添加到 viewpager 的片段是空的

Question

片段在 viewpager 中显示一个空白屏幕

已使用此库添加标签gihub

添加片段参考此方案adding fragments to viewpager

这里是代码

public class HorizontalNtbActivity extends android.support.v4.app.FragmentActivity {


@Override

protected void onCreate(final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_horizontal_ntb);


    initUI();
}

private void initUI() {

    CreateFragment createFragment = new CreateFragment();
    GroupFragment groupFragment= new GroupFragment();
    HomeFragment homeFragment= new HomeFragment();
    ProfileFragment profileFragment = new ProfileFragment();
    DashPagerAdapter dashPagerAdapter = new DashPagerAdapter(getSupportFragmentManager(),4);
    dashPagerAdapter.addFragment(homeFragment);
    dashPagerAdapter.addFragment(createFragment);
    dashPagerAdapter.addFragment(profileFragment);
    dashPagerAdapter.addFragment(groupFragment);
    final ViewPager viewPager = (ViewPager) findViewById(R.id.vp_horizontal_ntb);
    viewPager.setAdapter(dashPagerAdapter); 


    final String[] colors = getResources().getStringArray(R.array.tabcolors);

    final NavigationTabBar navigationTabBar = (NavigationTabBar) findViewById(R.id.ntb_horizontal);

    final ArrayList<NavigationTabBar.Model> models = new ArrayList<>();
    models.add(
            new NavigationTabBar.Model.Builder(

                    getResources().getDrawable(R.drawable.ic_first),
                    Color.parseColor(colors[0]))
                    .selectedIcon(getResources().getDrawable(R.drawable.ic_sixth))
                    .title("Home")
                    .badgeTitle("NTB")
                    .build()
    );
    models.add(
            new NavigationTabBar.Model.Builder(
                    getResources().getDrawable(R.drawable.ic_second),
                    Color.parseColor(colors[1]))
                    .selectedIcon(getResources().getDrawable(R.drawable.ic_eighth))
                    .title("Groups")
                    .badgeTitle("with")
                    .build()
    );
    models.add(
            new NavigationTabBar.Model.Builder(
                    getResources().getDrawable(R.drawable.ic_third),
                    Color.parseColor(colors[2]))
                    .selectedIcon(getResources().getDrawable(R.drawable.ic_seventh))
                    .title("Create")
                    .badgeTitle("state")
                    .build()
    );
    models.add(
            new NavigationTabBar.Model.Builder(
                    getResources().getDrawable(R.drawable.ic_fourth),
                    Color.parseColor(colors[3]))
                    .selectedIcon(getResources().getDrawable(R.drawable.ic_eighth))
                    .title("Profile")
                    .badgeTitle("icon")
                    .build()
    );
    navigationTabBar.setBgColor(Color.parseColor("#424242"));
    navigationTabBar.setActiveColor(Color.parseColor("#ffffff"));

    navigationTabBar.setInactiveColor(Color.parseColor("#9E9E9E"));
    navigationTabBar.setModels(models);
    navigationTabBar.setViewPager(viewPager, 0);
    navigationTabBar.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(final int position, final float positionOffset, final int positionOffsetPixels) {

        }

        @Override
        public void onPageSelected(final int position) {
            navigationTabBar.getModels().get(position).hideBadge();

            Toast.makeText(HorizontalNtbActivity.this, "" + position, Toast.LENGTH_SHORT).show();

        }

        @Override
        public void onPageScrollStateChanged(final int state) {

        }
    });

    navigationTabBar.postDelayed(new Runnable() {
        @Override
        public void run() {
            for (int i = 0; i < navigationTabBar.getModels().size(); i++) {
                final NavigationTabBar.Model model = navigationTabBar.getModels().get(i);
                navigationTabBar.postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        model.hideBadge();
                    }
                }, i * 100);
            }
        }
    }, 500);
}}

这是适配器

public class DashPagerAdapter extends FragmentPagerAdapter {
public final List<Fragment> fragments = new ArrayList<>();

public DashPagerAdapter(FragmentManager fm, int NumOfTabs) {

    super(fm);
    this.mNumOfTabs = NumOfTabs;
}

int mNumOfTabs;

@Override
public Fragment getItem(int position) {
    switch (position) {
        case 0: {
            return HomeFragment.newInstance("sdfsdfsdfsdf");
        }
        case 1: {
            return CreateFragment.newInstance("adfsdfsfd");
        }

        case 2: {
            return GroupFragment.newInstance("adfsdfsfd");
        }
        case 3: {
            return ProfileFragment.newInstance("abcd");

        }
        default:
            return null;

    }
}

public void addFragment(Fragment fragment) {
    fragments.add(fragment);
    notifyDataSetChanged();
}

@Override
public boolean isViewFromObject(final View view, final Object object) {
    return view.equals(object);
}

@Override
public int getCount() {
    return 4;
}
}

这是一个片段。所有其他片段都相似

public class HomeFragment extends Fragment {

public HomeFragment() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_home, container, false);
    TextView textView = (TextView) view.findViewById(R.id.homefragmenttextview);
    textView.setText(getArguments().getString("msg"));
    // Inflate the layout for this fragment
    return view;
}

public static HomeFragment newInstance(String text) {

    Bundle args = new Bundle();
    args.putString("msg", text);

    HomeFragment fragment = new HomeFragment();
    fragment.setArguments(args);
    return fragment;
}
}

这是它的外观 image for reference

Answer 1

在你的适配器中，改变这个

 @Override
 public boolean isViewFromObject(final View view, final Object object) 
 { 
     return view.equals(object); 
 } 

到这里

 @Override
 public boolean isViewFromObject(final View view, final Object object) 
 {
     return view == object; 
 }