静态INotifyPropertyChanged事件不起作用

问题描述：

我有这个Base class:

public abstract class WiresharkFile : BaseObservableObject, IDisposable
{
    private string _fileName;
    private int _packets;
    private int _packetsSent;

    public string FileName
    {
        get { return _fileName; }
        set { _fileName = value; }
    }

    public int Packets
    {
        get { return _packets; }
        set { _packets = value; }
    }

    public int PacketsSent
    {
        get { return _packetsSent; }
        set
        {
            _packetsSent = value;
            OnPropertyChanged();
        }
    }

    public void Dispose()
    {
        // Implemented insde inherit classes.
    }
}

BaseObservableObject:

public class BaseObservableObject : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        var handler = PropertyChanged;
        if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
    }

    protected virtual void OnPropertyChanged<T>(Expression<Func<T>> raiser)
    {
        var propName = ((MemberExpression)raiser.Body).Member.Name;
        OnPropertyChanged(propName);
    }

    protected bool Set<T>(ref T field, T value, [CallerMemberName] string name = null)
    {
        if (!EqualityComparer<T>.Default.Equals(field, value))
        {
            field = value;
            OnPropertyChanged(name);
            return true;
        }
        return false;
    }
}

我的收藏集:

public ObservableCollection<WiresharkFile> wiresharkFiles { get; set; }

因此，如您所见，我的Base class的每个继承类都具有此PacketsSent属性更改，因此在这种情况下，一切正常.

So as you can see avery inherit class from my Base class have this PacketsSent property change so in this case all works fine.

现在，我在WiresharkFile(基类)内还有另一个静态属性:

Now i have another static property inside WiresharkFile (base class):

private static volatile int _totalPacketsSent;

public static int TotalPacketsSent
{
    get { return _totalPacketsSent; }
    set
    {
        _totalPacketsSent = value;
        OnStaticPropertyChanged();
    }
}

因此在BaseObservableObject内部，我创建了该成员:

So inside BaseObservableObject i created this member:

public static event PropertyChangedEventHandler StaticPropertyChanged;

并且:

protected static void OnStaticPropertyChanged([CallerMemberName] string propertyName = null)
{
    var handler = StaticPropertyChanged;
    if (handler != null) handler(typeof(WiresharkFile), new PropertyChangedEventArgs(propertyName));
}

在XAML内部，我想更新我的Label:

And inside XAML i want to update my Label:

Content="{Binding Path=(my:WiresharkFile.TotalPacketsSent)}"

所以这不起作用，因此当前Label通过后面的代码更新. 我做错什么了吗?

So this is not working so currently this Label is updated via code behind. As i doing something wrong ?

答

必须在类WiresharkFile中声明静态属性更改事件(即，该类也声明了静态属性).如果在基类中声明，它将无法正常工作.

The static property changed event has to be declared in class WiresharkFile (i.e. the class that also declares the static property). It won't work if it is declared in a base class.

public class WiresharkFile : BaseObservableObject
{
    public static event PropertyChangedEventHandler StaticPropertyChanged;

    private static void OnStaticPropertyChanged(string propertyName)
    {
        var handler = StaticPropertyChanged;
        if (handler != null)
        {
            handler(null, new PropertyChangedEventArgs(propertyName));
        }
    }

    // static property here
}

静态INotifyPropertyChanged事件不起作用

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