Question

我遇到的问题是，当我更改TextBox布尔值ObservableCollection时，我的IsFoo不会隐藏也不可见。我不知道为什么会这样。我想念什么吗？

模型用于ObservableCollection`

public class FooModel: Model
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public bool IsFoo { get; set; }
        public string FooStr{ get; set; }
    }

模型在ViewModel和View之间使用

public class SomeModel: Model
    {
        public Model()
    {         
        FooModels= new ObservableCollection<FooModel>();
    }

    private ObservableCollection<FooModel> _fooModels;

    public ObservableCollection<FooModel> FooModels
      {
        get => _fooModels;
        set => SetProperty(ref _fooModels, value);
      } 
    }

查看

<ItemsControl FontWeight="Normal" ItemsSource="{Binding Model.FooModels}">
                    <ItemsControl.ItemTemplate>
                        <DataTemplate DataType="{x:Type models:FooModel}">
                            <DockPanel HorizontalAlignment="Left">
                                <CheckBox
                                    HorizontalAlignment="Right"
                                    Content="{Binding Name}"
                                    DockPanel.Dock="Left"
                                    IsChecked="{Binding IsFoo}" />

                                <TextBox
                                    DockPanel.Dock="Right"
                                    Style="{StaticResource SimpleTextBox}"
                                    Text="{Binding FooStr}"
                                    Visibility="{Binding IsFoo, Converter={StaticResource BooleanToVisibilityHideConverter}}" />
                            </DockPanel>
                        </DataTemplate>
                    </ItemsControl.ItemTemplate>

Answer 1

只要数据绑定的源属性设置为新值，就应该实现INotifyPropertyChanged并向UI发出更改通知：

public class FooModel : Model, INotifyPropertyChanged
{
    public int Id { get; set; }
    public string Name { get; set; }

    private bool _isFoo;
    public bool IsFoo
    {
        get { return _isFoo; }
        set { _isFoo = value; OnPropertyChanged(); }
    }

    public string FooStr { get; set; }

    public event PropertyChangedEventHandler PropertyChanged;
    protected void OnPropertyChanged([CallerMemberName] String propertyName = "")
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

WPF ItemsControl元素不会更改ObservableCollection值更改MVVM的可见性

1 个答案: