android:background="?attr/colorPrimary"

android:background="?attr/colorPrimary"

app:title="App menu"

app:layout_constraintTop_toTopOf="parent"

android:minHeight="?attr/actionBarSize"

android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"

app:popupTheme="@style/ThemeOverlay.AppCompat.Light"

/>

MainActivity.java

package com.example.menuapp;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;

import android.view.Menu;

import androidx.appcompat.widget.Toolbar;

public class MainActivity extends AppCompatActivity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);