如何使用导航抽屉和viewpager/viewpager2在java中制作android应用程序

Question

hello I am making an application to debate in android studio using Java, I intend that the application occupies a navigation drawer and a viewpager / viewpager2. I am very new programming in androidstudio and therefore I have followed several video tutorials to incorporate viewpager / viepager 2 with navigation drawer but so far none works for me (the navigation drawer only works for me), the last thing I tried was to use viewpager (since with viepager 2 I had problems calling the adapter from the main), but when compiling the project the emulator was I was left with a black screen and it did not show anything. I hope you can help me because this project is very important to me. Here is part of my code:

main:

import androidx.annotation.NonNull;
import androidx.appcompat.app.ActionBarDrawerToggle;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import androidx.core.view.GravityCompat;
import androidx.drawerlayout.widget.DrawerLayout;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentPagerAdapter;
import androidx.fragment.app.FragmentTransaction;
import androidx.viewpager.widget.PagerAdapter;
import androidx.viewpager.widget.ViewPager;
import androidx.viewpager2.adapter.FragmentStateAdapter;
import androidx.viewpager2.widget.ViewPager2;


import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.MenuItem;
import android.widget.Toast;

import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.material.appbar.AppBarLayout;
import com.google.android.material.navigation.NavigationView;
import com.google.android.material.tabs.TabItem;
import com.google.android.material.tabs.TabLayout;
import com.google.android.material.tabs.TabLayoutMediator;

import Fragments.generaDebate;
import Fragments.perfil_user;

public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
    DrawerLayout drawerLayout;
    ActionBarDrawerToggle actionBarDrawerToggle;
    Toolbar toolbar;
    NavigationView navigationView;
    //variables para cargar el fragment
    FragmentManager fragmentManager;
    FragmentTransaction fragmentTransaction;
    String personName;
    //variable viewpager
    ViewPager pager;
    TabLayout tablayout;
    TabItem first_item,second_item;
    pageAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        toolbar=findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);//se pasa el toolbar
        drawerLayout=findViewById(R.id.drawer);
        navigationView=findViewById(R.id.navigationView);
        navigationView.setNavigationItemSelectedListener(this);
        actionBarDrawerToggle=new ActionBarDrawerToggle(this,drawerLayout,toolbar,R.string.open,R.string.close);
        drawerLayout.addDrawerListener(actionBarDrawerToggle);
        actionBarDrawerToggle.setDrawerIndicatorEnabled(true);
        actionBarDrawerToggle.syncState();
        //carga viewpager
        pager=findViewById(R.id.view);
        tablayout=findViewById(R.id.title_menu);
        first_item=findViewById(R.id.first_item);
        second_item=findViewById(R.id.second_item);
        //declarando adapter en el main
        FragmentManager fragmentManager;
        fragmentManager=getSupportFragmentManager();
        adapter=new pageAdapter(fragmentManager, FragmentPagerAdapter.BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT,tablayout.getTabCount());
        pager.setAdapter(adapter);
        tablayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                pager.setCurrentItem(tab.getPosition());
            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {

            }
        });
        pager.addOnAdapterChangeListener((ViewPager.OnAdapterChangeListener) new TabLayout.TabLayoutOnPageChangeListener(tablayout));
        //cargar fragment principal
        FragmentTransaction fragmentTransaction;
        fragmentTransaction=fragmentManager.beginTransaction();
        fragmentTransaction.add(R.id.container, new perfil_user());
        fragmentTransaction.commit();



    }


    @Override
    public boolean onNavigationItemSelected(@NonNull MenuItem item) {
        if (item.getItemId() == R.id.user){
            FragmentManager fragmentManager;
            FragmentTransaction fragmentTransaction;
            fragmentManager=getSupportFragmentManager();
            fragmentTransaction=fragmentManager.beginTransaction();
            fragmentTransaction.replace(R.id.container, new perfil_user());
            fragmentTransaction.commit();

        }
        else if (item.getItemId() == R.id.exit){
            //finish();
            loggin login=new loggin();
            login.signOut();
        }
        //aquí van las otros fragment
        drawerLayout.closeDrawer(GravityCompat.START);
        return false;
    }
}

adapter:

import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentPagerAdapter;
import androidx.lifecycle.Lifecycle;
import androidx.viewpager2.adapter.FragmentStateAdapter;

import java.util.ArrayList;

import Fragments.generaDebate;
import Fragments.perfil_user;


public class pageAdapter extends FragmentPagerAdapter {
    private int tabsNumber;

    public pageAdapter(@NonNull FragmentManager fm, int behavior,int tabs) {
        super(fm, behavior);
    }


    @NonNull
    @Override
    public Fragment getItem(int position) {
        switch (position){
            case 1:
                return new perfil_user ();
            case 2:
                return new generaDebate();
            default:
                return null;

