Telerik RadJumpList using DataVirtualizationMode.Automatic

我有一个问题，我试图使用一个teleerik跳转列表与DataVirtualizationMode。是自动的，但我开不了。我想使用这个的原因是因为我希望我的应用程序只下载数据(游戏)，这是在跳转列表控件的当前视图，而不是整个数据每次。例如，如果我搜索"蝙蝠侠"，它返回50个游戏，我不希望它下载和加载所有游戏，只下载那些我可以在跳转列表控件中看到的游戏。

下面是一个使用DataVirtualizationMode的示例。自动从Telerik，但我不能让它与我的应用程序工作:http://www.telerik.com/help/windows-phone/raddataboundlistbox-features-datavirtualization-automatic.html

下面是我的跳跃列表控件，我想在数据虚拟化中使用。

MainPage.xaml:

<phone:PivotItem Header="Browse">
            <Grid>
                <telerikPrimitives:RadTextBox Name="txtSearch" HorizontalAlignment="Left" VerticalAlignment="Top" Height="80" Width="390"/>
                <telerikPrimitives:RadImageButton Name="imgBtnSeachGame" VerticalAlignment="Top" HorizontalAlignment="Right" ButtonShape="Ellipse" BorderThickness="2" Margin="0,8,0,0" Click="imgBtnSeachGame_Click"></telerikPrimitives:RadImageButton>
                <Controls:RadJumpList Name="jlGameList" ItemsSource="{Binding}" Tap="jlGameList_Tap" Margin="0,90,0,0" DataVirtualizationMode="Automatic">
                    <Controls:RadJumpList.ItemTemplate>
                        <DataTemplate>
                            <Grid>
                                <Grid.RowDefinitions>
                                    <RowDefinition Height="Auto"></RowDefinition>
                                    <RowDefinition Height="*"></RowDefinition>
                                    <RowDefinition Height="20"></RowDefinition>
                                </Grid.RowDefinitions>
                                <Border Grid.Row="0" Background="{StaticResource PhoneAccentBrush}" 
        Padding="{StaticResource PhoneTouchTargetOverhang}"
        Margin="0,0,0,0">
                                    <TextBlock Name="tblGameTitle" Style="{StaticResource PhoneTextGroupHeaderStyle}" ManipulationStarted="tblGameTitle_ManipulationStarted" ManipulationCompleted="tblGameTitle_ManipulationCompleted">
                                        <Run Text="{Binding GameTitle}"></Run>
                                    </TextBlock>
                                </Border>
                                <Grid Background="#242424" Grid.Row="1">
                                    <Image Name="imgGameList" Margin="0,0,0,0" Stretch="Fill" HorizontalAlignment="Left" VerticalAlignment="Top" Height="96" Width="96">
                                        <Image.Source>
                                            <BitmapImage UriSource="{Binding BoxArtFrontThumb}"
                                 CreateOptions="BackgroundCreation" DecodePixelHeight="96" DecodePixelWidth="96" />
                                        </Image.Source>
                                    </Image>
                                    <TextBlock Margin="110,0,0,0" Text="Platform" FontWeight="Bold" TextWrapping="Wrap" Foreground="YellowGreen" FontSize="{StaticResource PhoneFontSizeNormal}"/>
                                    <TextBlock Name="txtPlatform" Margin="110,20,0,0" Text="{Binding Platform}"></TextBlock>
                                    <TextBlock Text="Release Date" FontWeight="Bold" Margin="110,46,0,0" Foreground="YellowGreen" FontSize="{StaticResource PhoneFontSizeNormal}"/>
                                    <TextBlock Name="txtReleaseDate" Margin="110,66,0,0" Text="{Binding ReleaseDate}"></TextBlock>
                                    <!--</StackPanel>-->
                                </Grid>
                                <Grid Grid.Row="2"></Grid>
                            </Grid>
                        </DataTemplate>
                    </Controls:RadJumpList.ItemTemplate>
                </Controls:RadJumpList>
            </Grid>
        </phone:PivotItem>

下面是我绑定我的DataContext到我的getgameslisttitems ObservableCollection在我的GameData类。当用户在文本框txtSearch中输入"Batman"并点击按钮时，imgBtnSearchGame_Click事件方法将被调用，然后它将把文本发送给我的GetGamesListData方法。

MainPage.cs:

GameData gd = new GameData();
public MainPage()
    {
        InitializeComponent();
        jlGameList.DataContext = gd.GetGamesListItems;
    }
 private void imgBtnSeachGame_Click(object sender, RoutedEventArgs e)
    {
        if (!string.IsNullOrEmpty(txtSearch.Text))
        {
            gd.GetGamesListData(txtSearch.Text, "", "");
        }
    }

下面是我下载搜索游戏名称的XML格式数据的地方。例如，如果是"Batman"，它将找到并返回所有带有"Batman"的游戏。"BoxArtFrontThumb"属性是我为每个游戏存储所有图像的地方，并且使用异步，因为有时可能有相当多的图像需要下载和显示。

GameData.cs

public void GetGamesListData(string name, string platform, string genre)
    {
        var webClient = new WebClient();
        webClient.DownloadStringCompleted += GetGamesListRequestCompleted;
        webClient.DownloadStringAsync(new Uri("http://thegamesdb.net/api/GetGamesList.php?name=" + name));
    }
    private async void GetGamesListRequestCompleted(object sender, DownloadStringCompletedEventArgs e)
    {
        if (e.Error == null)
        {
            GetGamesListItems.Clear();
            var feedXml = XDocument.Parse(e.Result);
            var gameDataTasks = feedXml.Root.Descendants("Game").Select(
                async x => new GetGamesList
                {
                    ID = (int)x.Element("id"),
                    GameTitle = (string)x.Element("GameTitle"),
                    ReleaseDate = (string)x.Element("ReleaseDate") ?? "N/A",
                    Platform = (string)x.Element("Platform") ?? "N/A",
                    BoxArtFrontThumb = new Uri(await GetBoxArtFrontThumbAsync((int)x.Element("id")), UriKind.RelativeOrAbsolute),
                }).ToList();
            var gameData = await Task.WhenAll(gameDataTasks);
            foreach (var item in gameData)
            {
                GetGamesListItems.Add(item);
            }
        }
    }

下面是查找和存储游戏图像的地方。

public async Task<string> GetBoxArtFrontThumbAsync(int id)
    {
        var client = new HttpClient();
        var result = await client.GetStringAsync("http://thegamesdb.net/api/GetArt.php?id=" + id);
        var feedXml = XDocument.Parse(result);
        var gameData = feedXml.Root.Descendants("Images").Select(x => new GetArt
        {
            BoxArtFrontThumb = new Uri(GetBoxArtFrontThumb(x), UriKind.RelativeOrAbsolute),
        }).ToList();

        return gameData.Single().BoxArtFrontThumb.ToString();
    }
private static string GetBoxArtFrontThumb(XElement gameNode)
    {
        string data = "http://thegamesdb.net/banners/" + (string)gameNode.Descendants("boxart")
                               .FirstOrDefault(b => (string)b.Attribute("side") == "front");
        if (data == "http://thegamesdb.net/banners/")
        {
            data = "/NoImage.jpg";
        }
        return data;
    }

我真的希望我解释得足够好，希望有人能帮助我解决这个问题。谢谢。