Go to specific tab on Android

Question

What I want to achieve is when I'm on an Activity, if I click a specific button, a specific tab should be open in another activity. Here is my failed attempt, with this code always first tab is opened.

Here is first Activity's code :

holder.btn_ayarlar.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View arg0) {

        Intent intent = new Intent(mContext, IsActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

        intent.putExtra("Tabno", 8);

        mContext.getApplicationContext().startActivity(intent);

    }

});

Here is second activity's code :

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

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

        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        Intent i = getIntent();
        int tabToOpen = i.getIntExtra("Tabno", 1);


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

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


    }

How can I fix this situation? Thanks.