Navigation drawer and Toolbar across all activities

Question

I would like to program a Toolbar with Navigation Drawer that appears on all activities of my app. To do so, I have created an abstract class "BaseActivity" which is then extended by all other activities.

I have succeeded in creating a Toolbar that appears on all activities. Here is a screenshot of what that looks like:

However, when I try to add a Navigation Drawer to that Toolbar, then the contents of the activities that are extending BaseActivity.java do not appear.

I am therefore wondering what I am doing wrong with the implementation of the Navigation Drawer for that to happen. Here is the layout of activity_base.xml

<?xml version="1.0" encoding="utf-8"?>
<merge xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <androidx.appcompat.widget.Toolbar
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:id="@+id/toolbar"
        android:background="?attr/colorPrimary"
        app:layout_scrollFlags="scroll|enterAlways"
        app:title="@string/app_name"
        app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/>

    <androidx.drawerlayout.widget.DrawerLayout
        android:id="@+id/drawer_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >

        <com.google.android.material.navigation.NavigationView
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_gravity="start"
            android:fitsSystemWindows="true"
            app:menu="@menu/nav_menu"
            android:id="@+id/nav_view"/>
    </androidx.drawerlayout.widget.DrawerLayout>

</merge>

And here is the java code for "BaseActivity.java":

package com.example.newsreader;

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 android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Toast;

import com.google.android.material.navigation.NavigationView;

public abstract class BaseActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {

    Toolbar toolbar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    protected boolean useToolbar() {
        return true;
    }

    @Override
    public void setContentView(int layoutResID) {
        View view = getLayoutInflater().inflate(layoutResID, null);
        configureToolbar(view);
        super.setContentView(view);

        //create NavigationDrawer:
        DrawerLayout drawer = findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.open, R.string.closed);
        drawer.addDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    private void configureToolbar(View view)  {
        toolbar = (Toolbar) view.findViewById(R.id.toolbar);
        if (toolbar != null)  {
            if (useToolbar())  {
                //loads toolbar and calls onCreateOptionsMenu
                setSupportActionBar(toolbar);


            } else  {
                toolbar.setVisibility(View.GONE);
            }
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu)  {
        //inflate menu items for use in action bar
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.menu, menu);

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        String message = null;
        //Look at your menu XML file. Put a case for every id in that file:
        switch(item.getItemId())
        {
            //what to do when the menu item is selected:
            case R.id.item1:
                message = "You clicked on item 1";
                break;
            case R.id.item2:
                message = "You clicked on item 2";
                break;
            case R.id.item3:
                message = "You clicked on item 3";
                break;
            case R.id.item4:
                message = "You clicked on the overflow menu";
                break;
        }
        Toast.makeText(this, message, Toast.LENGTH_LONG).show();
        return true;
    }

    // Needed for the OnNavigationItemSelected interface:
    @Override
    public boolean onNavigationItemSelected( MenuItem item) {

        String message = null;

        switch(item.getItemId())
        {
            case R.id.item1:
                Intent chatPage = new Intent(this, NewsHeadlines.class);
                startActivity(chatPage);
                break;
            case R.id.item2:
                Intent weatherForecastPage = new Intent(this, WeatherForecast.class);
                startActivity(weatherForecastPage);
                break;
            case R.id.item3:
                setResult(500);
                finish();
                break;
        }

        DrawerLayout drawerLayout = findViewById(R.id.drawer_layout);
        drawerLayout.closeDrawer(GravityCompat.START);

        return false;
    }
}

Any suggestions as to what I'm doing wrong?

Answer 1

It is highly recommended to use Fragments instead of Activity when we use Navigation Bar or Bottom Navigation Bar in our app.

Since you have used activity in your onNavigationItemSelected method, which is wrong:

Intent chatPage = new Intent(this, NewsHeadlines.class); startActivity(chatPage);

Instead, use Fragments like this > getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container, new **yourFragmentName**()).commit();