如何将ObservableCollection绑定到DataTemplate中的TextBoxes？

Question

我试图成功地将一个ObservableCollection绑定到DataTemplate中的TextBoxes.我可以正确显示数据,但我无法通过UI更改列表数据.我有一个名为'model'的Model类,它包含一个名为'List'的ObservableCollection.该类实现了INotifyPropertyChanged接口.这是shell的xaml.Window1网格的DataContext设置为"theGrid.DataContext = model"

<Window x:Class="BindThat.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:BindThat"
Title="Window1" Height="300" Width="300">
<StackPanel x:Name="theGrid">
    <GroupBox BorderBrush="LightGreen">
        <GroupBox.Header>
            <TextBlock Text="Group" />
        </GroupBox.Header>
        <ItemsControl ItemsSource="{Binding Path=List}">
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <TextBox Text="{Binding Path=., Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </GroupBox> 
</StackPanel>

这是Model类的代码:

class Model : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    private void NotifyPropertyChanged(string name)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(name));
    }

    private ObservableCollection<string> _list = new ObservableCollection<string>();
    public ObservableCollection<string> List
    {
        get { return _list; }
        set 
        { 
            _list = value;
            NotifyPropertyChanged("List");
        }
    }

    public Model()
    {
        List.Add("why");
        List.Add("not");
        List.Add("these?");
    }
}

任何人都可以建议我是否正确的方式？

Answer 1

你需要一个属性绑定两个方式,所以字符串不适合这个.

将它包装在一个字符串对象中,如下所示:

public class Model
{
    public ObservableCollection<StringObject> List { get; private set; }
    public Model()
    {
        List = new ObservableCollection<StringObject>
                   {
                       new StringObject {Value = "why"},
                       new StringObject {Value = "not"},
                       new StringObject {Value = "these"},
                   };
    }
}

public class StringObject
{
    public string Value { get; set; }
}

并绑定到Value属性而不是"."

此外,您不需要通知可观察集合的更改,因此在您的模型具有其自身的某些其他属性之前,它不需要具有INotifyPropertyChange.如果您希望ItemsControl对单个StringObjects中的更改做出反应,则应将INotifyPropertyChanged添加到StringObject.

而且,双向绑定是默认的,所以你只需要

<TextBox Text="{Binding Path=Value}" />

在你的绑定.