Android 自动滚动的RecyclerView，手动滑动和自动滑动无缝衔接，手动滑动时数据不重复

概要

做一个自动滑动的列表，用于展示聊天记录或者通知栏信息等，还是使用主流的RecyclerView来做。网上有很多案例，但当手动滑动时会一直无限循环，数据重复的出现，如果想要自动滑动时能无限循环，手动滑动时又能滑到底呢？本案例就解决这种手动滑动和自动滑动无缝衔接的问题。

思路

1、重写RecyclerView，通过scrollBy和postDelayed进行定时移动到达自动滑动目的

2、RecyclerView添加addOnScrollListener，进行手指按下滑动和抬起监听，用于判断是手动滑动还是自动滑动。

3、修改adapter的itemCount

4、接下来上代码

实现方案

1、重写 RecyclerView：

public class SocllRecyclerView extends RecyclerView {
    private Autoaaview autoview;
    private boolean running;
    private boolean canrun;

    private static final int Timea = 40;//控制滚动的速度，值越大速度越慢

    public SocllRecyclerView(@NonNull Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        autoview = new Autoaaview(this);
    }

    public SocllRecyclerView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }


    private class Autoaaview implements Runnable{
        WeakReference<SocllRecyclerView> myScrViewWeakReference;
        public Autoaaview(SocllRecyclerView myScrView) {
            myScrViewWeakReference = new WeakReference<>(myScrView);
        }

        @Override
        public void run() {
            SocllRecyclerView myScrView = myScrViewWeakReference.get();
            if (myScrView.canrun&&myScrView.running){
                myScrView.scrollBy(2,2);
                myScrView.postDelayed(myScrView.autoview,Timea);
            }
        }
    }
    //开始滚动
    public void start(){
        if (running)
            stop();
        running = true;
        canrun = true;
        postDelayed(autoview,Timea);
    }
    //停止滚动
    public void stop() {
        running = false;
        removeCallbacks(autoview);
    }

    @Override
    public boolean onTouchEvent(MotionEvent e) {
        return super.onTouchEvent(e);
    }
}

2、适配器 MyscrviewAdapter

public class MyscrviewAdapter extends RecyclerView.Adapter<ViewHolder> {

    Context context;
    List<NoticeBean.RecordsBean> mies;
    private int itemCount = Integer.MAX_VALUE;

    public MyscrviewAdapter(Context context, List<NoticeBean.RecordsBean> mies) {
        this.context = context;
        this.mies = mies;
    }

    public void updateAll(List<NoticeBean.RecordsBean> list) {
        mies.clear();
        mies.addAll(list);
        notifyDataSetChanged();
    }

    /**
     * 设置状态，用于设置ItemCount的数量
     * state：1 表示正在手指滑动，itemCount设置为实际数量；
     * 其他的表示结束手动滑动，itemCount设置为最大值Integer.MAX_VALUE
     * @param state
     */
    public void setItemCount(int state) {
        this.itemCount = state == 1 ? mies.size() : Integer.MAX_VALUE;
        notifyDataSetChanged();
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View inflate = LayoutInflater.from(context).inflate(R.layout.item_home_news, parent, false);
        ViewHolder baseViewHolder = new ViewHolder(inflate);
        return baseViewHolder;
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, final int position) {
        holder.setText(R.id.tvNewsTitle, mies.get(position % mies.size()).getTitle());
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (null != mItemClickListener) {
                    mItemClickListener.onItemClick(mies.get(position % mies.size()), position);
                }
            }
        });
    }

    @Override
    public int getItemCount() {
        return mies.size() > 4 ? itemCount : mies.size();
    }

    //使用接口回调点击事件
    private ItemClickListener mItemClickListener;

    public void setOnItemClickListener(ItemClickListener itemClickListener) {
        this.mItemClickListener = itemClickListener;
    }
    
    public interface ItemClickListener {
        void onItemClick(Object obj, int position);
    }
}

ViewHolder封装类

public class ViewHolder extends RecyclerView.ViewHolder {
    //用于缓存已找的界面
    private SparseArray<View> mView;

    public ViewHolder(View itemView) {
        super(itemView);
        mView=new SparseArray<>();
    }
    public <T extends View> T getView(int viewId){
        //对已有的view做缓存
        View view=mView.get(viewId);
        //使用缓存的方式减少findViewById的次数
        if(view==null){
            view=itemView.findViewById(viewId);
            mView.put(viewId,view);
        }
        return (T) view;
    }
    //通用的功能进行封装  设置文本 设置条目点击事件  设置图片
    public ViewHolder setText(int viewId , CharSequence text){
        TextView view = getView(viewId);
        view.setText(text);
        //希望可以链式调用
        return this;
    }

    //通用的功能进行封装  设置文本 设置条目点击事件  设置图片
    public ViewHolder setText(int viewId , String text){
        TextView view = getView(viewId);
        view.setText(text);
        //希望可以链式调用
        return this;
    }

    public ViewHolder setSelected(int viewId ,boolean selected){
        TextView view = getView(viewId);
        view.setSelected(selected);
        //希望可以链式调用
        return this;
    }

    public ViewHolder setSelected2(int viewId,boolean selected){
        View view = getView(viewId);
        view.setSelected(selected);
        return this;
    }

    public ViewHolder setVisible(int viewId,boolean visible){
        View view = getView(viewId);
        view.setVisibility(visible ? View.VISIBLE : View.GONE);
        return this;
    }

    public ViewHolder setVisible(int viewId,boolean visible,boolean isLocation){
        View view = getView(viewId);
        if (isLocation){
            view.setVisibility(visible ? View.VISIBLE : View.INVISIBLE);
        }else{
            view.setVisibility(visible ? View.VISIBLE : View.GONE);
        }

        return this;
    }

    /**
     *设置本地图片
     * @param viewId
     * @param resId
     * @return
     */
    public ViewHolder setImageResource(int viewId,int resId){
        ImageView iv=getView(viewId);
        iv.setImageResource(resId);
        return this;
    }

    public ViewHolder setTextSelected(int viewId, boolean bool) {
        TextView tv = getView(viewId);
        tv.setSelected(bool);
        return this;
    }

    /**
     *设置本地图片
     * @param viewId
     * @param resId
     * @return
     */
    public ViewHolder setImageDrawable(Context mContext, int viewId, int resId){
        ImageView iv=getView(viewId);
        iv.setImageDrawable(mContext.getResources().getDrawable(resId));
        return this;
    }

    /**
     * 加载图片资源路径
     * @param viewId
     * @param imageLoader
     * @return
     */
    public ViewHolder setImagePath(int viewId,HolderImageLoader imageLoader,int res){
        ImageView iv=getView(viewId);
        imageLoader.loadImage(iv,imageLoader.getPath(),res);
        return this;
    }

    public ViewHolder setImage(Context mContext, int viewId, String url, int res) {
        ImageView view = getView(viewId);
        GlideLoadImageUtils.loadRectangleImg(mContext, view, url,res);
        return this;
    }

    public ViewHolder setCircleImage(Context mContext, int viewId, String url, int res) {
        ImageView view = getView(viewId);
        GlideLoadImageUtils.loadCircleImg(mContext, view, url,res);
        return this;
    }

    public ViewHolder setTextColor(Context mContext, int viewId, int color) {
        TextView tv = (TextView)this.getView(viewId);
        tv.setTextColor(mContext.getResources().getColor(color));
        return this;
    }

    public ViewHolder setTextSize(Context mContext, int viewId, float res) {
        TextView tv = (TextView)this.getView(viewId);
        tv.setTextSize(Utils.dp2px(mContext,res));
        return this;
    }

    @SuppressLint("NewApi")
    public ViewHolder setBackground(Context mContext, int viewId, int bg) {
        TextView tv = (TextView)this.getView(viewId);
        tv.setBackground(mContext.getResources().getDrawable(bg));
        return this;
    }

    /**
     * 关于事件的
     */
    public ViewHolder setOnClickListener(int viewId, View.OnClickListener listener) {
        View view = getView(viewId);
        view.setOnClickListener(listener);
        return this;
    }

    public abstract static class HolderImageLoader{
        public String mPath;
        public Context mContext;
        public HolderImageLoader(Context mContext, String path){
            this.mPath=path;
            this.mContext = mContext;
        }

        /**
         * 需要去复写这个方法加载图片
         * @param iv
         * @param path
         */
        public abstract void loadImage(ImageView iv, String path, int res);
        public String getPath(){
            return mPath;
        }
    }

}

3、activity中使用

     RecyclerView滑动监听，注释都说的很详细

/**
     * 控制通知公告数据滚动
     * 手指滑动时 停止自动滚动
     * 手指抬起时，3秒后自动开始滚动
     */
    private void initRlvNews() {
        scroHandler = new Handler();//定义handler
        runnable = () -> {  //runnable方法，处理延时后的操作
            newsAdapter.setItemCount(0);//0表示手指已经抬起来了
            rlvNews.start(); //开始滑动
        };
        rlvNews.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(@NonNull RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
                if (null != newsAdapter) {
                    if (newState == 1) {//newState的值：1 手指按下拖拽滚动，2自动滚动(一般指惯性滚动)，0 禁止没有滚动
                        rlvNews.stop();//停止自动滚动
                        newsAdapter.setItemCount(newState);
                    } else {
                        scroHandler.removeCallbacks(runnable);//清除runnable重新开始
                        //这里设置3秒是预估了手指滑动抬起再滑动的时间，提升体验
                        scroHandler.postDelayed(runnable, 3000);
                    }
                }
            }
        });
    }

4、布局文件：

  需要给固定高度

<com.anyi.credit.bank.view.SocllRecyclerView
 android:id="@+id/rlvNews"
 android:layout_width="match_parent"
 android:layout_height="144dp"/>

5、数据绑定

         rlvNews.setLayoutManager（）//可设置水平滚动或竖直滚动布局

        MyscrviewAdapter adpter=new MyscrviewAdapter(this,list)

        rlvNews.setAdapter(adpter)

        //关键，条件自定义，如当列表数据大于4条时开始滑动

        if（list.size()>4）{

                rlvNews.start(); //开始滑动

        }文章来源地址https://www.toymoban.com/news/detail-816609.html

结束------------

到了这里，关于Android 自动滚动的RecyclerView，手动滑动和自动滑动无缝衔接，手动滑动时数据不重复的文章就介绍完了。如果您还想了解更多内容，请在右上角搜索TOY模板网以前的文章或继续浏览下面的相关文章，希望大家以后多多支持TOY模板网！