绑定到组合框控件模板项失败

Question

我正在使用组合框并通过List值绑定，如下所示

    <ComboBox ItemsSource="{Binding}" Name="testCombo" Margin="67,48,184,204">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <TextBox  Text="{Binding RelativeSource={RelativeSource FindAncestor,AncestorType=ComboBox},Mode=OneWay,Path=SelectedItem}" Width="100" Height="50" />
            </DataTemplate>
        </ComboBox.ItemTemplate>            
    </ComboBox>

c＃中的绑定数据如下所示

      IList<string> objLoadData = new List<String> { "Ramesh", "Suresh" };
      testCombo.DataContext = objLoadData;    

我试图将数据绑定到文本框中，但我不能。 如何将数据绑定到文本框？

Answer 1

如果你的列表只是字符串，那么Text="{Binding}"可以了

您应该考虑为ItemsSource使用ObservableCollection ，因为它会在Items更改时自动更新ComboBox （添加/删除等）

<Window x:Class="WpfApplication13.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525" Name="UI">
    <Grid DataContext="{Binding ElementName=UI}">
        <ComboBox ItemsSource="{Binding ComboItems}" Margin="67,48,184,204">
            <ComboBox.ItemTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding}" Width="100" Height="50" />
                </DataTemplate>
            </ComboBox.ItemTemplate>
        </ComboBox>
    </Grid>
</Window>

码：

public partial class MainWindow : Window
{
    private ObservableCollection<string> _comboItems = new ObservableCollection<string>();

    public MainWindow()
    {
        InitializeComponent();
        ComboItems.Add("Stack");
        ComboItems.Add("Overflow");
    }

    public ObservableCollection<string> ComboItems
    {
        get { return _comboItems; }
        set { _comboItems = value; }
    }
}

如果你想在ComboBox使用TextBox ，你可能希望使用一个对象作为实现INotifyPropertyChanged的字符串的后备存储，这样eveyything就会被更新并保持同步。

例：

<Window x:Class="WpfApplication13.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525" Name="UI">
    <Grid DataContext="{Binding ElementName=UI}">
        <ComboBox ItemsSource="{Binding ComboItems}" Margin="67,48,184,204">
            <ComboBox.ItemTemplate>
                <DataTemplate>
                    <TextBox Text="{Binding Name}" Width="100" Height="50" />
                </DataTemplate>
            </ComboBox.ItemTemplate>
        </ComboBox>
    </Grid>
</Window>

码：

public partial class MainWindow : Window
{
    private ObservableCollection<MyItem> _comboItems = new ObservableCollection<MyItem>();

    public MainWindow()
    {
        InitializeComponent();
        ComboItems.Add(new MyItem { Name = "Stack" });
        ComboItems.Add(new MyItem { Name = "Overflow" });
    }

    public ObservableCollection<MyItem> ComboItems
    {
        get { return _comboItems; }
        set { _comboItems = value; }
    }
}

public class MyItem : INotifyPropertyChanged
{
    private string _name;
    public string Name
    {
        get { return _name; }
        set { _name = value; NotifyPropertyChanged("Name"); }
    }


    public event PropertyChangedEventHandler PropertyChanged;
    private void NotifyPropertyChanged(string property)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(property));
        }
    }
}

Answer 2

尝试这个;

内部构造

testCombo.DataContext = this;
testCombo.ItemsSource = objLoadData;  

在XAML中

   <ComboBox Name="testCombo" Width="100" Height="50" >
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <TextBox Text="{Binding Mode=OneWay}" Width="100" Height="50" />
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>