选定的选项卡没有传递到tablayout中的片段

Question

在一个简单的tabLayout view viewPager设置中，我无法正确地将选定的选项卡传递到其中的片段。当从左到右选择选项卡时（即Tab1->tab x)，该选项卡被正确解释，但当它们从右到左选择时，返回0。

下面是重要的代码：

TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);

    ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
    viewPager.setAdapter(new OwnPagerAdapter(getSupportFragmentManager(), NavDrawer.this));

    tabLayout.setupWithViewPager(viewPager);

public class OwnPagerAdapter extends FragmentPagerAdapter {
private int TAB_COUNT = 7;
private String tabTitles[] = new String[] {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" };
private Context context;

public OwnPagerAdapter(FragmentManager fm, Context context) {
    super(fm);
    this.context = context;

}

@Override
public Fragment getItem(int position) {
    return OwnTimetableFragment.newInstance(position - 1);
}

@Override
public int getCount() {
    return TAB_COUNT;
}

@Override
public CharSequence getPageTitle(int position) {
    return tabTitles[position];
}
}

public class OwnTimetableFragment extends Fragment {

public static final String ARG_DAY = "ARG_DAY";

private int mDay;

public static OwnTimetableFragment newInstance(int day) {
    Bundle args = new Bundle();
    args.putInt(ARG_DAY, day);
    OwnTimetableFragment fragment = new OwnTimetableFragment();
    fragment.setArguments(args);
    return fragment;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mDay = getArguments().getInt(ARG_DAY);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View tabView = inflater.inflate(R.layout.fragment_own_timetable, container, false);
Log.e("mDay", mDay + "");
    return tabView;
}

似乎有一些碎片进入和离开焦点可能是导致这一点的原因？

Answer 1

首先，在新实例中传递pos-1，因此，第一个选项卡将log显示为-1。如果您想要正确的值，只需在NewInstance中传递pos。除此之外，请确保在ViewPager中没有传递任何setOffscreenPageLimit。代码中的其他内容似乎都是正常的。让我知道你的确切问题，如果你仍然面临它。