Fragment中使用ViewPager滑动浏览页面

在开发中有时会遇到需要在fragment使用viewPager滑动，使用tablayout + viewPager也好，RecyclerView + ViewPager也好，达到目的就行。

我这里使用的是RecyclerView + ViewPager，达到在fragment中滑动浏览页面新闻，开撸

newFragment布局

准备CenterLayoutManager，这是RecyclerView在点击item时会滑动到中心位置

public class CenterLayoutManager extends LinearLayoutManager {

    static int lastPosition = 0;
    static int targetPosition = 0;

    public CenterLayoutManager(Context context, int orientation, boolean reverseLayout) {
        super(context, orientation, reverseLayout);
    }

    @Override
    public void smoothScrollToPosition(RecyclerView recyclerView, RecyclerView.State state, int position) {
        CenterSmoothScroller smoothScroller = new CenterSmoothScroller(recyclerView.getContext());
        smoothScroller.setTargetPosition(position);
        startSmoothScroll(smoothScroller);
    }

    public void smoothScrollToPosition(RecyclerView recyclerView, RecyclerView.State state, int lastPosition, int position) {
        CenterLayoutManager.lastPosition = lastPosition;
        CenterLayoutManager.targetPosition = position;
        smoothScrollToPosition(recyclerView, state, position);
    }

    public static class CenterSmoothScroller extends LinearSmoothScroller {
        private static float duration = 200f;

        public CenterSmoothScroller(Context context) {
            super(context);
        }

        @Override
        public int calculateDtToFit(int viewStart, int viewEnd, int boxStart, int boxEnd, int snapPreference) {
            return (boxStart + (boxEnd - boxStart) / 2) - (viewStart + (viewEnd - viewStart) / 2);
        }

        @Override
        protected float calculateSpeedPerPixel(DisplayMetrics displayMetrics) {
            float newDuration = duration / (Math.abs(targetPosition - lastPosition));
            return newDuration / displayMetrics.densityDpi;
        }

        @Override
        protected int calculateTimeForScrolling(int dx) {
            return super.calculateTimeForScrolling(dx);
        }
    }
}

WrapLinearLayoutManager，这个具体是RecyclerView 界面在展示的时候出现下标越界的问题，但具体真的没什么用，RecyclerView出现下标越界的问题时主要是list.clear()后直接list.addAll，暂时找到的解决方法是list.clear之后也需要adapternotifyDataSetChanged

public class WrapLinearLayoutManager extends LinearLayoutManager {
    public WrapLinearLayoutManager(Context context) {
        super(context);
    }

    public WrapLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
        super(context, orientation, reverseLayout);
    }

    public WrapLinearLayoutManager(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    @Override
    public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {
        try {
            super.onLayoutChildren(recycler, state);
        } catch (IndexOutOfBoundsException e) {
            e.printStackTrace();
        }
    }
}

再准备一个继承View的类，作为添加到viewPager中的内容

public class HomeNewPagerDataView extends LinearLayout {

    private Context context;
    private LayoutInflater inflater;
    private View view;

    private RecyclerView homePagerRecView;
    private List