I guess the reason why it is not showing properly it is because you don’t have the oncreate() implemented in your project so under

private ViewPager mMyViewPager;
private TabLayout mTabLayout;

Add this :

 override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.main);

}

Don’t forget to delete this line of code setContentView(R.layout.main); from your Init function

My problem is when I go to a viewpager it shows for a second and then I get a blank page and I don’t where is the problem.

Here is my code to go from an activity to a viewpager:

final WordAdapter adapter = new WordAdapter(this, words,R.color.category_numbers);
        // Find the {@link ListView} object in the view hierarchy of the {@link Activity}.
        // There should be a {@link ListView} with the view ID called list, which is declared in the
        // activity_numbers.xml layout file.
        // word_list.xml layout file.

        final ListView listView = (ListView) findViewById(R.id.list);
        // Make the {@link ListView} use the {@link WordAdapter} we created above, so that the
        // {@link ListView} will display list items for each {@link Word} in the list.
        listView.setAdapter(adapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                Intent intent = new Intent(getApplicationContext(),Main.class);
                adapter.getItemId(i);
                init(i);
                startActivity(intent);
            }
        });

And my the viewpager is here:

    public class Main extends AppCompatActivity {
        // widgets
        private ViewPager mMyViewPager;
        private TabLayout mTabLayout;
    
    
       @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }

    public void init(int i) {
        mTabLayout = findViewById(R.id.tab_layout);
        mMyViewPager = findViewById(R.id.view_pager);
        ArrayList<Fragment> fragments = new ArrayList<>();
        Hat[] hats = Hats.getHats();
        for (Hat hat : hats) {
            com.example.android.miwok.ViewPagerItemFragment fragment = com.example.android.miwok.ViewPagerItemFragment.getInstance(hat);
            fragments.add(fragment);
        }
        MyPagerAdapter pagerAdapter = new MyPagerAdapter(getSupportFragmentManager() , fragments);
        mMyViewPager.setAdapter(pagerAdapter);
        mTabLayout.setupWithViewPager(mMyViewPager);
        mMyViewPager.setCurrentItem(i);
    }
}

Xml for viewpager is:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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=".Main"
    android_orientation="vertical"
    android_weightSum="100"
    android_background="#fff">

    <android.support.v4.view.ViewPager
        android_layout_width="match_parent"
        android_layout_height="0dp"
        android_id="@+id/view_pager"
        android_layout_weight="90">

    </android.support.v4.view.ViewPager>

    <android.support.design.widget.TabLayout
        android_id="@+id/tab_layout"
        android_layout_width="match_parent"
        android_layout_height="wrap_content"
        app_tabBackground="@drawable/tab_selector"
        app_tabGravity="center"
        app_tabIndicatorHeight="0dp"
        app_tabMaxWidth="10dp"/>
</LinearLayout>

And my is here Pageadapter:

public class MyPagerAdapter extends FragmentStatePagerAdapter {

    private ArrayList<Fragment> mFragments = new ArrayList<>();

    public MyPagerAdapter(FragmentManager fm, ArrayList<Fragment> fragments) {
        super(fm);
        mFragments = fragments;
    }

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

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

I edited my code here so you can know more about my code hope someone can help!