ViewPager

先建一个带底部菜单的

ViewPager切换 碎片

1、activity_main.xml

    <android.support.v4.view.ViewPager
        android:id="@+id/viewpager_a"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></android.support.v4.view.ViewPager>

2、根据引导创建两个Fragment

public class MainActivity extends AppCompatActivity implements BlankFragmentM.OnFragmentInteractionListener,PlusOneFragment.OnFragmentInteractionListener {

    private TextView mTextMessage;

    private ViewPager viewPager;
    private List<Fragment> fragmentList = new ArrayList<>();
    private BlankFragmentM fragmentM;
    private PlusOneFragment fragmentN;
    private MyPagerAdapter adapter;


    private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
            = new BottomNavigationView.OnNavigationItemSelectedListener() {

        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            switch (item.getItemId()) {
                case R.id.navigation_home:
                    mTextMessage.setText(R.string.title_home);
                    viewPager.setCurrentItem(0);
                    return true;
                case R.id.navigation_dashboard:
                    mTextMessage.setText(R.string.title_dashboard);
                    viewPager.setCurrentItem(1);
                    return true;
                case R.id.navigation_notifications:
                    mTextMessage.setText(R.string.title_notifications);
                    viewPager.setCurrentItem(0);
                    return true;
            }
            return false;
        }
    };

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

        mTextMessage = (TextView) findViewById(R.id.message);
        BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);
        navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);

        bindID();
        fragmentM = new BlankFragmentM();
        fragmentN = new PlusOneFragment();
        //填充数据
        fragmentList.add(fragmentM);
        fragmentList.add(fragmentN);

        adapter = new MyPagerAdapter(getSupportFragmentManager(),fragmentList);
        viewPager.setAdapter(adapter);
        viewPager.setCurrentItem(0);

    }
    private void bindID() {
        viewPager = findViewById(R.id.viewpager_a);
    }

    @Override
    public void onFragmentInteraction(Uri uri) {

    }


    public class MyPagerAdapter extends FragmentPagerAdapter {

        private List<Fragment> mfragmentList;

        public MyPagerAdapter(FragmentManager fm, List<Fragment> fragmentList) {
            super(fm);
            this.mfragmentList = fragmentList;
        }

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

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

}