The specified child already has a parent. You must call removeView() on the child's parent first，

关于ViewPager+Fragment 滑动时 报java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child’s parent first，

    private class ContentFragmentViewPagerAdapter extends FragmentPagerAdapter {

        public ContentFragmentViewPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public int getCount() {
            return mFragments.size();
        }

        @Override
        public SubBaseFragment getItem(int position) {
            return mFragments.get(position);
        }
    }

public abstract class SubBaseFragment extends Fragment {

    private View mRootView;

    public SubBaseFragment() {
        super();
    }

    // 初始化数据
    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mRootView = initView();
        ButterKnife.inject(this, mRootView);
    }

    // 加载Fragment布局的方法
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        container.addView(mRootView);
        return mRootView;
    }

    // 加载显示数据的方法，类似于Activity中的onCreate
    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        initData();
        super.onActivityCreated(savedInstanceState);
    }

    public abstract View initView();

    protected abstract void initData();
}

解决方法一：

        mContentContainer.setOffscreenPageLimit(6); <!-- 这里的数字必须大于Fragment的个数 -->