我正在使用yfiles库，并处理一个名为 view . 要为此对象激活鼠标滚轮滚动，我必须在registerviewlisteners函数中添加一个侦听器。不过，我也想在我的课堂上得到通知 mouseWheelMoved 鼠标移动时的功能

public class MyClass extends MyBaseClass implements MouseWheelListener {

    Graph2DView view;  
    // ..... 

    @Override
    protected void registerViewListeners()   
    {  
         Graph2DViewMouseWheelScrollListener wheelListener = new Graph2DViewMouseWheelScrollListener();
         wheelListener.addToCanvas(view);

         // The two precedent instruction is equivalent to 
         // view.getCanvasComponent().addMouseWheelListener(this);
    }

    @Override
    public void mouseWheelMoved(MouseWheelEvent e) 
    {    
        // some work ...
    }  
}

问题：
如果我注册 view 对象通过 registerViewListeners ```
@Override
protected void registerViewListeners()
{
Graph2DViewMouseWheelScrollListener wheelListener = new Graph2DViewMouseWheelScrollListener();
wheelListener.addToCanvas(view);
}

我的 `mouseWheelMoved` 不再通知函数：

@Override
public void mouseWheelMoved(MouseWheelEvent e)
{
// not called
}