Question

我正在尝试在this tutorial之后通过WCF填充Longlist。我想按收入（从最小到最大）对用户进行分组，但是随机显示组。列表中也没有项目（见下图）。我错过了什么？我的XAML代码是：

<phone:PhoneApplicationPage.Resources>
    <phone:JumpListItemBackgroundConverter x:Key="BackgroundConverter"/>
    <phone:JumpListItemForegroundConverter x:Key="ForegroundConverter"/>
    <DataTemplate x:Key="usersHeaderTemplate">
        <Border Width="72" Height="72" HorizontalAlignment="Left" Background="{Binding Converter={StaticResource BackgroundConverter}}" Margin="6">
            <TextBlock Text="{Binding Income}"
               FontSize="20" Padding="6"
               VerticalAlignment="Center" HorizontalAlignment="Center"
               Foreground="{Binding Converter={StaticResource ForegroundConverter}}" />
        </Border>
    </DataTemplate>
    <DataTemplate x:Key="usersItemTemplate">
        <StackPanel Orientation="Horizontal">
            <Image Source="{Binding Flag}"  Height="50" Margin="0,0,10,0"/>
            <StackPanel>
                <TextBlock Text="{Binding Name}" Style="{StaticResource PhoneTextSubtleStyle}" />
                <TextBlock Text="{Binding Income,StringFormat='Income: {0}'}" />
                <TextBlock Text="{Binding Job}"/>
            </StackPanel>
        </StackPanel>
    </DataTemplate>
    <Style x:Key="LongListSelectorJumpListStyle" TargetType="phone:LongListSelector">
        <Setter Property="GridCellSize"  Value="113,113"/>
        <Setter Property="LayoutMode" Value="Grid" />
        <Setter Property="ItemTemplate">
            <Setter.Value>
                <DataTemplate>
                    <Border Background="{Binding Converter={StaticResource BackgroundConverter}}"
                                    Width="113" Height="113" Margin="6" >
                        <TextBlock Text="{Binding Title}"
                                           FontFamily="{StaticResource PhoneFontFamilySemiBold}"
                                           FontSize="48" Padding="6"
                                           Foreground="{Binding Converter={StaticResource ForegroundConverter}}"
                                           VerticalAlignment="Center"/>
                    </Border>
                </DataTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <DataTemplate x:Key="usersListHeader">
        <Border Background="White" Opacity="0.2" Height="70">
            <TextBlock Text="List Header" VerticalAlignment="Center" HorizontalAlignment="Center" Foreground="Black" />
        </Border>
    </DataTemplate>
    <DataTemplate x:Key="usersListFooter">
        <Border Background="White" Opacity="0.2" Height="70">
            <TextBlock Text="List Footer" VerticalAlignment="Center" HorizontalAlignment="Center" Foreground="Black"/>
        </Border>
    </DataTemplate>

</phone:PhoneApplicationPage.Resources>
<Grid x:Name="LayoutRoot" Background="Transparent">
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto"/>
        <RowDefinition Height="*"/>
    </Grid.RowDefinitions>
    <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
        <phone:LongListSelector x:Name="longlist2" Height="608" Margin="10,15,24,0" VerticalAlignment="Top" Width="422"
IsGroupingEnabled="True" LayoutMode="List" HideEmptyGroups="False"
ItemTemplate="{StaticResource usersItemTemplate}"
GroupHeaderTemplate="{StaticResource usersHeaderTemplate}"
JumpListStyle="{StaticResource LongListSelectorJumpListStyle}"
ListHeaderTemplate="{StaticResource usersListHeader}"
ListFooterTemplate="{StaticResource usersListFooter}" >
        </phone:LongListSelector>
    </Grid>
</Grid>

