Question

我想将具有属性“ID”，“描述”和“IsSelected”的项目列表绑定到组合框。显示值使用DisplayMemberPath设置为“描述”，工作正常。但是我希望在选择该项目时设置'IsSelected'属性。我已经尝试将SelectedValuePath和SelectedValue设置为'IsSelected'，但它不起作用。

Answer 1

最简单的解决方案可能是跟踪视图模型中的所选项目，并通过向ComboBox添加双向绑定使其与SelectedItem保持同步。当视图模型属性更改时，更新新选项和先前选择的IsSelected属性。

Answer 2

试试这个

    <ComboBox Width="120" Height="35">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <ComboBoxItem IsSelected="{Binding IsSelected}"/>
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>

Answer 3

没有什么比重新回答一个已有五年历史的问题了……我不同意 Mike ，因为ComboBox可以为您提供SelectedValue的IsSelected状态，因此您应该跟踪这两个状态。 Matrix 在右边，但是您不能将IsSelected与DisplayMemberPath一起使用。

通过下面的代码，我的Fruits Selected属性绑定到IsSelected。

查看代码

<ComboBox ItemsSource="{Binding Fruit}"
          SelectedValue="{Binding SelectedFruitViewModel}" 
          DisplayMemberPath="Name">
    <ComboBox.ItemContainerStyle>
        <Style TargetType="ComboBoxItem">
            <Setter Property="IsSelected" Value="{Binding Selected}" />
        </Style>
    </ComboBox.ItemContainerStyle>
</ComboBox>

MainWindowViewModel

public class MainWindowViewModel : BaseViewModel
{
    private FruitViewModel _selectedFruitViewModel;

    public MainWindowViewModel()
    {
        this.Fruit = new ObservableCollection<FruitViewModel>
        {
            new FruitViewModel { Name = "Pineapple", Selected = false },
            new FruitViewModel { Name = "Apple", Selected = false },
            new FruitViewModel { Name = "Orange", Selected = false },
            new FruitViewModel { Name = "Kiwi", Selected = false }
        };
    }

    public ObservableCollection<FruitViewModel> Fruit { get; }

    public FruitViewModel SelectedFruitViewModel
    {
        get => _selectedFruitViewModel;
        set => SetProperty(ref _selectedFruitViewModel, value);
    }
}

FruitViewModel

public class FruitViewModel : BaseViewModel
{
    private bool _selected;
    private string _name;

    public bool Selected
    {
        get => _selected;
        set => SetProperty(ref _selected, value);
    }

    public string Name
    {
        get => _name;
        set => SetProperty(ref _name, value);
    }
}

BaseViewModel

public class BaseViewModel : INotifyPropertyChanged 
{
    public virtual event PropertyChangedEventHandler PropertyChanged;

    protected virtual bool SetProperty<T>(ref T storage, 
                                          T value, 
                                          [CallerMemberName] string propertyName = null)
    {
        if (EqualityComparer<T>.Default.Equals(storage, value))
        {
            return false;
        }

        storage = value;

        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));

        return true;
    } 
}

wpf combobox - 绑定自定义的isselected属性

3 个答案: