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当 UI 未更新为更改绑定到控件属性的变量时，我遇到了问题。帮助我理解为什么。

1）我有一个继承自 UserControl 和 InotifyPropertyChanged 的​​类

public class BindableControl:UserControl, INotifyPropertyChanged
    {
        #region Data

        private static readonly Dictionary<string, PropertyChangedEventArgs> eventArgCache;
        private const string ERROR_MSG = "{0} is not a public property of {1}";

        #endregion // Data

        #region Constructors

        static BindableControl()
        {
            eventArgCache = new Dictionary<string, PropertyChangedEventArgs>();
        }

        protected BindableControl()
        {
        }

        #endregion // Constructors

        #region Public Members

        /// <summary>
        /// Raised when a public property of this object is set.
        /// </summary>
        [field: NonSerialized]
        public event PropertyChangedEventHandler PropertyChanged;

        /// <summary>
        /// Returns an instance of PropertyChangedEventArgs for 
        /// the specified property name.
        /// </summary>
        /// <param name="propertyName">
        /// The name of the property to create event args for.
        /// </param>        
        public static PropertyChangedEventArgs
            GetPropertyChangedEventArgs(string propertyName)
        {
            if (String.IsNullOrEmpty(propertyName))
                throw new ArgumentException(
                    "propertyName cannot be null or empty.");

            PropertyChangedEventArgs args;

            // Get the event args from the cache, creating them
            // and adding to the cache if necessary.
            lock (typeof(BindableObject))
            {
                bool isCached = eventArgCache.ContainsKey(propertyName);
                if (!isCached)
                {
                    eventArgCache.Add(
                        propertyName,
                        new PropertyChangedEventArgs(propertyName));
                }

                args = eventArgCache[propertyName];
            }

            return args;
        }

        #endregion // Public Members

        #region Protected Members

        /// <summary>
        /// Derived classes can override this method to
        /// execute logic after a property is set. The 
        /// base implementation does nothing.
        /// </summary>
        /// <param name="propertyName">
        /// The property which was changed.
        /// </param>
        protected virtual void AfterPropertyChanged(string propertyName)
        {
        }

        /// <summary>
        /// Attempts to raise the PropertyChanged event, and 
        /// invokes the virtual AfterPropertyChanged method, 
        /// regardless of whether the event was raised or not.
        /// </summary>
        /// <param name="propertyName">
        /// The property which was changed.
        /// </param>
        protected void RaisePropertyChanged([CallerMemberName] string propertyName = "")
        {
            this.VerifyProperty(propertyName);

            PropertyChangedEventHandler handler = this.PropertyChanged;
            if (handler != null)
            {
                // Get the cached event args.
                PropertyChangedEventArgs args =
                    GetPropertyChangedEventArgs(propertyName);

                // Raise the PropertyChanged event.
                handler(this, args);
            }

            this.AfterPropertyChanged(propertyName);
        }
        #endregion

        #region Private Helpers

        [Conditional("DEBUG")]
        private void VerifyProperty(string propertyName)
        {
            Type type = this.GetType();

            // Look for a public property with the specified name.
            PropertyInfo propInfo = type.GetProperty(propertyName);

            if (propInfo == null)
            {
                // The property could not be found,
                // so alert the developer of the problem.

                string msg = string.Format(
                    ERROR_MSG,
                    propertyName,
                    type.FullName);

                Debug.Fail(msg);
            }
        }
        #endregion
    }

2）然后我有另一个类，它们中的每一个都像这样从 BindableControl 继承

public class CameraLocalization : BindableControl
    {
        public CameraLocalization()
        {
            headers = new CameraHeaders();
            toolTips = new CameraToolTips();

            SetRuLocal();
            //SetEnLocal();
        }

        private Language lang = SettingsManager.Language.ru_RU;
        private CameraHeaders headers;
        private CameraToolTips toolTips;

        public Language Lang
        {
            get { return lang; }
            set
            {
                lang = value;
                SetLocal();
                RaisePropertyChanged();

            }
        }

3）在 XAML 中，我将此类链接为用户控件并像这样进行绑定：

    xmlns:language ="clr-namespace:SettingsManager.Localization.Camera"
     <Grid>
           <language:CameraLocalization x:Name="Localization"></language:CameraLocalization>
<GroupBox Header="{Binding ElementName=Localization, Path=Headers.PositionGroupHeader, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}"

4）从另一个页面我尝试更改语言：

    xmlns:language ="clr-namespace:SettingsManager.Localization.Camera"
<Grid Width="Auto">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition/>
        </Grid.RowDefinitions>
        <StackPanel Width="Auto" Margin="0,0,0,5">
            <language:CameraLocalization x:Name="Localization"></language:CameraLocalization>
<ComboBox ItemsSource="{Binding Source={StaticResource Language}}" Width="70" HorizontalAlignment="Left"
                                              SelectedValue="{Binding ElementName=Localization, Path=Lang, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"></ComboBox>

什么也没有发生。在调试模式下，我看到属性值发生变化，但它们不会在 UI 上更新。这里有什么问题？谁知道？

4

1 回答 1

0

您的属性不应在 UI 元素 ( UserControl) 中声明，并且这些不应实现INotifyPropertyChanged。您必须使用MVVM Pattern将 UI 与数据/逻辑分开。

您应该创建一个适当的 ViewModel 并将您的属性和属性更改通知放在那里。

于 2013-06-09T15:30:31.207 回答