RecycleVIew自动循环滚动使用

package com.zhw.autorecycler.java; import androidx.appcompat.app.AppCompatActivity; import androidx.recyclerview.widget.DividerItemDecoration; import androidx.recyclerview.widget.LinearLayoutManager; import androidx.recyclerview.widget.LinearSmoothScroller; import android.os.Bundle; import android.util.DisplayMetrics; import com.zhw.autorecycler.R; import java.util.ArrayList; import java.util.List; import java.util.concurrent.TimeUnit; import io.reactivex.Observable; import io.reactivex.android.schedulers.AndroidSchedulers; import io.reactivex.disposables.Disposable; import io.reactivex.functions.Consumer; public class MainActivity extends AppCompatActivity { private AutoScrollRecyclerView mRv; private AutoScrollRecyclerView mRv1; private NoticeRecyclerViewAdapter mAdapter; private List<String> data = new ArrayList<>(); private LinearSmoothScroller smoothScroller; private Disposable mAutoTask; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initView(); } private void initData() { for (int i = 0; i < 10; i++) { data.add("测试机" + i); } } private void initView() { mRv = findViewById(R.id.am_rv); mRv1 = findViewById(R.id.am_rv1); initData(); mAdapter = new NoticeRecyclerViewAdapter(data); LinearLayoutManager layoutManager = new LinearLayoutManager(this); DividerItemDecoration decoration = new DividerItemDecoration(this, DividerItemDecoration.VERTICAL); mRv.setLayoutManager(layoutManager); mRv.addItemDecoration(decoration); mRv.setAdapter(mAdapter); mRv1.setLayoutManager(layoutManager); mRv1.addItemDecoration(decoration); mRv1.setAdapter(mAdapter); // 自定义LinearSmoothScroller，重写方法，滚动item至顶部，控制滚动速度 smoothScroller = new LinearSmoothScroller(this) { //将移动的置顶显示 @Override protected int getVerticalSnapPreference() { return LinearSmoothScroller.SNAP_TO_START; } //控制速度，这里注意当速度过慢的时候可能会形成流式的效果，因为这里是代表移动像素的速度， // 当定时器中每隔的2秒之内正好或者还未移动一个item的高度的时候会出现，前一个还没移动完成又继续移动下一个了，就形成了流滚动的效果了 // 这个问题后续可通过重写另外一个方法来进行控制，暂时就先这样了 @Override protected float calculateSpeedPerPixel(DisplayMetrics displayMetrics) { return 3f / displayMetrics.density; } }; } // 设置定时器自动滚动 public void startAuto() { if (mAutoTask != null && !mAutoTask.isDisposed()) { mAutoTask.dispose(); } mAutoTask = Observable.interval(500, 200, TimeUnit.MILLISECONDS) .observeOn(AndroidSchedulers.mainThread()) .subscribe(new Consumer<Long>() { @Override public void accept(Long aLong) throws Exception { //滚动到指定Item smoothScroller.setTargetPosition(aLong.intValue()); mRv.getLayoutManager().startSmoothScroll(smoothScroller); } }); } private void stopAuto() { if (mAutoTask != null && !mAutoTask.isDisposed()) { mAutoTask.dispose(); mAutoTask = null; } } @Override protected void onStop() { super.onStop(); //item滚动步骤3：开始滚动 startAuto(); //流式滚动效果 mRv1.start(); } @Override protected void onStart() { super.onStart(); //item滚动步骤4：结束滚动 stopAuto(); mRv1.stop(); } }