类必须被声明为抽象或？

Question

我是android的新手.我一直使用代码片段来创建我的应用程序.所以我在这里复制了材料风格的抽屉.

现在我在这部分代码中面临一个问题:

static class RecyclerTouchListener implements RecyclerView.OnItemTouchListener {

    private GestureDetector gestureDetector;
    private ClickListener clickListener;

    public RecyclerTouchListener(Context context, final RecyclerView recyclerView, final ClickListener clickListener) {
        this.clickListener = clickListener;
        gestureDetector = new GestureDetector(context, new GestureDetector.SimpleOnGestureListener() {
            @Override
            public boolean onSingleTapUp(MotionEvent e) {
                return true;
            }

            @Override
            public void onLongPress(MotionEvent e) {
                View child = recyclerView.findChildViewUnder(e.getX(), e.getY());
                if (child != null && clickListener != null) {
                    clickListener.onLongClick(child, recyclerView.getChildPosition(child));
                }
            }
        });
    }

    @Override
    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {

        View child = rv.findChildViewUnder(e.getX(), e.getY());
        if (child != null && clickListener != null && gestureDetector.onTouchEvent(e)) {
            clickListener.onClick(child, rv.getChildPosition(child));
        }
        return false;
    }

    @Override
    public void onTouchEvent(RecyclerView rv, MotionEvent e) {
    }
}

在这个片段中,它给出了错误.我可以给出错误的图像

我试图使类抽象,但然后它干扰oncreate包代码.任何帮助,将不胜感激

Answer 1

此消息告诉您,RecyclerView.OnItemTouchListener(这是一个接口)定义了一个名为的方法onRequestDisallowInterceptTouchEvent(boolean).这个方法需要由实现OnItemTouchListener接口的每个类实现.

所以只需添加一个空体...

@Override
public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
}

...并查看Java语言中的接口:https: //docs.oracle.com/javase/tutorial/java/concepts/interface.html