为什么我的列表视图似乎为空？

Question

我是Xamarin Forms和XAML的新手，我想<ListView>与A预约约会。我的XAML如下所示：

<ListView x:Name="appointmentsView"
          ItemsSource="{Binding appointmentList}" 
          Grid.Row="1"
          AbsoluteLayout.LayoutBounds="0.50, 0.2, 1, 0.5"
          AbsoluteLayout.LayoutFlags="All">
    <ListView.ItemTemplate>
        <DataTemplate>
            <ViewCell> 
                <ViewCell.View>
                    <Label TextColor="Black" Text="{Binding app1}"></Label>
                </ViewCell.View>
            </ViewCell>
        </DataTemplate>
    </ListView.ItemTemplate>
</ListView>

代码看起来像这样：

public partial class Home : ContentPage
{
    public ObservableCollection<Appointment> appointmentList = new ObservableCollection<Appointment> ();

    public Employee Tom { get; set; }
    public Appointment app1 { get; set; }

    public Home ()
    {
        InitializeComponent ();

        Tom = new Employee("Tom", "Tommen");
        app1 = new Appointment(new DateTime(), Tom);

        appointmentList.Add(app1);
        appointmentsView.ItemsSource = appointmentList;
    }

调试应用程序时，列表中没有任何内容，如果有人可以告诉我我做错了什么，我将不胜感激！

Answer 1

这实际上取决于Employee和 的Appointment定义方式。例如：

public class Appointment
{
    public DateTime AppointmentDateTime { get; set; }
    public Employee AppointmentEmployee { get; set; }

    public Appointment(DateTime AppointmentDateTime, Employee AppointmentEmployee)
    {
        this.AppointmentDateTime = AppointmentDateTime;
        this.AppointmentEmployee = AppointmentEmployee;
    }
}

public class Employee
{
    public string FirstName { get; set; }
    public string LastName { get; set; }

    public Employee(string FirstName, string LastName)
    {
        this.FirstName = FirstName;
        this.LastName = LastName;
    }

    override public string ToString()
    {
        return string.Format("{0}, {1}", LastName, FirstName);
    }
}

那么你的 XAML 应该是：

<ListView x:Name="appointmentsView"
      ItemsSource="{Binding appointmentList}" 
      Grid.Row="1">
        <ListView.ItemTemplate>
        <DataTemplate>
                <Label Text="{Binding AppointmentEmployee}"></Label>
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>