我正在开发uwp，我有一个数据绑定的问题。我有一个listView，我用一个名为PlaylistLeftOption类的自定义面板元素填充。这个类继承了Panel类的属性，而Panel类的属性又继承了FrameworkElement类的属性及其方法，所以我有一个可用的SetBinding方法。现在我尝试绑定height值（它等于其他元素），因此我在其他extern单例类中创建了一个名为PerformanceItemHeight的静态属性。因为我需要动态地填充listview，所以我试图在构造函数中绑定值，但它不起作用。这是构造函数内部的代码：

public PlaylistLeftOption()
    {
        mainGrid.Background = new SolidColorBrush(Colors.Red);
        mainGrid.BorderBrush = new SolidColorBrush(Colors.Black);
        mainGrid.BorderThickness = new Thickness(0.5,0.25,0.5,0.25);

        WidthVal = 200;
        HeightVal = 50;

        var myBinding = new Binding();
        myBinding.Source = PerformanceLayout.Instance.PerformanceItemHeight;
        myBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
        myBinding.Mode = BindingMode.TwoWay;
        SetBinding(HeightValProperty, myBinding);

        Children.Add(mainGrid);
    }

这就是财产：

public static readonly DependencyProperty HeightValProperty = DependencyProperty.Register(
      "HeightVal",
      typeof(double),
      typeof(PlaylistLeftOption),
      new PropertyMetadata(50)
    );

    public double HeightVal
    {
        get => (double)GetValue(HeightValProperty);
        set
        {
            SetValue(HeightValProperty, value);
            Height = HeightVal;
            mainGrid.Height = HeightVal;
            globalSize.Height = HeightVal;
        }
    }

下面是PerformanceItemHeight的代码：

public event PropertyChangedEventHandler PropertyChanged;

    public void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        // Raise the PropertyChanged event, passing the name of the property whose value has changed.
        this.PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }

    private double _performanceItemHeight = 50;
    public double PerformanceItemHeight {
        get => _performanceItemHeight;
        set {
            _performanceItemHeight = value;
            this.OnPropertyChanged();
        }
    }

为什么通过xaml它的作品？我试着通过xaml在listview中添加PlaylistLeftOption项，没问题！谢谢