WPF Listview綁定不適用於Dictionary

Question

我有一個WPF項目，在XAML文件中，我有一個listview並綁定到字典。 但是，每當我更改字典值的值時，它都不會綁定回UI。 誰能幫忙。

我的代碼示例如下所示。

.XAML文件：

<DockPanel Grid.Row="1" Grid.Column="0">
    <Border BorderBrush="SkyBlue" BorderThickness="1,1,1,1"></Border>
        <StackPanel>
                <ListView Margin="0" ScrollViewer.HorizontalScrollBarVisibility="Hidden" Name="lvAlphaKeys" BorderThickness="0" ItemsSource="{Binding AlphaKeys, Mode=TwoWay}"  >
                    <ListView.ItemTemplate>
                        <DataTemplate>
                            <WrapPanel>
                                <TextBlock Text="{Binding Key}" Width="30" FontWeight="Bold" />
                                <TextBlock Text="{Binding Value.DispalyName, Mode=TwoWay}" />
                            </WrapPanel>
                        </DataTemplate>
                    </ListView.ItemTemplate>
                    </ListView.ItemTemplate>
                </ListView>
        </StackPanel>
</DockPanel>

查看模型：

public class MyViewModel : INotifyPropertyChanged
 {
         public event PropertyChangedEventHandler PropertyChanged;
         private Dictionary<string, MyCommand> _AlphaKeys;

        public Dictionary<string, MyCommand> AlphaKeys
        {
            get { return _AlphaKeys; }
            set
            {
                _AlphaKeys = value;
                OnPropertyChanged(new PropertyChangedEventArgs("AlphaKeys"));
            }
        }
}

 public class  MyCommand
    {
        public string DispalyName { get; set; }
        public string DisplaySymbol { get; set; }
    }

.XaML.CS文件：

//Field declaration
        MyViewViewModel viewModel;

//Constructur
     viewModel = new MyViewViewModel();
     DataContext = viewModel;   


//Event
    viewModel.AlphaKeys[key].DispalyName = "new value";

如果我將itemsource設置為null，然后重新分配列表值的Itemsource，它將正常工作，否則將無法正常工作，有人可以幫忙嗎？ lvAlphaKeys.ItemSource = null; lvAlphaKeys..ItemSource = viewModel.AlphaKeys;

Answer 1

您為AlphaKeys設置了事件，如果集合發生了更改，它將引發一個事件，而不是其項目。

您必須為MyCommand設置INotifyPropertyChanged ，

 public class  MyCommand : INotifyPropertyChanged
    {
        private string _dispalyName ;
        public string DispalyName 
        {
            get { return _dispalyName ; }
            set
            {
                _dispalyName = value;
                NotifyOfPropertyChange("DispalyName");
            }
        }


        public event PropertyChangedEventHandler PropertyChanged;
        protected void NotifyOfPropertyChange(string name)
        {
            PropertyChangedEventHandler handler = PropertyChanged;

            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs(name));
            }
        }
    }