c# - Xamarin.Forms 填充 ListView

Question

我正在尝试创建一个带有 ListView 和 Button“添加”的简单页面，它只是将另一个项目添加到列表中，并带有计数和时间戳.

App.cs

namespace App1
{
    public class App : Application
    {
        public App()
        {
            // The root page of your application
            MainPage = new NavigationPage(new Page1());
        }
    }
}

如您所见，我创建了一个 Page.xaml 和 Page.xaml.cs。

Page.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="App1.Page1">
  <StackLayout Orientation="Vertical" VerticalOptions="FillAndExpand">
    <Label Text="Inizio" VerticalOptions="Start"/>
    <ListView VerticalOptions="FillAndExpand" x:Name ="list">
    </ListView>
    <Label Text="Fine" VerticalOptions="End"/>
  </StackLayout>
  <ContentPage.ToolbarItems>
    <ToolbarItem x:Name="add">
      <ToolbarItem.Icon>
        <OnPlatform
          x:TypeArguments="FileImageSource"
          iOS="appbar.add.png"
          Android="appbar.add.png"
          WinPhone="appbar.add.png"
        />
      </ToolbarItem.Icon>
    </ToolbarItem>
  </ContentPage.ToolbarItems>
</ContentPage>

Page.xaml.cs

namespace App1
{
    public partial class Page1 : ContentPage
    {
        int count = 0;
        ObservableCollection<TextCell> cells = new ObservableCollection<TextCell>();

        public Page1()
        {
            InitializeComponent();
            //this.ToolbarItems.Add(new ToolbarItem { Text = "Add" });
            add.Clicked += Add_Clicked;
        }

        private void Add_Clicked(object sender, EventArgs e)
        {
            cells.Add(new TextCell { Text = count.ToString(), Detail = DateTime.Now.ToString("dd/MM/yyyy --> hh:mm:ss") });
            list.ItemsSource = cells; 
            count++;
        }
    }
}

现在，一切正常，但问题是 List。我的 List 中填充了 TextCells，并且它们中的每一个都具有我设置的属性。但是，List 由仅包含文本“Xamarin.Forms.TextCell”的元素填充。

这是我第一次尝试使用 Xamarin，我做错了什么？

Answer 1

你必须定义一个项目模板

这是 Xamarin 文档的示例

class Person
{
  public string FullName
  {
    get;
    set;
  }

  public string Address
  {
    get;
    set;
  }
}

void SetupView()
{
  var template = new DataTemplate (typeof (TextCell));

  // We can set data bindings to our supplied objects.
  template.SetBinding (TextCell.TextProperty, "FullName");
  template.SetBinding (TextCell.DetailProperty, "Address");

  // We can also set values that will apply to each item.
  template.SetValue (TextCell.TextColorProperty, Color.Red);

  itemsView.ItemTemplate = template;
  itemsView.ItemsSource = new[] {
    new Person { FullName = "James Smith", Address = "404 Nowhere Street" },
    new Person { FullName = "John Doe", Address = "404 Nowhere Ave" }
  };
}