来自另一个列表视图的 WPF ListView 绑定

Question

首先查看我的数据库 - LINK 和我的 ListView Binding

在第一个 ListView 中，我从表“TestSubjectsNames”中显示了“TestSubjectName”，当我从表“Tests”中选择要在第二个 ListView“TestName”中显示的项目时，其中“TestSBJNameID”==“ID”来自第一个 ListView 中的选定项目.

这是我关于第二个 ListView 的代码的一部分，但它不正确。

    private IEnumerable<Tests> testsNames;

    public IEnumerable<Tests> TestsNames
    {
        get
        {
            if (this.testsNames== null)
            {
                this.testsNames= BindingData.GetAllTestsNames;
            }
            return this.testsNames;
        }
    }

    public static IEnumerable<Tests> GetAllTestsNames
    {
        get
        {
            return new Model().TestsNames.Where(t => t.ID == FIRST-LISTVIEW-SELECTED-INDEX).Select(c => new Tests 
            {
                testNameID = c.ID,
                testName = c.TestsNames                   
            });
        }            
    }

如果有人有任何其他解决方案，如何从第一个 ListView 中选择到在第二个 ListView 中显示项目，请告诉我。

Answer 1

我认为有很多方法可以做你想做的事，这就是我会做的：

在代码隐藏中

public class TestWindow
{

    // A collection of SubjectNames to bind with the first listview
    private ObservableCollection<TestsSubjectsNames> _subjectNames;
    public ObservableCollection<TestsSubjectsNames> SubjectNames
    {
        get { return _subjectNames; }
        set
        {
           _subjectNames = value;
           NotifyPropertyChanged("SubjectNames");
        }
    }

    // A collection of Test for the second listview
    private ObservableCollection<Tests> _testNames;
    public ObservableCollection<Tests> TestNames
    {
        get { return _testNames; }
        set
        {
           _testNames= value;
           NotifyPropertyChanged("TestNames");
        }
    }

    // The current selected TestsSubjectsNames in first listview
    private TestsSubjectsNames _selectedSubjectNames;
    public TestsSubjectsNames SelectedSubjectNames
    {
        get { return _selectedSubjectNames; }
        set
        {
           _selectedSubjectNames= value;
           // Call this function in the setter
           // Will change the Collection binded to the second listview
           OnSelectedSubjectNameChanged(value);
           NotifyPropertyChanged("SelectedSubjectNames");
        }
    }

    public TestWindow()
    {
        // Initialization and set datacontext
        InitializeComponent();
        DataContext = this;

        // Initialize the suject name list for the first listview
        SubjectNames = GetAllSubjectNames();

        // Second listview empty until we select something in the first list
        // so initialize it empty
        TestNames = new ObservableCollection<Tests>();
    }

    // Will be called everyTime the selectedItem in the first listview changes
    private void OnSelectedSubjectNameChanged(TestsSubjectsNames subjectName)
    {
          // Get The list of Tests with the selected subjectName ID
          // and put the result in the observable collection
          TestNames = new ObservableCollection<Tests>(GetAllTestsNames(subjectName.ID))
    }
}

现在您只需在 XAML 中正确绑定

第一个列表视图：

 // SelectedItem attribute very important
 <ListView  
      ItemsSource="{Binding SubjectNames}" 
      SelectedItem="{Binding SelectedSubjectNames}" >
    <ListView.ItemTemplate>
        <DataTemplate>
            <WrapPanel>
                // show a textblock with the TestsSubjectName property
                // of TestsSubjectsNames class 
                <TextBlock Text="{Binding TestsSubjectName}" />
            </WrapPanel>
        </DataTemplate>
    </ListView.ItemTemplate>
 </ListView>

第二个列表视图

 <ListView ItemsSource="{Binding TestNames}" >
    <ListView.ItemTemplate>
        <DataTemplate>
            <WrapPanel>
                // show a textblock with the TestName property
                // of Tests class 
                <TextBlock Text="{Binding TestName}" />
            </WrapPanel>
        </DataTemplate>
    </ListView.ItemTemplate>
 </ListView>

在第一个 ListView 中，我们将 SelectedItem 与 SelectedSubjectNames 绑定，并且每次设置 SelectedSubjectNames 时，我们调用函数 OnSelectedSubjectNameChanged 来更改 TestNames 集合。

由于TestNames在第二个ListView中被绑定为itemsSource，所以每次选择不同的主题名时，第二个listview中都会出现测试名称列表。

希望它足够清楚并回答了您的问题。