LazyVerticalLayoutConnector.java 文件源码

protected void attachScrollingEvents(ComponentConnector connector) {
    Widget widget = connector.getWidget();
    if(widget instanceof LazyScrollNotifier) {
        LazyScrollNotifier not = (LazyScrollNotifier) widget;
        scrollingElement = not.getLazyScrollingElement();
        not.addLazyScrollListener(this);
    } else if (widget instanceof VWindow) {
        final VWindow window = (VWindow)widget;
        scrollingElement = window.contentPanel.getElement();
        handlerRegistration = ((VWindow)widget).contentPanel.addScrollHandler(new ScrollHandler() {
            @Override
            public void onScroll(ScrollEvent event) {
                onLazyScroll(window.contentPanel.getElement());
            }
        });
    } else {
        LOGGER.severe("Failed to connect to scrolling events of " + connector.getClass().getName());
    }
}