Question

我有一个将ObservableCollection绑定到LongListSelector的问题，我不知道如何解决这个问题。我有两个支点项目，第二个我希望有最喜欢的银行列表。当我点击“add_to_favourites”按钮时，两个银行（在第一个枢轴项目的listPicker中选择）应该添加到ObservableCollection并且它们会执行，但它们不会在UI中显示。

LongListSelector的XAML是：

</phone:PivotItem>
        <!--Pivot item two-->
        <phone:PivotItem  Header="Ulubione" Margin="10,0,10,7">
            <phone:LongListSelector x:Name ="FavouritesLongList" HorizontalAlignment="Left" Height="531" VerticalAlignment="Top" Width="456" Margin="-251,647,0,-647" LayoutMode="List" IsGroupingEnabled="False" SelectionChanged="Lista_Ulubione_SelectionChanged">
                <phone:LongListSelector.ItemTemplate>
                    <DataTemplate>
                        <TextBlock FontSize="35">
                            <Run Text="{Binding name1}"></Run>
                            <Run Text=" >> "></Run>
                            <Run Text="{Binding name2}"></Run>
                        </TextBlock>
                    </DataTemplate>
                </phone:LongListSelector.ItemTemplate>
            </phone:LongListSelector>
            <!--Double line list no text wrapping-->
        </phone:PivotItem>
    </phone:Pivot>

现在看看我的ObservableCollection：

public partial class MainPage : PhoneApplicationPage
{
    public List<Bank> list = new List<Bank>();
    private ObservableCollection<Ulubione> favourites = new ObservableCollection<Ulubione>();

    Wynik wy = new Wynik();
    // Constructor
    public MainPage()
    {
        InitializeComponent();
        zak.DataContext = wy;//TextBlocks DataContext
        ban1.DataContext = wy;
        ban2.DataContext = wy;
        zle.DataContext = wy;
        czas.DataContext = wy;

        DataContext = App.ViewModel;
        this.Banki1.ItemsSource = list;//Item sources for ListPicker
        this.Banki2.ItemsSource = list;}

点击我的add_to_favourites按钮：

private void addToFavourites(object sender, EventArgs e)
    {
        int b1 = this.Bank1.SelectedIndex;//ListPicker selected index of Bank1
        int b2 = this.Bank2.SelectedIndex;//ListPicker selected index of Bank2
        String n1 = list[this.Banki1.SelectedIndex].name;//Name od Bank1 from list of banks
        String n2 = list[this.Banki2.SelectedIndex].name;/Name od Bank2 from list of banks
        Ulubione fav = new Ulubione(b1, b2, n1, n2);

        bool ifCanAdd = true;
        foreach (Ulubione itm in favourites)
        {
            if (itm.index1 == b1 && itm.index2 == b2)
            {
                MessageBox.Show("This banks are already in favourites");
                ifCanAdd = false;
            }
        }
        if (ifCanAdd == true)
        {
            favourites.Add(fav);
            MessageBox.Show("Added to favourites");
            FavouritesLongList.ItemsSource = favourites;
        }
    }

请帮助我如何将此ObservableCollection绑定到LongListSelector，并在每次向集合添加内容时更新UI。

Answer 1

问题在于您在LLS中设置的保证金 - 保证金=“ - 251,647,0，-647”。这就是为什么你可能看不到任何东西。祝愿和编码愉快。

如何将ObservableCollection绑定到LongListSelector？

1 个答案: