Question

我试图从包含其中2个其他列表的列表中绑定属性，但由于某种原因，它不会在我的数据网格上显示任何内容。

正如您在下面看到的，我创建了一个observableCollection，当我调试时，该列表具有所有必需的属性（我试图在XAML绑定部分中添加的属性），但由于某种原因它不起作用。

初始化数据网格的类

        private CategoryServiceClient quizClient = new CategoryServiceClient();
        private IList<Category> quizList;

        public QuizWindow()
        {
            InitializeComponent();
            LoadUserData();
        }

        private void LoadUserData()
        {
            // The GetCategoriesQuestionAnswers method has a list of categories with a 
            // list of questions and a list of answers
            quizList = new ObservableCollection<Category>(quizClient.GetCategoriesQuestionsAnswers());
            try
            {
                quizDatagrid.ItemsSource = quizList;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Error", MessageBoxButton.OK, MessageBoxImage.Error);
                throw;

            }
        }

XAML

 <DataGrid x:Name="quizDatagrid" CanUserAddRows="False" Margin="10,90,0,10" ClipboardCopyMode="None" AutoGenerateColumns="False" HorizontalAlignment="Left" Width="698">
        <DataGrid.Columns>
            <DataGridTextColumn Binding="{Binding id}" Header="Category ID" />
            <DataGridTextColumn Binding="{Binding name}" Header="Category Name" />
            <DataGridTextColumn Binding="{Binding category.question.id}" Header="Question ID" />
            <DataGridTextColumn Binding="{Binding category.question.description}" Header="Question Description" />
            <DataGridTextColumn Binding="{Binding category.question.answer.id}" Header="Answer ID" />
            <DataGridTextColumn Binding="{Binding category.question.answer.description}" Header="Answer Description" />
            <DataGridTextColumn Binding="{Binding category.question.answer.isCorrect}" Header="Is Correct" />
            <DataGridTextColumn Binding="{Binding category.question.answer.pointAmount}" Header="Point Amount" />
        </DataGrid.Columns>
    </DataGrid>

这是类别类

public class Category
{
    [DataMember]
    public int id { get; set; }
    [DataMember]
    public string name { get; set; }
    [DataMember]
    public int amount { get; set; }
    [DataMember]
    public Quiz quiz { get; set; }
    [DataMember]
    public List<Question> question { get; set; }

    public Category()
    { 
        question = new List<Question>();
    }
}

这是我的问题类

[DataContract(IsReference = true)]
public class Question
{

    [DataMember]
    public int id { get; set; }
    [DataMember]
    public string description { get; set; }
    [DataMember]
    public Category category { get; set; }
    [DataMember]
    public bool isAnswered { get; set; }
    [DataMember]
    public List<Answer> Answers { get; set; }

    public Question()
    {
        Answers = new List<Answer>();
    }
}

Answer 1

DataGrid只会为其ItemsSource中的每个项添加一行（在本例中为ObservableCollection），即每个 Category 对象获取一行，而不是每个Question对象中的一行一个类别。

它不是等级的。如果要在同一个DataGrid中显示属于特定类别的所有问题，可以使用包含嵌套DataGrid的DataGridTemplateColumn：

        <DataGrid x:Name="quizDatagrid" CanUserAddRows="False" Margin="10,90,0,10" 
              ClipboardCopyMode="None" AutoGenerateColumns="False" HorizontalAlignment="Left" Width="698">
        <DataGrid.Columns>
            <DataGridTextColumn Binding="{Binding id}" Header="Category ID" />
            <DataGridTextColumn Binding="{Binding name}" Header="Category Name" />
            <DataGridTemplateColumn>
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <DataGrid ItemsSource="{Binding question}" AutoGenerateColumns="False">
                            <DataGrid.Columns>
                                <DataGridTextColumn Binding="{Binding id}" Header="Question ID" />
                                <DataGridTextColumn Binding="{Binding description}" Header="Question Description" />
                                <DataGridTextColumn Binding="{Binding answer.id}" Header="Answer ID" />
                                <DataGridTextColumn Binding="{Binding answer.description}" Header="Answer Description" />
                                <DataGridTextColumn Binding="{Binding answer.isCorrect}" Header="Is Correct" />
                                <DataGridTextColumn Binding="{Binding answer.pointAmount}" Header="Point Amount" />
                            </DataGrid.Columns>
                        </DataGrid>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
        </DataGrid.Columns>
    </DataGrid>

您可以通过绑定到每个Category对象中问题列表中的第一个索引，在同一个顶级DataGrid中显示类别的第一个问题：

<DataGrid x:Name="quizDatagrid" CanUserAddRows="False" Margin="10,90,0,10" ClipboardCopyMode="None" AutoGenerateColumns="False" HorizontalAlignment="Left" Width="698">
    <DataGrid.Columns>
        <DataGridTextColumn Binding="{Binding id}" Header="Category ID" />
        <DataGridTextColumn Binding="{Binding name}" Header="Category Name" />
        <DataGridTextColumn Binding="{Binding question[0].id}" Header="Question ID" />
        <DataGridTextColumn Binding="{Binding question[0].description}" Header="Question Description" />
        <DataGridTextColumn Binding="{Binding question[0].answer.id}" Header="Answer ID" />
        <DataGridTextColumn Binding="{Binding question[0].answer.description}" Header="Answer Description" />
        <DataGridTextColumn Binding="{Binding question[0].answer.isCorrect}" Header="Is Correct" />
        <DataGridTextColumn Binding="{Binding question[0].answer.pointAmount}" Header="Point Amount" />
    </DataGrid.Columns>
</DataGrid>

编辑：您将DataGrid的ItemsSource设置为ObservableCollection。每个类别都有一系列问题。每个问题都有一系列答案。 DataGrid将仅为每个类别呈现一行。您只能在此级别上显示单个问题和单个答案：

<DataGridTextColumn Binding="{Binding question[0].id}" Header="Question ID" />
<DataGridTextColumn Binding="{Binding question[0].description}" Header="Question Description" />
<DataGridTextColumn Binding="{Binding question[0].Answers[0].id}" Header="Answer ID" />
<DataGridTextColumn Binding="{Binding question[0].Answers[0].description}" Header="Answer Description

Datagrid中列表列表的绑定属性

1 个答案: