Question

在我的应用程序中，我以编程方式生成数据网格并将其与列表绑定。我能够在datagrid中看到数据，但是当我编辑单元格时，列表中的基础项目不会更新。这是代码

Window dateChangeWindow = new Window();
dateChangeWindow.WindowStartupLocation = WindowStartupLocation.CenterOwner;
dateChangeWindow.Owner = Application.Current.MainWindow;
dateChangeWindow.SizeToContent = SizeToContent.WidthAndHeight;
dateChangeWindow.Title = "Date Change";

StackPanel stackPanel = new StackPanel();
stackPanel.Orientation = Orientation.Vertical;

DataGrid requestGrid = new DataGrid();
requestGrid.CanUserResizeColumns = false;
requestGrid.CanUserResizeRows = false;
requestGrid.CanUserReorderColumns = false;
requestGrid.CanUserSortColumns = true;
requestGrid.AutoGenerateColumns = false;

DataGridTextColumn requestIdColumn = new DataGridTextColumn();
requestIdColumn.Header = "Request Id";
Binding idBinding = new Binding("RequestId");
idBinding.Mode = BindingMode.OneWay;
requestIdColumn.Binding = idBinding;
requestGrid.Columns.Add(requestIdColumn);

DataGridTemplateColumn startDateColumn = new DataGridTemplateColumn();
startDateColumn.Header = "Start Date";
Binding startDateBinding = new Binding("StartDate");
startDateBinding.Mode = BindingMode.TwoWay;
FrameworkElementFactory startDateFactory = new FrameworkElementFactory(typeof(DatePicker));
startDateFactory.SetBinding(DatePicker.SelectedDateProperty, startDateBinding);
DataTemplate startDateTemplate = new DataTemplate();
startDateTemplate.VisualTree = startDateFactory;
startDateColumn.CellTemplate = startDateTemplate;
startDateColumn.CellEditingTemplate = startDateTemplate;
requestGrid.Columns.Add(startDateColumn);

DataGridTemplateColumn endDateColumn = new DataGridTemplateColumn();
endDateColumn.Header = "End Date";
Binding endDateBinding = new Binding("EndDate");
endDateBinding.Mode = BindingMode.TwoWay;
FrameworkElementFactory endDateFactory = new FrameworkElementFactory(typeof(DatePicker));
endDateFactory.SetBinding(DatePicker.SelectedDateProperty, endDateBinding);
DataTemplate endDateTemplate = new DataTemplate();
endDateTemplate.VisualTree = endDateFactory;
endDateColumn.CellTemplate = endDateTemplate;
endDateColumn.CellEditingTemplate = endDateTemplate;
requestGrid.Columns.Add(endDateColumn);

requestGrid.ItemsSource = requestList;
requestGrid.Margin = new Thickness(0, 10, 0, 0);
requestGrid.HorizontalAlignment = HorizontalAlignment.Center;

stackPanel.Children.Add(requestGrid);

Button changeDoneBtn = new Button();
changeDoneBtn.Content = "Submit";
changeDoneBtn.Click += new RoutedEventHandler(changeDone_Click);
changeDoneBtn.Margin = new Thickness(0, 20, 0, 10);
changeDoneBtn.HorizontalAlignment = HorizontalAlignment.Center;

stackPanel.Children.Add(changeDoneBtn);

dateChangeWindow.Content = stackPanel;
dateChangeWindow.ShowDialog();

在创建窗口之前填充ItemsSource requestList。它被声明为

IList<DateChangeWrapper> requestList = new List<DateChangeWrapper>();

DateChangeWrapper类看起来像这样

public class DateChangeWrapper : INotifyPropertyChanged
{
    public DateChangeWrapper(ResponseWrapper responseWrapper)
    {
        RequestId = responseWrapper.RequestId;
        ParentRequestId = responseWrapper.ParentRequestId;
        StartDate = responseWrapper.StartDate;
        EndDate = responseWrapper.EndDate;
    }

    private DateTime startDate;
    private DateTime endDate;

    public int RequestId { get; private set; }
    public int ParentRequestId { get; private set; }

    public DateTime StartDate
    {
        get { return startDate; }
        set
        {
            startDate = value;
            OnPropertyChanged("StartDate");
        }
    }

    public DateTime EndDate
    {
        get { return endDate; }
        set
        {
            endDate = value;
            OnPropertyChanged("EndDate");
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;  

    private void OnPropertyChanged(string propertyName)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null)
        {
            var e = new PropertyChangedEventArgs(propertyName);
            handler(this, e);
        }
    }
}

从代码中可以看出，我有两列StartDate和EndDate显示为DatePickers。当我调试代码时，调用window.ShowDialog的点，我看到日期的get访问器被调用。但是当我更改datepicker中的值时，setter不会被调用，我的列表仍然具有旧值。

请帮帮我

Answer 1

问题在于，由于UpdateSourceTrigger，更改后的值未更新回基础源。默认情况下，它具有LostFocus的值。我将其更改为PropertyChanged并且它有效！：）

我将以下代码行添加到我的绑定

startDateBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;

，类似于EndDate

WPF数据绑定在编程生成的DataGrid中没有正确发生

1 个答案: