GridView 未加载数据

Question

在点击/单击页面上另一个 GridView 的 TextBlock 后，我正在尝试将数据加载到 GridView 中。包含 TextBlocks 列表的第一个 GridView 正确加载。

这是我的两个 GridView 的 XAML 代码，我的绑定似乎是正确的：

   <GridView x:Name="CourseNoGridView" Margin="50,50,0,0" Grid.Row="1" VerticalAlignment="Top" Height="568" ItemsSource="{Binding Distinct_CourseNo}" SelectionMode="Single" Padding="0,0,0,10" HorizontalAlignment="Left" Width="525" SelectionChanged="CourseNoGridView_SelectionChanged">
        <GridView.ItemTemplate>
            <DataTemplate>
                <Border BorderBrush="White">
                    <TextBlock x:Name="CourseNoTextBlock" Text="{Binding CourseNo}" TextWrapping="NoWrap" FontSize="24" Width="200" Height="Auto" Padding="10" Tapped="CourseNoTextBlock_Tapped"/>
                </Border>
            </DataTemplate>
        </GridView.ItemTemplate>
    </GridView>
    <GridView x:Name="SectionsGridView" Margin="580,50,0,0" Grid.Row="1" VerticalAlignment="Top" Height="568" ItemsSource="{Binding Clicked_CourseNo_Sections}" SelectionMode="Single" Padding="0,0,0,10" HorizontalAlignment="Left" Width="776" SelectionChanged="CourseNoGridView_SelectionChanged">
        <GridView.ItemTemplate>
            <DataTemplate>
                <Border BorderBrush="White">
                    <TextBlock x:Name="SectionTextBlock" Text="{Binding Get_Section}" TextWrapping="NoWrap" FontSize="24" Width="200" Height="Auto" Padding="10"/>
                </Border>
            </DataTemplate>
        </GridView.ItemTemplate>
    </GridView>

这是我在第一个 GridView 中处理单击/轻敲项目的代码：

private void CourseNoGridView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    clickedSection = (Sections)e.AddedItems[0];
}

private void CourseNoTextBlock_Tapped(object sender, TappedRoutedEventArgs e)
{
    this.Clicked_CourseNo_Sections = (from s in Roster_Sections
                                      where s.CourseNo.Equals(clickedSection.CourseNo)
                                      select s).ToList();
}

Answer 1

您想要做的是使用 ObservableCollection 并将您的网格视图绑定到此。然后在“Tapped”事件处理程序中清除此集合中的现有项目并添加新项目。

类似这样的：

private readonly ObservableCollection<Sections> currentSections = new ObservableCollection<Sections>();

//This is what we bind to
public ObservableCollection<Sections> CurrentSections { get { return currentSections; } }

private void CourseNoGridView_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
  clickedSection = (Sections)e.AddedItems[0];
}

private void CourseNoTextBlock_Tapped(object sender, TappedRoutedEventArgs e)
{
  var courseSections = (from s in Roster_Sections
                  where s.CourseNo.Equals(clickedSection.CourseNo)
                  select s);

  CurrentSections.Clear();
  CurrentSections.AddRange(courseSections);
}

这里有一些文档：

http://msdn.microsoft.com/en-us/library/windows/apps/hh758320.aspx

Answer 2

似乎在下面添加最后一行代码可以解决问题。

 private void CourseNoTextBlock_Tapped(object sender, TappedRoutedEventArgs e)
        {
            this.Clicked_CourseNo_Sections = (from s in Roster_Sections
                                              where s.CourseNo.Equals(clickedSection.CourseNo)
                                              select s).ToList();

            SectionsGridView.ItemsSource = Clicked_CourseNo_Sections;
        }