GridView中的双向数据绑定

Question

我们有一个应用程序使用简单的单向绑定与GridView来显示一些数据.好吧,现在我们需要允许用户更改一些数据,所以我一直试图让双向数据绑定在GridView中工作.到目前为止,一切都正确显示,但在GridView中编辑单元格似乎什么都不做.我搞砸了什么？像这样的双向数据绑定甚至可能吗？我应该开始转换所有内容以使用不同的控件,比如DataGrid吗？

我写了一个小测试应用程序,显示我的问题.如果您尝试它,您将看到属性设置器在初始化后永远不会被调用.

XAML:

    Title="Window1" Height="300" Width="300">
    <Grid>
        <ListView Name="TestList">
            <ListView.View>
                <GridView>
                    <GridViewColumn Header="Strings">
                        <GridViewColumn.CellTemplate>
                            <DataTemplate>
                                <TextBox Text="{Binding Path=String, Mode=TwoWay}"/>
                            </DataTemplate>
                        </GridViewColumn.CellTemplate>
                    </GridViewColumn>
                    <GridViewColumn Header="Bools">
                        <GridViewColumn.CellTemplate>
                            <DataTemplate>
                                <CheckBox IsChecked="{Binding Path=Bool, Mode=TwoWay}"/>
                            </DataTemplate>
                        </GridViewColumn.CellTemplate>
                    </GridViewColumn>
                </GridView>
            </ListView.View>
        </ListView>
    </Grid>
</Window>

这是相应的代码:

using System.Collections.Generic;
using System.Windows;

namespace GridViewTextbox
{
    public partial class Window1 : Window
    {
        private List<TestRow> _rows = new List<TestRow>();

        public Window1()
        {
            InitializeComponent();

            _rows.Add(new TestRow("a", false));
            _rows.Add(new TestRow("b", true));
            _rows.Add(new TestRow("c", false));

            TestList.ItemsSource = _rows;
            TestList.DataContext = _rows;
        }
    }

    public class TestRow : System.Windows.DependencyObject
    {
        public TestRow(string s, bool b)
        {
            String = s;
            Bool = b;
        }

        public string String
        {
            get { return (string)GetValue(StringProperty); }
            set { SetValue(StringProperty, value); }
        }

        // Using a DependencyProperty as the backing store for String.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty StringProperty =
            DependencyProperty.Register("String", typeof(string), typeof(TestRow), new UIPropertyMetadata(""));


        public bool Bool
        {
            get { return (bool)GetValue(BoolProperty); }
            set { SetValue(BoolProperty, value); }
        }

        // Using a DependencyProperty as the backing store for Bool.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty BoolProperty =
            DependencyProperty.Register("Bool", typeof(bool), typeof(TestRow), new UIPropertyMetadata(false));
    }
}

Answer 1

使用依赖项属性时,不会通过绑定调用Setter,而是直接更改值(使用SetValue或类似的东西).

尝试添加PropertyChangedCallback,并在其中设置断点以查看是否从GridView更改了值.

public static readonly DependencyProperty BoolProperty =
    DependencyProperty.Register("Bool", typeof(bool), typeof(TestRow), new UIPropertyMetadata(false, OnBoolChanged));
private static void OnBoolChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
    //this method will be called everytime Bool changes value
}