INotifyPropertyChanged没有更新UI(WPF)

Question

问题是ViewModel属性与控件属性的绑定无法正常工作.我检查了属性及其值的变化,但控件的可见性不会改变.知道这涉及到什么吗？或者我错过了什么？

视图模型:

class MainViewModel
{
    public LoginViewModel LoginViewModel { get; set; }
    Notifier notifier = new Notifier();

    public MainViewModel()
    {
        LoginViewModel = new LoginViewModel();
    }
    private Visibility mdiPanelVisibility=Visibility.Visible;
    public Visibility MDIPanelVisibility
    {
        get
        {
            return mdiPanelVisibility;
        }
        set
        {
            mdiPanelVisibility = value;
            NotifyPropertyChanged("MDIPanelVisibility");
        }
    }

    private RelayCommand showMDIPanelCommand;
    public RelayCommand ShowMDIPanelCommand
    {
        get
        {
            return showMDIPanelCommand ??
                (showMDIPanelCommand = new RelayCommand(obj =>
                {
                    MDIPanelVisibility = Visibility.Visible;
                }));
        }
    }

    private RelayCommand hideMDIPanelCommand;
    public RelayCommand HideMDIPanelCommand
    {
        get
        {
            return hideMDIPanelCommand ??
                (hideMDIPanelCommand = new RelayCommand(obj =>
                {
                    MDIPanelVisibility = Visibility.Hidden;
                }));
        }
    }
    private event PropertyChangedEventHandler PropertyChanged;

    public void NotifyPropertyChanged([CallerMemberName] String propertyName = "")
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

并查看:

<Border Visibility="{Binding MDIPanelVisibility}">
        <Border.InputBindings>
            <MouseBinding MouseAction="LeftClick" Command="{Binding HideMDIPanelCommand}"/>
        </Border.InputBindings>
    </Border>
    <ContentPresenter Width="Auto" Grid.RowSpan="2" Panel.ZIndex="1" VerticalAlignment="Center" Visibility="{Binding MDIPanelVisibility}">
        <ContentPresenter.Content>
            <local:MDIView/>
        </ContentPresenter.Content>
    </ContentPresenter>
    <Button Content="?????? ???????" FontSize="13" Command="{Binding ShowMDIPanelCommand}">
        <Button.Style>
            <Style TargetType="Button" BasedOn="{StaticResource aLogButton}"/>
        </Button.Style>
    </Button> 

Answer 1

本MainViewModel类需要继承INotifyPropertyChanged,你的类不,为了使绑定框架的行为时,视图的预期DataContext设定为MainViewModel实例.

更新类定义

public class MainViewModel: INotifyPropertyChanged {
    //...
}