how to set default fragment android studio?

Question

Hello every body i made a weather application and i have 3 tabs i want to make tab 2 the default tab when i run the app

that's my code :

public class SectionsPagerAdapter extends FragmentPagerAdapter {

    public SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
      switch (position)
      {
          case 0:
              Tab1 tab1=new Tab1();
              return tab1;
          case 1:
              Tab2 tab2=new Tab2();
              return tab2;
          case 2:
              Tab3 tab3=new Tab3();
              return tab3;
      }
        return null;
    }

    @Override
    public int getCount() {
        // Show 3 total pages.
        return 3;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        switch (position) {
            case 0:
                return "NextDay";
            case 1:
                return "Today";
            case 2:
                return "3rd Day";
        }
        return null;
    }
}

Answer 1

In your host Activity, at the end of onCreate call mViewPager.setCurrentItem(1);

Answer 2

You can go with this one. After setting the adapter in your host activity you should set the current item to 1.

public class MyActivity extends AppCompatActivity{

     SectionsPagerAdapter pagerAdapter;
     ViewPager myViewPager;
     public static final int PAGER_CURRENT_ITEM = 1;

     @Override
     protected void onCreate(Bundle savedInstanceState){
            setContentView(R.layout.activity_main);
            myViewPager = (ViewPager) findViewById(R.is.view_pager_id);
            pagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
            viewPager.setAdapter(pagerAdapter)
            viewPager.setCurrentItem(PAGER_CURRENT_ITEM);
     }
}