Question

我有一个来自wpf工具包2的复选框。我无法获取所有选定的项目。我读到我应该使用SelectedItemsOverride来获取我所有选定的项目，但它似乎不起作用。我在TestClassSelected的setter中设置了一个断点但它永远不会被触发。任何想法？

<xctk:CheckListBox Name="MyCheckList"
                   ItemsSource="{Binding TestClassCollection}"
                   DisplayMemberPath="DisplayName"
                   SelectedItemsOverride="{Binding TestClassSelected}"  />

public IEnumerable<TestClass> TestClassCollection
{
    get { return _testClassCollection; }
    set
    {
        _testClassCollection = value;
        OnPropertyChanged("TestClassCollection");
    }
}

public List<TestClass> TestClassSelected
{
    get { return _testClassSelected; }
    set
    {
        _testClassSelected = value;
        OnPropertyChanged("TestClassSelected");
    }
}

public class TestClass
{
    public String FirstName { get; set; }
    public String LastName { get; set; }

    public String DisplayName { 
         get { return string.Format("{0} {1}", FirstName, LastName); } 
    }
}

这是我一直在使用的测试数据。

TestClassCollection = new List<TestClass>
{
    new TestClass {FirstName = "FIrstName", LastName = "LastName"},
    new TestClass {FirstName = "Brad", LastName = "Holder"},
    new TestClass {FirstName = "Sam", LastName = "Ryans"},
    new TestClass {FirstName = "Ryan", LastName = "Thomas"},
    new TestClass {FirstName = "Lee", LastName = "Rod"},
    new TestClass {FirstName = "Amanda", LastName = "Gustaf"},
    new TestClass {FirstName = "Chris", LastName = "Holems"},
    new TestClass {FirstName = "Doug", LastName = "Schnitzel"},
    new TestClass {FirstName = "Lisa", LastName = "Bull"},
    new TestClass {FirstName = "Fred", LastName = "Simpson"},
    new TestClass {FirstName = "Scott", LastName = "Rogers"}
};

Answer 1

尝试在绑定时添加Mode和UpdateSourceTrigger

<xctk:CheckListBox Name="MyCheckList"
                   ItemsSource="{Binding TestClassCollection}"
                   DisplayMemberPath="DisplayName"
                   SelectedItemsOverride="{Binding TestClassSelected, 
                          Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />

<强>更新我在Extended WPF Toolkit CodePlex site检查了封闭问题中的示例代码。尝试将TestClassSelected属性更改为ObservableCollection。（仍然保留上面描述的.xaml中的UpdateSourceTrigger）

public ObservableCollection<TestClass> TestClassSelected

Answer 2

我结合了先前的答案/评论，对我有用的是将SelectedItemsOverride绑定到ObservableCollection<T>，包括UpdateSourceTrigger=PropertyChanged，并将方法附加到ObservableCollection<T>事件CollectionChanged。

XAML：

<xctk:CheckListBox 
    ItemsSource="{Binding AllItems}"
    DisplayMemberPath="Display"
    ValueMemberPath="Value" 
    SelectedItemsOverride="{Binding Path=DataContext.SelectedItems, RelativeSource={RelativeSource FindAncestor, AncestorType=Window}, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}">
</xctk:CheckListBox>

ViewModel中的代码：

public IEnumerable<Item> AllItems { get; set; }

public ObservableCollection<Item> SelectedItems { get; set; }

public ViewModel()
{
    SelectedItems = new ObservableCollection<Item>();

    SelectedItems.CollectionChanged += SelectedItems_CollectionChanged;
}

private void SelectedItems_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
{
    // Handle collection changed event
}

Answer 3

我遇到了同样的问题，并通过分配属性的私有字段解决了

在您的示例中

private ObservableCollection<TestClass> _testClassSelected=new ObservableCollection<TestClass>();

WPF工具包CheckListBox SelectedItemsOverride不起作用

3 个答案: