Question

我的活动中有一个RecyclerView。我可以以编程方式一次滚动我的RecyclerView项（例如轮播上的动画效果）吗？我在下面有一些代码，但我不知道如何产生效果。欢迎任何建议！

RandomProductAdapter randomProductAdapter = new RandomProductAdapter(this.mContext, randomProductList);
random_rv.setLayoutManager(new LinearLayoutManager(getContext(), LinearLayoutManager.HORIZONTAL, false));
random_rv.setAdapter(randomProductAdapter);

random_rv.smoothScrollToPosition(randomProductAdapter.getItemCount()-1);

Answer 1

尝试以下逻辑：

findViewById(R.id.iv_next).setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        int totalItemCount = recycler_list.getAdapter().getItemCount();
        if (totalItemCount <= 0) return;
        int lastVisibleItemIndex = layoutManager.findLastVisibleItemPosition();
        if (lastVisibleItemIndex >= totalItemCount) return;
        layoutManager.smoothScrollToPosition(rv_category_list, null, lastVisibleItemIndex + 1);
    }
});

Answer 2

尝试使用此代码段实现对我有用：

RecyclerView my_recycler_view= (RecyclerView) findViewById(R.id.my_recycler_view);
SnapHelper snapHelper = new PagerSnapHelper();
snapHelper.attachToRecyclerView(my_recycler_view);

享受编码活动的欢呼！

Answer 3

感谢您的意见。我尝试使用线程应用某些逻辑，但我的应用不断崩溃。所以我找到了解决方案here和here also

首先创建可运行的文件：

final int duration = 10;
final int pixelsToMove = 30;
private final Handler mHandler = new Handler(Looper.getMainLooper());
private final Runnable SCROLLING_RUNNABLE = new Runnable() {

    @Override
    public void run() {
        recyclerView.smoothScrollBy(pixelsToMove, 0);
        mHandler.postDelayed(this, duration);
    }
};

然后在setadapter（）到recyclerView之后使用以下命令：

recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            super.onScrolled(recyclerView, dx, dy);
            int lastItem = layoutManager.findLastCompletelyVisibleItemPosition();
            if(lastItem == layoutManager.getItemCount()-1){
                mHandler.removeCallbacks(SCROLLING_RUNNABLE);
                Handler postHandler = new Handler();
                postHandler.postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        recyclerView.setAdapter(null);
                        recyclerView.setAdapter(madapter);
                        mHandler.postDelayed(SCROLLING_RUNNABLE, 2000);
                    }
                }, 2000);
            }
        }
    });
    mHandler.postDelayed(SCROLLING_RUNNABLE, 2000);

Answer 4

This 此处给出的答案非常有效。我已经使用了很多次，并没有出现错误。既简单又轻松。

final int time = 4000; // it's the delay time for sliding between items in recyclerview
final Adapter adapter = new Adapter(dataItems);
recyclerView.setAdapter(adapter);

final LinearLayoutManager linearLayoutManager = new LinearLayoutManager(rootView.getContext(), LinearLayoutManager.HORIZONTAL, false);
recyclerView.setLayoutManager(linearLayoutManager);

//The LinearSnapHelper will snap the center of the target child view to the center of the attached RecyclerView , it's optional if you want , you can use it
final LinearSnapHelper linearSnapHelper = new LinearSnapHelper();
linearSnapHelper.attachToRecyclerView(recyclerView); 

final Timer timer = new Timer();
timer.schedule(new TimerTask() {

    @Override
    public void run() {

        if (linearLayoutManager.findLastCompletelyVisibleItemPosition() < (adapter.getItemCount() - 1)) {
            linearLayoutManager.smoothScrollToPosition(recyclerView, new RecyclerView.State(), linearLayoutManager.findLastCompletelyVisibleItemPosition() + 1);
        }

        else if (linearLayoutManager.findLastCompletelyVisibleItemPosition() == (adapter.getItemCount() - 1)) {
            linearLayoutManager.smoothScrollToPosition(recyclerView, new RecyclerView.State(), 0);
        }
    }
}, 0, time);

RecyclerView自动滚动项目一项

4 个答案: