Android使用RecycleView实现跑马灯和轮播图效果-轻识

先看下效果图：

利用Recycleview实现这个效果最主要的一个方法就是这个方法

        mSnapHelper = new LinearSnapHelper();        mSnapHelper.attachToRecyclerView(mRecyclerView);

这个方法的作用是使得RecycelView像ViewPager一样的效果，一次只能滑一页，而且居中显示。

然后利用Handler来实现无限轮播的效果,在Adapter中要注意

    @Override    public int getItemCount() {        return Integer.MAX_VALUE;    }

 Glide.with(mContext).load(mDatas.get(position % mDatas.size())).into(mImageView);

getItemCount中返回一个无穷大达到无限录播的效果,在填充数据时取余防止索引越界，然后自定义Layoutmanger

public class MyBannerManger extends LinearLayoutManager {
    private RecyclerView mRecyclerView;    private final InterValHander mHander;    private static final int INTERVAL = 3000;    private boolean mIsLayoutComplete = false;    private static int position = 1;    private LinearSnapHelper mSnapHelper;
    public MyBannerManger(Context context, RecyclerView recyclerView) {        super(context);        setOrientation(HORIZONTAL);        mRecyclerView = recyclerView;        mHander = new InterValHander(this);        mRecyclerView.setOnTouchListener(new View.OnTouchListener() {            @Override            public boolean onTouch(View v, MotionEvent event) {                if(event.getAction()  == MotionEvent.ACTION_DOWN){                    mHander.removeCallbacksAndMessages(null);                }else if(event.getAction()  == MotionEvent.ACTION_UP){                    mHander.sendEmptyMessageDelayed(position,INTERVAL);                }                return false;            }        });    }
    @Override    public void onAttachedToWindow(RecyclerView view) {        super.onAttachedToWindow(view);        mSnapHelper = new LinearSnapHelper();        mSnapHelper.attachToRecyclerView(mRecyclerView);    }
    @Override    public void onLayoutCompleted(RecyclerView.State state) {        super.onLayoutCompleted(state);        if (!mIsLayoutComplete) {            mHander.sendEmptyMessageDelayed(position,INTERVAL);        }
        mIsLayoutComplete = true;    }
    private RecyclerView getRecyclerView(){        return mRecyclerView;    }
    static class InterValHander extends Handler {
        private WeakReference<MyBannerManger> mWeakReference;        private MyBannerManger mBannerManger;
        public InterValHander(MyBannerManger myBannerManger) {            mWeakReference = new WeakReference<>(myBannerManger);            mBannerManger = myBannerManger;        }
        @Override        public void handleMessage(Message msg) {            LogUtils.LogE(msg.toString());            mBannerManger.getRecyclerView().smoothScrollToPosition(position);            sendEmptyMessageDelayed(0,INTERVAL);            position++;
        }    }

    @Override    public void smoothScrollToPosition(RecyclerView recyclerView, RecyclerView.State state, int position) {        LogUtils.LogE("smoothScrollToPosition");        LinearSmoothScroller smoothScroller =                new LinearSmoothScroller(recyclerView.getContext()) {                    // 返回：滑过1px时经历的时间(ms)。                    @Override                    protected float calculateSpeedPerPixel(DisplayMetrics displayMetrics) {                        float f = 150f / displayMetrics.densityDpi;                        LogUtils.LogE("F = "+f);                        return 0.5f;                    }                };
        smoothScroller.setTargetPosition(position);        startSmoothScroll(smoothScroller);    }
    @Override    public void onScrollStateChanged(int state) {        if(state == SCROLL_STATE_IDLE){            position = getPosition(mSnapHelper.findSnapView(this))+1;        }    }

处理逻辑：

public class RActivity extends AppCompatActivity {    private RecyclerView mRecyclerView;    private String[] mStrings = {"南京南站","龙眠大道","学则路","仙鹤门","仙鹤名苑","紫东国际创意园!"};
    @Override    protected void onCreate(@Nullable Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_r);        mRecyclerView = findViewById(R.id.rv);        List<String> list = Arrays.asList(Images.imageUrls);        mRecyclerView.setLayoutManager(new MyBannerManger(this,mRecyclerView));        RAdapter rAdapter = new RAdapter(this, list);        mRecyclerView.setAdapter(rAdapter);    }}

到这里就结束啦。