使用TabLayout、ViewPager和Fragment实现顶部菜单可滑动切换

<?xml version="1.0" encoding="utf-8"?>  
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    xmlns:tools="http://schemas.android.com/tools"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    xmlns:app="http://schemas.android.com/apk/res-auto"  
    tools:context="com.lg.tablayoutdemo.MainActivity">  
  
    <android.support.design.widget.TabLayout  
        android:id="@+id/tab_layou"  
        android:layout_width="match_parent"  
        app:tabIndicatorColor="@android:color/holo_blue_light"  
        app:tabTextColor="@android:color/darker_gray"  
        app:tabSelectedTextColor="@android:color/black"  
        android:layout_height="wrap_content" />  
  
    <android.support.v4.view.ViewPager  
        android:id="@+id/view_pager"  
        android:layout_below="@id/tab_layou"  
        android:layout_width="match_parent"  
        android:layout_height="match_parent" />  
  
</RelativeLayout>

public class MyViewPagerAdapter extends FragmentPagerAdapter {  
    private List<Fragment> fragments;  
    private String[] titles;  
  
    public MyViewPagerAdapter(FragmentManager fm, String[] titles, List<Fragment> fragments) {  
        super(fm);  
        this.titles = titles;  
        this.fragments = fragments;  
    }  
  
    @Override  
    public Fragment getItem(int arg0) {  
        return fragments.get(arg0);  
    }  
  
    @Override  
    public CharSequence getPageTitle(int position) {  
        return titles[position];  
    }  
  
    @Override  
    public int getCount() {  
        return fragments.size();  
    }  
}

public class MainActivity extends AppCompatActivity implements TabLayout.OnTabSelectedListener {  
    private TabLayout tabLayout;  
    private ViewPager viewPager;  
    private MyViewPagerAdapter viewPagerAdapter;  
    //TabLayout标签  
    private String[] titles=new String[]{"ANDROID","JAVA","C#","PHP"};  
    private List<Fragment> fragments=new ArrayList<>();  
  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_main);  
        init();  
    }  
  
    private void init(){  
        tabLayout=(TabLayout)findViewById(R.id.tab_layou);  
        viewPager=(ViewPager)findViewById(R.id.view_pager);  
        //设置TabLayout标签的显示方式  
        tabLayout.setTabMode(TabLayout.MODE_FIXED);  
        //循环注入标签  
        for (String tab:titles){  
          tabLayout.addTab(tabLayout.newTab().setText(tab));  
        }  
        //设置TabLayout点击事件  
        tabLayout.setOnTabSelectedListener(this);  
  
        fragments.add(new AndroidFragment());  
        fragments.add(new JavaFragment());  
        fragments.add(new CshapFragment());  
        fragments.add(new PhpFragment());  
        viewPagerAdapter=new MyViewPagerAdapter(getSupportFragmentManager(),titles,fragments);  
        viewPager.setAdapter(viewPagerAdapter);  
        tabLayout.setupWithViewPager(viewPager);  
    }  
  
    @Override  
    public void onTabSelected(TabLayout.Tab tab) {  
        viewPager.setCurrentItem(tab.getPosition());  
    }  
  
    @Override  
    public void onTabUnselected(TabLayout.Tab tab) {  
  
    }  
  
    @Override  
    public void onTabReselected(TabLayout.Tab tab) {  
  
    }  
}