在XAML中将可观察对象集合绑定到ListBox

本文关键字：集合 绑定 ListBox 对象 观察 XAML | 更新日期: 2023-09-27 18:10:45

我花了很多时间来解决这个问题。

我有一个类的数据:

public class User : INotifyPropertyChanged
{
    private int _key;
    private string _fullName;
    private string _nick;
    public int Key
    {
        get{return _key;}
        set { _key = value; NotifyPropertyChanged("Key"); }
    }
    public string Nick
    {
        get { return _nick; }
        set { _nick = value; NotifyPropertyChanged("Nick"); }
    }
    public string FullName
    {
        get { return _fullName; }
        set { _fullName = value; NotifyPropertyChanged("FullName"); }
    }

    public User()
    {
        Nick = "nickname";
        FullName = "fullname";
    }
    public User(String nick, String name, int key)
    {
        Nick = nick;
        FullName  = name;
    }

    //INotifyPropertyChanged implementation
    public event PropertyChangedEventHandler PropertyChanged;
    private void NotifyPropertyChanged(String propertyName)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }
    public override string ToString() 
    { 
        return string.Format("{0} {1}, {2}", Key, Nick, FullName); 
    }
}

接下来我有一个类userClass的observablecollection:

public class UserList : ObservableCollection<UserList>
{
    public UserList (){}
    ~UserList ()
    {
        //Serialize();
    }
    public void Serialize(ObservableCollection<UserList> usersColl) 
    {
        FileStream fs = new FileStream("DataFile.dat", FileMode.Create);
        BinaryFormatter formatter = new BinaryFormatter();
        try
        {
            formatter.Serialize(fs, usersColl);
        }
        catch (SerializationException e)
        {
            Console.WriteLine("Failed to serialize. Reason: " + e.Message);
            throw;
        }
        finally
        {
            fs.Close();
        }
    }
    public void Deserialize() 
    {
        FileStream fs = new FileStream("DataFile.dat", FileMode.Open);
        try 
        {
            BinaryFormatter formatter = new BinaryFormatter();
            //users = (Hashtable) formatter.Deserialize(fs);
            //usersColl = (ObservableCollection<userClass>)formatter.Deserialize(fs);
        }
        catch (SerializationException e) 
        {
            MessageBox.Show(" Error: " + e.Message);
            throw;
        }
        finally 
        {
            fs.Close();
        }
    }
}

事实上，经过大量的测试和编辑后，大部分代码无法工作，比如序列化。但是数据绑定是不必要的，绑定是我现在正在解决的问题。

所以我有这个集合，并希望将其绑定到listBox。我试了好几种方法，但都没用。

我最后一次尝试给我写错误:

资源'users'无法解析。

<ListBox Grid.Column="0" Name="userViewLeft" ItemsSource="{Binding Source={StaticResource users} }" />

在XAML中将可观察对象集合绑定到ListBox

注意事项

  • 设置属性为public而不是private。
  • Make Variables . private .
  • 遵循命名规范，不要在类后面添加class。
  • ItemsSource你提供的应该是根据数据的范围，在我的例子中，类范围内的用户列表和我已经提供了ItemSource on Window Loaded事件。

这是一个完整的示例代码，在这里我已经嵌套了网格控件在ListBox，因为以后你可以改变ListBox属性VirtualizingStackPanel。因此，当列表上有大量更新时，它将提供巨大的性能提升。你也可以使用BindingList，在我看来，它比ObservableCollection性能更好。

用户类: 

    public class User : INotifyPropertyChanged
    {
        private int _key;
        private string _fullName;
        private string _nick;
        public int Key
        {
            get { return _key; }
            set { _key = value; NotifyPropertyChanged("Key"); }
        }
        public string NickName
        {
            get { return _nick; }
            set { _nick = value; NotifyPropertyChanged("NickName"); }
        }
        public string Name
        {
            get { return _fullName; }
            set { _fullName = value; NotifyPropertyChanged("Name"); }
        }
        public User(String nick, String name, int key)
        {
            this.NickName = nick;
            this.Name = name;
            this.Key = key; 
        }
        public event PropertyChangedEventHandler PropertyChanged;
        private void NotifyPropertyChanged(String propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
        public override string ToString()
        {
            return string.Format("{0} {1}, {2}", Key, NickName, Name);
        }
    }

用户列表类:

    public class Users : ObservableCollection<User>
    {
        public Users()
        {
            Add(new User("Jamy", "James Smith", Count));
            Add(new User("Mairy", "Mary Hayes", Count));
            Add(new User("Dairy", "Dary Wills", Count));
        }
    }

XAML: 

   <Grid>
        <Button Content="Start" Height="23" HorizontalAlignment="Left" Margin="416,12,0,0" x:Name="button1" VerticalAlignment="Top" Width="75" Click="button1_Click" />
        <ListBox x:Name="UserList" HorizontalContentAlignment="Stretch" Margin="12,41,12,12">
            <ListBox.ItemTemplate>
                <DataTemplate>
                        <Grid Margin="10">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="20" />
                                <ColumnDefinition Width="150" />
                                <ColumnDefinition Width="*" />
                            </Grid.ColumnDefinitions>
                            <TextBlock Text="{Binding Key}" Margin="3" Grid.Column="0" />
                            <TextBlock Text="{Binding NickName}" Margin="3" Grid.Column="1" />
                            <TextBlock Text="{Binding Name}" Margin="3" Grid.Column="2" />
                        </Grid>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
    </Grid>

XAML Code behind:

public partial class MainWindow : Window
{
    public static Users userslist = new Users();
    DispatcherTimer timer = new DispatcherTimer();
    public MainWindow()
    {
        InitializeComponent();
        this.Loaded += new RoutedEventHandler(MainWindow_Loaded);
    }
    void MainWindow_Loaded(object sender, RoutedEventArgs e)
    {
        timer.Interval = DateTime.Now.AddSeconds(10) - DateTime.Now;
        timer.Tick += new EventHandler(timer_Tick);
        UserList.ItemsSource = userslist;
    }
    void timer_Tick(object sender, EventArgs e)
    {
        userslist.Add(new User("Jamy - " + userslist.Count, "James Smith", userslist.Count));
        userslist.Add(new User("Mairy - " + userslist.Count, "Mary Hayes", userslist.Count));
        userslist.Add(new User("Dairy - " + userslist.Count, "Dary Wills", userslist.Count));
    }
    private void button1_Click(object sender, RoutedEventArgs e)
    {
        if (button1.Content.ToString() == "Start")
        {
            button1.Content = "Stop";
            timer.Start();
        }
        else
        {
            button1.Content = "Start";
            timer.Stop();
        }
    }
}

你需要做两件事:

首先，将包含ListBox的任何元素(Window/UserControl/whatever)的DataContext设置为如下对象: 
public class ViewModel
{
    public ViewModel() { this.users = new userListClass(); }
    public userListClass users { get; private set; }
}

这是你的视图模型，也是你想要绑定到的。

其次，将绑定更改为ItemsSource="{Binding Path=users}"。这转换为"将我的ItemsSource属性的值设置为this.DataContext上的users属性的值"。因为DataContext继承自父类，并且您将其设置为上面的ViewModel类，所以您的ListBox现在将显示您的用户列表。

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