
/// Gets the value of the <c>NewLineOnTab</c> attached property.
/// </summary>
/// <param name="element">The <see cref="DataGrid"/>.</param>
/// <returns>A value indicating whether to apply the behavior.</returns>
public static bool GetNewLineOnTab(DataGrid element)
{
return (bool)element.GetValue(NewLineOnTabProperty);
}
/// <summary>
/// Called when the value of the <c>NewLineOnTab</c> property changes.
/// </summary>
/// <param name="sender">The event sender.</param>
/// <param name="e">The event arguments.</param>
private static void OnNewLineOnTabChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
DataGrid d = sender as DataGrid;
if (d == null)
{
return;
}
bool newValue = (bool)e.NewValue;
bool oldValue = (bool)e.OldValue;
if (oldValue == newValue)
{
return;
}
if (oldValue)
{
d.PreviewKeyDown -= AssociatedObjectKeyDown;
}
else
{
d.PreviewKeyDown += AssociatedObjectKeyDown;
KeyboardNavigation.SetTabNavigation(d, KeyboardNavigationMode.Contained);
}
}
/// <summary>
/// Handles the <see cref="UIElement.KeyDown"/> event for a <see cref="DataGridCell"/>.
/// </summary>
/// <param name="sender">The event sender.</param>
/// <param name="e">The event arguments.</param>
private static void AssociatedObjectKeyDown(object sender, KeyEventArgs e)
{
if (e.Key != Key.Tab)
{
return;
}
DataGrid dg = e.Source as DataGrid;
if (dg == null)
{
return;
}
if (dg.CurrentColumn.DisplayIndex == dg.Columns.Count - 1)
{
var icg = dg.ItemContainerGenerator;
if (dg.SelectedIndex == icg.Items.Count - 2)
{
dg.CommitEdit(DataGridEditingUnit.Row, false);
}
}
}
}
}
My default style looks like this:
<Style TargetType="DataGrid">
<Setter Property="GridLinesVisibility" Value="None" />
<Setter Property="KeyboardNavigation.TabNavigation" Value="Contained" />
<Setter Property="sampleDataGridApp:DataGridBehavior.NewLineOnTab" Value="True" />
<Setter Property="IsSynchronizedWithCurrentItem" Value="True" />
</Style>
If the last column's DataGridCell has it's IsTabStop set to false like in this example the above will not work.
Here is a buggy workaround:
private static void AssociatedObjectKeyDown(object sender, KeyEventArgs e)
{
if (e.Key != Key.Tab)
{
return;
}
DataGrid dg = e.Source as DataGrid;
if (dg == null)
{
return;
}
int offSet = 1;
var columnsReversed = dg.Columns.Reverse();
foreach (var dataGridColumn in columnsReversed)
{
// Bug: This makes the grand assumption that a readonly column's "DataGridCell" has IsTabStop == false;
if (dataGridColumn.IsReadOnly)
{
offSet++;
}
else
{
break;
}
}
if (dg.CurrentColumn.DisplayIndex == (dg.Columns.Count - offSet))
{
var icg = dg.ItemContainerGenerator;
if (dg.SelectedIndex == icg.Items.Count - 2)
{
dg.CommitEdit(DataGridEditingUnit.Row, false);
}
}
}
于 2013-11-07T21:40:14.520 回答
0
好的，我已经为这个问题奋斗了好几个小时了。我已经尝试了几乎所有提出的解决方案，这就是我发现的适合我的解决方案......
private void grid_PreviewKeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.Tab)
{
if (grid.SelectedIndex == grid.Items.Count - 2 && grid.CurrentColumn.DisplayIndex == grid.Columns.Count - 1)
{
grid.CommitEdit(DataGridEditingUnit.Row, false);
e.Handled = true;
}
}
}
private void DataGrid_RowEditEnding(object sender, DataGridRowEditEndingEventArgs e)
{
if (grid.SelectedIndex == grid.Items.Count - 2)
{
grid.SelectedIndex = grid.Items.Count - 1;
grid.CurrentCell = new DataGridCellInfo(grid.Items[grid.Items.Count - 1], grid.Columns[0]);
}
}
这段代码的作用是，当您 Tab 到最后一行的最后一个单元格并按 Tab 键时，它会将焦点移动到新行的第一个单元格。这是您所期望的，但这不是默认行为。默认行为是将焦点移到下一个控件而不提交当前行编辑。这显然是 DataGrid 中的一个错误，我相信这就是为什么所有提出的解决方案都有一丝杂音。我承认我的解决方案闻起来不太好，但如果您同意这是错误，我更喜欢这种荒谬的默认行为。
即使网格已排序，此解决方案也有效。新输入的行将排序到正确的位置，但焦点将放在新行的第一列。
唯一未解决的问题是，当从顶部向下跳到新行之前的最后一个单元格时，必须输入两次制表符才能将焦点移动到新行。我研究了这个怪癖，最后放弃了。
于 2017-04-26T21:03:27.117 回答