数据绑定没有错误，但绑定不输出 [英] Data binding no error but the binding is not outputting

问题描述

更新为Matt Lacey ::
C＃代码

Updated for Matt Lacey:: C# code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;
using System.Collections.ObjectModel;

namespace WindowsPhoneApplication1
{
    public partial class MainPage : PhoneApplicationPage
    {
        public MainPage()
        {
            InitializeComponent();
        }

        private void PhoneApplicationPage_Loaded(object sender, System.Windows.RoutedEventArgs e)
        {
            var comments = new Comments();

            var threeComments = new List<Comment>
                                {
                                    new Comment("t1", "d1", "n1", "i1"),
                                    new Comment("t2", "d2", "n2", "i3"),
                                    new Comment("t3", "d3", "n3", "i3")
                                };

            comments.comments = threeComments.ToArray();

            commentsLooper.ItemsSource = new CommentsDataItems(comments);           
        }
    }

    public class Comments
    {
        public Comment[] comments { get; set; }
    }

    public class CommentsDataItems : ObservableCollection<CommentDataItem>
    {
        public CommentsDataItems(Comments comments)
        {
            foreach (var com in comments.comments)
            {
                Add(new CommentDataItem(com.text, com.device, com.name, com.id));
            }
        }
    }

    public class CommentDataItem
    {
        public String text { get; set; }
        public String device { get; set; }
        public String name { get; set; }
        public String id { get; set; }

        public CommentDataItem(String text, String device, String name, String id)
        {
            this.text = text;
            this.device = device;
            this.name = name;
            this.id = id;
        }
    }

    public class Comment
    {
        public String text { get; set; }
        public String device { get; set; }
        public String name { get; set; }
        public String id { get; set; }

        public Comment(String text, String device, String name, String id)
        {
            this.text = text;
            this.device = device;
            this.name = name;
            this.id = id;
        }
    }
}

XAML代码：

<phone:PhoneApplicationPage
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
    xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="800"
    x:Class="WindowsPhoneApplication1.MainPage"
    FontFamily="{StaticResource PhoneFontFamilyNormal}"
    FontSize="{StaticResource PhoneFontSizeNormal}"
    Foreground="{StaticResource PhoneForegroundBrush}"
    SupportedOrientations="Portrait" Orientation="Portrait"
    shell:SystemTray.IsVisible="True" Loaded="PhoneApplicationPage_Loaded">

    <!--LayoutRoot is the root grid where all page content is placed-->
    <Grid x:Name="LayoutRoot" Background="Transparent">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <!--TitlePanel contains the name of the application and page title-->
        <StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,17,0,28">
            <TextBlock x:Name="ApplicationTitle" Text="MY APPLICATION" Style="{StaticResource PhoneTextNormalStyle}" Foreground="White"/>
            <TextBlock x:Name="PageTitle" Text="Test Page" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}" Foreground="White"/>
        </StackPanel>

        <!--ContentPanel - place additional content here-->
        <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
            <ItemsControl x:Name="commentsLooper" Grid.Row="1">
                <ItemsControl.ItemTemplate>
                    <DataTemplate>
                        <TextBlock Height="100" Margin="0" TextWrapping="Wrap" Text="{Binding Text}"/>
                    </DataTemplate>
                </ItemsControl.ItemTemplate>
            </ItemsControl>
        </Grid>
    </Grid>
</phone:PhoneApplicationPage>

推荐答案

我不得不猜测你的某些类型对我来说是以下的工作：

请注意，我已将名称稍稍重命名，并将所有内容放在同一个命名空间中。

I've had to guess at what some of your types are but the following works for me:
Note that I've renamed things slightly and put everything in the same namespace

        var comments = new Comments();

        var threeComments = new List<Comment>
                                {
                                    new Comment("t1", "d1", "n1", "i1"),
                                    new Comment("t2", "d2", "n2", "i3"),
                                    new Comment("t3", "d3", "n3", "i3")
                                };

        comments.comments = threeComments.ToArray();

        commentsLooper.ItemsSource = new CommentsDataItems(comments);


public class Comments
{
    public Comment[] comments { get; set; }
}

public class CommentsDataItems : ObservableCollection<CommentDataItem>
{
    public CommentsDataItems(Comments comments)
    {
        foreach (var com in comments.comments)
        {
            Add(new CommentDataItem(com.text, com.device, com.name, com.id));
        }
    }
}

public class CommentDataItem
{
    public String text { get; set; }
    public String device { get; set; }
    public String name { get; set; }
    public String id { get; set; }

    public CommentDataItem(String text, String device, String name, String id)
    {
        this.text = text;
        this.device = device;
        this.name = name;
        this.id = id;
    }
}

public class Comment
{
    public String text { get; set; }
    public String device { get; set; }
    public String name { get; set; }
    public String id { get; set; }

    public Comment(String text, String device, String name, String id)
    {
        this.text = text;
        this.device = device;
        this.name = name;
        this.id = id;
    }
}

在XAML中，我进行了微小的更改。最大的是删除显式的高度和宽度。值得注意的是，因为您在网格上设置了一个小的关联高度，所以只能看到一个项目。

In the XAML I've made minor changes. The biggest of which was to remove the explicit heights and widths. Notably because you'd set a small relateive height on the grid there was only room to see one item.

<Grid x:Name="commentsCotainer" VerticalAlignment="Top">
    <ItemsControl x:Name="commentsLooper" Grid.Row="1">
        <ItemsControl.ItemTemplate>
            <DataTemplate>
                <Grid x:Name="comentHolder" HorizontalAlignment="Center" VerticalAlignment="Top">
                    <TextBlock HorizontalAlignment="Stretch" VerticalAlignment="Top" TextWrapping="Wrap" Text="{Binding text}" Foreground="White" />
                </Grid>
            </DataTemplate>
        </ItemsControl.ItemTemplate>
    </ItemsControl>
</Grid>

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