main menu android example

different files

res \ values \ strings.xml:

<resources>
    <string name="app_name">Menu Example</string>
    <string name="file">File</string>
    <string name="edit">Edit</string>
    <string name="view">View</string>
    <string name="navigate">Navigate</string>
</resources>

==================================================================

res \ menu \ menu.xml:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item
        android:id="@+id/action_file"
        android:orderInCategory="1"
        android:title="@string/file"
        app:showAsAction="never" />
    <item
        android:id="@+id/action_edit"
        android:orderInCategory="2"
        android:title="@string/edit"
        app:showAsAction="never" />
    <item
        android:id="@+id/action_view"
        android:orderInCategory="3"
        android:title="@string/view"
        app:showAsAction="never" />
    <item
        android:id="@+id/action_navigate"
        android:orderInCategory="4"
        android:title="@string/navigate"
        app:showAsAction="never" />
</menu>

==================================================================

MainActivity.java:

package com.sunmeat.myapplication;

import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

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

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu, menu);
        return true;
    }
    
    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        Toast.makeText(this, item.getTitle(), Toast.LENGTH_SHORT).show();
        return true;
    }
}

==================================================================

AndroidManifest.xml:

...
<application
        ...
        android:theme="@style/AppTheme"
        ...
        
==================================================================

res \ values \ themes.xml:

<resources>
    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
        <item name="android:windowBackground">@color/white</item>
        <item name="android:textColor">@color/black</item>
    </style>
    ...