我的服务实施是：

public IEnumerable<mTeachers> GetStuffList(string Job)
    {
        List<mTeachers> stuffList = new List<mTeachers>();
        DataClasses1DataContext data = new DataClasses1DataContext();
        List<mTeachers> finalList = new List<mTeachers>();
            foreach (var d in data.Stuffs)
            {
                stuffList.Add(new mTeachers() { Name = d.stuffName, Income = (int)d.stuffIncome, Job = Job, Flag = new Uri(@"/Assets/users.png", UriKind.Relative) });               
            }
                return stuffList;              
    }
  private List<Group<mTeachers>> GetUsersGroups(string Job)
    {
        IEnumerable<mTeachers> usersList = GetStuffList(Job);
        return GetItemGroups(usersList, c => c.Income);
    }
    private static List<Group<T>> GetItemGroups<T>(IEnumerable<T> itemList, Func<T, int> getKeyFunc)
    {
        IEnumerable<Group<T>> groupList = from item in itemList
                                                  group item by getKeyFunc(item) into g
                                                  orderby g.Key
                                                  select new Group<T>(g.Key, g);
        return groupList.ToList();
    }
    public class Group<T> : List<T>
    {
        public Group(int income, IEnumerable<T> items)
            : base(items)
        {
            this.Income = income;
        }

        public int Income
        {
            get;
            set;
        }
    }

我的服务界面：

 [OperationContract]
    IEnumerable<mTeachers> GetStuffList(string Job);
    }
[DataContract]
public class mTeachers
{
    [DataMember]
    public string Name { get; set; }
    [DataMember]
    public int Income { get; set; }
    [DataMember]
    public string Job { get; set; }
    [DataMember]
    public System.Uri Flag { get; set; }
}

编辑： WP页面代码：

 public MainPage()
    {
        InitializeComponent();  
        ServiceReference1.Service1Client proxy = new ServiceReference1.Service1Client();
        proxy.GetStuffListCompleted += showList;
        proxy.GetStuffListAsync("teacher");
    }
    private void showList(object sender, ServiceReference1.GetStuffListCompletedEventArgs e)
    {
      this.longlist2.ItemsSource = e.Result; 
    }

my screenshot

Answer 1

将ItemsSource="{Binding}"添加到XAML中的LongListSelector声明中。所以看起来应该是这样的。

<phone:LongListSelector x:Name="longlist2" Height="608" Margin="10,15,24,0" VerticalAlignment="Top" Width="422"
                        IsGroupingEnabled="True" LayoutMode="List" HideEmptyGroups="False"
                        ItemTemplate="{StaticResource usersItemTemplate}"
                        GroupHeaderTemplate="{StaticResource usersHeaderTemplate}"
                        JumpListStyle="{StaticResource LongListSelectorJumpListStyle}"
                        ListHeaderTemplate="{StaticResource usersListHeader}"
                        ListFooterTemplate="{StaticResource usersListFooter}"
                        ItemsSource="{Binding}" >
</phone:LongListSelector>

Answer 2

我认为这里有两件事情。

首先我认为你的GetStuffList（字符串Job）函数做了一些奇怪的事情，请检查返回值，看看它是否正是你想要的。

其次我认为ItemSource需要像KasunKV那样设置。

以下是我的修补程序以及显示其有效的结果屏幕截图。

// create a static group list to see if it works
private List<Group<mTeachers>> GetUsersGroups(string Job)
{
    List<mTeachers> usersList = new List<mTeachers>();

    usersList.Add(new mTeachers() { Name = "Bob", Income = 1000, Flag = new Uri(@"/Assets/AlignmentGrid.png", UriKind.Relative),  Job = "Guy" });
    usersList.Add(new mTeachers() { Name = "Dan", Income = 1000, Flag = new Uri(@"/Assets/AlignmentGrid.png", UriKind.Relative), Job = "Guy" });
    usersList.Add(new mTeachers() { Name = "Kate", Income = 2000, Flag = new Uri(@"/Assets/AlignmentGrid.png", UriKind.Relative), Job = "Girl" });
    usersList.Add(new mTeachers() { Name = "Charlie", Income = 2000, Flag = new Uri(@"/Assets/AlignmentGrid.png", UriKind.Relative), Job = "Guy" });
    usersList.Add(new mTeachers() { Name = "Jeff", Income = 2000, Flag = new Uri(@"/Assets/AlignmentGrid.png", UriKind.Relative), Job = "Guy" });
    usersList.Add(new mTeachers() { Name = "Jeff2", Flag = new Uri(@"/Assets/AlignmentGrid.png", UriKind.Relative), Job = "Guy" });
    return GetItemGroups(usersList, c => c.Income);
}


// Constructor
public MainPage()
{
    InitializeComponent();

    // create the user group and bind it to item source
    this.longlist2.ItemsSource = GetUsersGroups("whatever");
}

可以在此处查看更改结果：

enter image description here

Longlist没有填充项目

2 个答案: