c# - XAML 中的 WPF ListView 绑定(bind) ItemsSource

Question

我有一个简单的 XAML 页面，上面有一个 ListView，定义如下

<ListView Margin="10" Name="lvUsers" ItemsSource="{Binding People}">
    <ListView.View>
        <GridView>
            <GridViewColumn Header="Name" Width="120" DisplayMemberBinding="{Binding Name}" />
            <GridViewColumn Header="Age" Width="50" DisplayMemberBinding="{Binding Age}" />
            <GridViewColumn Header="Mail" Width="150" DisplayMemberBinding="{Binding Mail}" />
        </GridView>
    </ListView.View>
</ListView> 

在我后面的代码中:-

public ObservableCollection<Person> People { get; set; }

public ListView()
{
    InitializeComponent();

    this.People = new ObservableCollection<Person>();
    this.People.Add(new Person() { Name = "John Doe", Age = 42, Mail = "john@doe-family.com" });
    this.People.Add(new Person() { Name = "Jane Doe", Age = 39, Mail = "jane@doe-family.com" });
    this.People.Add(new Person() { Name = "Sammy Doe", Age = 7, Mail = "sammy.doe@gmail.com" }); 

}   

如果我像这样在后面的代码中设置我的 ListView 的 ItemsSource

lvUsers.ItemsSource = this.People;

它工作正常并且我的网格按预期显示

但是，如果我删除该行并尝试在 XAML 中进行绑定(bind)

<ListView Margin="10" Name="lvUsers" ItemsSource="{Binding People}">

它不再有效。

为什么 XAML 中的绑定(bind)不起作用？

Answer 1

如果您还没有这样做，例如在 XAML 中，您需要为您的绑定(bind)设置 DataContext。此外，由于 People 属性未实现 INotifyPropertyChanged，您可能希望在 InitializeComponent 之前创建此列表，至少在设置 DataContext< 之前，以确保在评估绑定(bind)时列表已准备就绪。您可以稍后添加到您的 ObservableCollection，但如果您在那之后创建它而不通知 UI，它将无法工作

public ListView()
{
    this.People = new ObservableCollection<Person>();
    InitializeComponent();
    this.DataContext = this;

    this.People.Add(new Person() { Name = "John Doe", Age = 42, Mail = "john@doe-family.com" });
    this.People.Add(new Person() { Name = "Jane Doe", Age = 39, Mail = "jane@doe-family.com" });
    this.People.Add(new Person() { Name = "Sammy Doe", Age = 7, Mail = "sammy.doe@gmail.com" }); 
}