WPF 组合框 在属性更改事件时未更新

Question

我的 WPF 应用程序中有一个自定义组合框，并且在初始启动后更新我的项源时，组合框未更新。itemsSource 是一个自定义的可观察词典。我已经在我的属性上实现了INotifyPropertyChanged与我的可观察词典，但它不会更新。我已经搜索了每个WPF属性更改事件，该事件在堆栈溢出上不起作用，我正在寻找一些帮助。

自定义组合框代码：

<controls:MultiSelectComboBox Width="100" Height="30" Padding="0 10 0 0" Grid.Row="0" Grid.Column="1"

    ItemsSource="{Binding Mode=TwoWay,             

                  UpdateSourceTrigger=PropertyChanged,                                                    

                  ValidatesOnDataErrors=True, 

                  Path=DataContext.OptionTeamMembersDictionary, 

                  BindsDirectlyToSource=True,                                                    

                  RelativeSource={RelativeSource AncestorType={x:Type UserControl},Mode=FindAncestor}}"

    SelectedItems="{Binding SelectedOptionTeamMembersDictionary, Mode=TwoWay}"

    x:Name="TeamMemberDisplay" 

    ToolTip="{Binding Path=Text, RelativeSource={RelativeSource Self}}"/>

属性和私有变量：

private ObservableDictionary<string, object> _optionTeamMembersDictionary;

private ObservableDictionary<string, object> _selectedOptionTeamMembersDictionary;

public ObservableDictionary<string, object> OptionTeamMembersDictionary

{

    get

    {

        return _optionTeamMembersDictionary;

    }

    set

    {

        _optionTeamMembersDictionary = value;

        OnPropertyChanged("OptionTeamMembersDictionary");

    }

}

public ObservableDictionary<string, object> SelectedOptionTeamMembersDictionary

{

    get

    {

        return _selectedOptionTeamMembersDictionary;

    }

    set

    {

        _selectedOptionTeamMembersDictionary = value;

        OnPropertyChanged("SelectedOptionTeamMembersDictionary");

    }

}

我使用一个按钮来触发数据库拉取，该拉取将每行引导到一个对象中，然后在返回多行数据时填充选项TeamMemberDictionary。

当数据加载到我的构造函数中时，上述所有内容都有效，但是当它在启动后加载时，我的组合框不会显示集合中的新数据。

Answer 1

经过多次故障排除，我能够找出答案。onItemsSourceChanged 在实例化控件后未触发，因此在应用程序初始启动后从未进行过更新。我将多功能组合盒上的OnItemsSourceChanged函数编辑到下面，以便它可以在更改的事件上触发，并且它现在按预期工作。private static void OnItemsSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; MultiSelectComboBox control = (MultiSelectComboBox)d;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var action = new NotifyCollectionChangedEventHandler(&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; (o, args) =>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; MultiSelectComboBox c = (MultiSelectComboBox)d;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; c?.DisplayInControl();&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; });&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (e.OldValue != null)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var sourceCollection = (ObservableDictionary<string, object>)e.OldValue;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; sourceCollection.CollectionChanged -= action;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (e.NewValue != null)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; var sourceCollection = (ObservableDictionary<string, object>)e.NewValue;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; sourceCollection.CollectionChanged += action;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; control.DisplayInControl();&nbsp; &nbsp; &nbsp; &nbsp; }