        }
    }

    @Override
    public int getCount() {
        return tabsNumber;
    }
}

Answer 1

The navigation drawer is the most common feature offered by android and the navigation drawer is a UI panel that shows your app's main navigation menu. It is also one of the important UI elements, which provides actions preferable to the users like example changing user profile, changing settings of the application, etc. In this article, it has been discussed step by step to implement the navigation drawer in android

activity_main.xml

 <?xml version="1.0" encoding="utf-8"?>
    <androidx.coordinatorlayout.widget.CoordinatorLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:background="@color/bgColor"
    android:layout_height="match_parent"
    tools:context=".activities.MainActivity">

    <com.google.android.material.appbar.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:elevation="0dp">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:gravity="center_vertical"
            android:background="@color/bgColor"
            android:paddingStart="20dp"
            android:paddingEnd="20dp"
            android:orientation="horizontal">

        </LinearLayout>
    </com.google.android.material.appbar.AppBarLayout>

    <androidx.viewpager2.widget.ViewPager2
        android:id="@+id/vp_horizontal_ntb"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"/>

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/navigation"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:background="?android:attr/windowBackground"
        android:foreground="?attr/selectableItemBackground"
        app:menu="@menu/bottom_navigation"
        app:elevation="10dp"
        app:labelVisibilityMode="labeled"
        app:itemIconTint="@color/bottom_navigation_color"
        app:itemTextColor="@color/bottom_navigation_color"
        app:itemBackground="@color/bottomNavigationBackground"/>
</androidx.coordinatorlayout.widget.CoordinatorLayout>

menu.xml

    <?xml version="1.0" encoding="utf-8"?>
    <menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/navigationMenu"
        android:icon="@android:drawable/ic_menu_sort_by_size"
        android:title="Menu" />

    <item
        android:id="@+id/navigationMyCourses"
        android:icon="@drawable/ic_email"
        android:title="Courses" />

    <item
        android:id="@+id/navigationHome"
        android:icon="@drawable/ic_home"
        android:title="Home" />

    <item
        android:id="@+id/m_refer"
        android:icon="@android:drawable/ic_menu_share"
        android:title="Refer" />

    <item
        android:id="@+id/navigationMyProfile"
        android:icon="@drawable/ic_back"
        android:title="User" />
</menu>

ViewPagerAdapter.java

    public class ViewPagerAdapter extends FragmentStateAdapter {

    public ViewPagerAdapter(@NonNull @NotNull FragmentActivity fragmentActivity) {
        super(fragmentActivity);
    }

    @NonNull
    @NotNull
    @Override
    public Fragment createFragment(int p) {

        switch (p) {

            case 0:
                return new ProfileFragment();
            case 1:
                return new LeaderBoardFragment();
            case 2:
                return new HomeFragment();
            case 3:
                return new ReferFragment();
            case 4:
                return new ProfileFragment();
            default:
                return new HomeFragment();

        }
    }

    @Override
    public int getItemCount() {
        return 5;
    }
}

MainActivity.java

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initView();
  }

    private void initView() {
        this.viewPager2 = findViewById(R.id.vp_horizontal_ntb);
        viewPager2.setOffscreenPageLimit(100);
        this.bottomNavigationView = findViewById(R.id.navigation);
        adapter = new ViewPagerAdapter(this);
        viewPager2.setAdapter(adapter);

        viewPager2.registerOnPageChangeCallback(new ViewPager2.OnPageChangeCallback() {
            @Override
            public void onPageSelected(int position) {
                super.onPageSelected(position);

                switch (position) {
                    case 0:
                        bottomNavigationView.getMenu().findItem(R.id.navigationMenu).setChecked(true);
                        break;

                    case 1:
                        bottomNavigationView.getMenu().findItem(R.id.navigationMyCourses).setChecked(true);
                        break;

                    case 2:
                        bottomNavigationView.getMenu().findItem(R.id.navigationHome).setChecked(true);
                        break;

                    case 3:
                        bottomNavigationView.getMenu().findItem(R.id.m_refer).setChecked(true);
                        break;

                    case 4:
                        bottomNavigationView.getMenu().findItem(R.id.navigationMyProfile).setChecked(true);
                        break;

                }
            }
        });


        bottomNavigationView.setOnItemSelectedListener(new NavigationBarView.OnItemSelectedListener() {
            @SuppressLint("NonConstantResourceId")
            @Override
            public boolean onNavigationItemSelected(@NonNull @NotNull MenuItem item) {

                switch (item.getItemId()) {
                    case R.id.navigationHome:
                        viewPager2.setCurrentItem(2);
                        break;
                    case R.id.navigationMyProfile:
                        viewPager2.setCurrentItem(4);
                        break;
                    case R.id.m_refer:
                        viewPager2.setCurrentItem(3);
                        break;
                    case R.id.navigationMyCourses:
                        viewPager2.setCurrentItem(1);
                        break;
                    case R.id.navigationMenu:
                        viewPager2.setCurrentItem(0);
                        break;
                }
                return false;
            }
        });

        CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) bottomNavigationView.getLayoutParams();
        layoutParams.setBehavior(new BottomNavigationBehavior());
        bottomNavigationView.setSelectedItemId(R.id.navigationMenu);
    }
}

Happy Coding