Question

我在应用程序选项卡Activity中创建ListView但是当app运行模拟器时显示空白活动。我不知道这是什么问题。请帮忙。我没有在选项卡中获得列表。我在没有标签的简单活动中获取列表但我无法在标签活动中看到列表。如果您需要其他信息，请告诉我。

这是我的 ArtistTab.java 活动

public class ArtistsTab extends Fragment {
    ListView listView1;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.artist, container, false);
        listView1 =(ListView)v.findViewById(R.id.listView);
        return v;
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        // add your code here which executes after the execution of onCreateView() method.
        ArrayList<String>my=new ArrayList<>();
        my.add("devesh");
        my.add("devesh");
        my.add("devesh");
        my.add("devesh");
        ArrayAdapter arrayAdapter=new ArrayAdapter(getActivity(), layout.simple_list_item_1,my);
        listView1.setAdapter(arrayAdapter);

    }

}

这是我的主要活动

public class MainActivity extends AppCompatActivity {

    public ViewPagerAdapter pagerAdapter;
    private ViewPager mViewPager;
    private Toolbar toolbar;
    private TabLayout tabLayout;
    public static View rootView;
    public static int tabNo;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        pagerAdapter = new ViewPagerAdapter(getSupportFragmentManager());
        mViewPager = (ViewPager) findViewById(R.id.container);
        tabLayout = (TabLayout) findViewById(R.id.tabs);
        tabLayout.setupWithViewPager(mViewPager);
        mViewPager.setAdapter(pagerAdapter);
        tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {


            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                mViewPager.setCurrentItem(tab.getPosition());//setting current selected item over viewpager
            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {
            }
        });
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }


    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();

        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    public static class PlaceholderFragment extends Fragment {

        private static final String ARG_SECTION_NUMBER = "section_number";

        public PlaceholderFragment() {
        }

        public static PlaceholderFragment newInstance(int sectionNumber) {
            PlaceholderFragment fragment = new PlaceholderFragment();

            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
//              View rootView;

            switch (getArguments().getInt(ARG_SECTION_NUMBER))
            {
                case 1: {
                    rootView = inflater.inflate(R.layout.songs, container, false);

                    break;
                }
                case 2: {
                    rootView = inflater.inflate(R.layout.album, container, false);
                    break;
                }

                case 3: {
                    rootView = inflater.inflate(R.layout.genres, container, false);
                    break;
                }
                case 4: {
                    rootView = inflater.inflate(R.layout.artist, container, false);
                    break;
                }

            }
            return rootView;


        }

    }
}

artistTab xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
    <ListView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/listView" />
</RelativeLayout>

Answer 1

请尝试tabs with viewpager

public class MainActivity extends AppCompatActivity {

private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    viewPager = (ViewPager) findViewById(R.id.viewpager);
    setupViewPager(viewPager);

    tabLayout = (TabLayout) findViewById(R.id.tabs);
    tabLayout.setupWithViewPager(viewPager);
}

private void setupViewPager(ViewPager viewPager) {
    ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
    adapter.addFragment(new ArtistsTab(), "ArtistsTab");
    adapter.addFragment(new SongsTab(), "Songs");
   //Do your stuff here
    viewPager.setAdapter(adapter);
}

class ViewPagerAdapter extends FragmentPagerAdapter {
    private final List<Fragment> mFragmentList = new ArrayList<>();
    private final List<String> mFragmentTitleList = new ArrayList<>();

    public ViewPagerAdapter(FragmentManager manager) {
        super(manager);
    }

    @Override
    public Fragment getItem(int position) {
        return mFragmentList.get(position);
    }

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

    public void addFragment(Fragment fragment, String title) {
        mFragmentList.add(fragment);
        mFragmentTitleList.add(title);
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return mFragmentTitleList.get(position);
    }
}
}

活动在标签活动中为空白

1 个答案: