Question

我有以下ComboBox从枚举中获取populat：

<ComboBox Name="cmbProductStatus" ItemsSource="{Binding Source={StaticResource statuses}}" 
                                                  SelectedItem="{Binding Path=Status}" />

请注意，DataContext在代码隐藏中设置。

它甚至不是双向绑定，我有一些Product.Status的默认值，但它永远不会被选中。

更新

我被要求输入我的Status属性的代码。

public class Product    {
    //some other propertties
    private ProductStatus _status = ProductStatus.NotYetShipped;
    public ProductStatus Status { get { return _status; } set { value = _status; } }
}

public enum ProductStatus { NotYetShipped, Shipped };

Answer 1

ComboBox绑定有点棘手。确保在分配DataContext时加载了itemssource，并且使用SelectedItem分配的项目与ItemsSource中的一个项目符合==关系。

Answer 2

您的状态属性必须通知其更改，并且您的Product类必须实现INotifyPropertyChanged接口。

这里有属性的MVVM Light代码片段; - ）

/// <summary>
        /// The <see cref="MyProperty" /> property's name.
        /// </summary>
        public const string MyPropertyPropertyName = "MyProperty";

        private bool _myProperty = false;

        /// <summary>
        /// Gets the MyProperty property.
        /// TODO Update documentation:
        /// Changes to that property's value raise the PropertyChanged event. 
        /// This property's value is broadcasted by the Messenger's default instance when it changes.
        /// </summary>
        public bool MyProperty
        {
            get
            {
                return _myProperty;
            }

            set
            {
                if (_myProperty == value)
                {
                    return;
                }

                var oldValue = _myProperty;
                _myProperty = value;

                // Remove one of the two calls below
                throw new NotImplementedException();

                // Update bindings, no broadcast
                RaisePropertyChanged(MyPropertyPropertyName);

                // Update bindings and broadcast change using GalaSoft.MvvmLight.Messenging
                RaisePropertyChanged(MyPropertyPropertyName, oldValue, value, true);
            }
        }

WPF ComboBox SelectedItem绑定不起作用

2 个答案: