main_activity_layout

package com.example.mark3;

import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import androidx.viewpager.widget.ViewPager;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;

import com.google.android.material.tabs.TabLayout;
import com.google.android.material.appbar.AppBarLayout;
import androidx.appcompat.widget.Toolbar;

public class MainActivity extends AppCompatActivity {
    private Toolbar myToolbar;
    private TabLayout myTabLayout;
    private ViewPager myViewPager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        myToolbar=(Toolbar)findViewById(R.id.myToolbar);
        myTabLayout=(TabLayout)findViewById(R.id.myTab);
        myViewPager=(ViewPager)findViewById(R.id.myViewPager);
        setSupportActionBar(myToolbar);
        SetupViwPager(myViewPager);
        myTabLayout.setupWithViewPager(myViewPager);
    }
    private  void SetupViwPager(ViewPager viewPager)
    {
        ViewPagerAdapter viewpageradapter= new ViewPagerAdapter(getSupportFragmentManager());
        viewpageradapter.addFragment(new ChatFragment(),"Chats");
        viewpageradapter.addFragment(new GroupsFragment(),"Groups");
        viewpageradapter.addFragment(new ContactsFragment(),"Contacts");
            viewPager.setAdapter(viewpageradapter);
    }
}