android kotlin - Toolbar example

MainActivity.kt

package com.cfsuman.kotlintutorials

import android.graphics.Color
import android.os.Bundle
import android.view.Menu
import android.view.MenuItem
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity
import androidx.appcompat.widget.Toolbar


class MainActivity : AppCompatActivity() {
    private lateinit var textView: TextView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Get the widgets from XML layout
        val toolbar = findViewById<Toolbar>(R.id.toolbar);
        textView = findViewById(R.id.textView);

        // Configure the Toolbar
        toolbar.apply {
            title = "Toolbar title"
            setTitleTextColor(Color.WHITE)
            setLogo(R.drawable.ic_action_help)
            //subtitle = "Toolbar Subtitle"
            //setSubtitleTextColor(Color.WHITE)
        }

        // Set the toolbar as support action bar
        setSupportActionBar(toolbar)
    }


    override fun onCreateOptionsMenu(menu: Menu): Boolean {
        // Inflate the menu to use in the action bar
        val inflater = menuInflater
        inflater.inflate(R.menu.toolbar_menu, menu)
        return super.onCreateOptionsMenu(menu)
    }


    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        // Handle presses on the action bar menu items
        when (item.itemId) {
            R.id.action_cut -> {
                textView.text = "Cut Clicked."
                return true
            }
            R.id.action_copy -> {
                textView.text = "Copy Clicked."
                return true
            }
            R.id.action_paste -> {
                textView.text = "Paste Clicked."
                return true
            }
            R.id.action_new -> {
                textView.text = "New Clicked."
                return true
            }
        }
        return super.onOptionsItemSelected(item)
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    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="match_parent"
    android:background="#F8F8F8">

    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:background="?attr/colorPrimary"
        android:minHeight="?attr/actionBarSize"
        android:theme="?attr/actionBarTheme"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        android:elevation="4dp"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fontFamily="sans-serif"
        android:textSize="24sp"
        android:gravity="center" />

</androidx.constraintlayout.widget.ConstraintLayout>

Parent Theme

Theme.MaterialComponents.Light.NoActionBar

res/menu/toolbar_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_cut"
        android:title="Cut"
        app:showAsAction="always"
        android:icon="@drawable/ic_action_cut" />
    <item
        android:id="@+id/action_copy"
        android:title="Copy"
        app:showAsAction="always|withText"
        android:icon="@drawable/ic_action_copy" />
    <item
        android:id="@+id/action_paste"
        android:title="Paste"
        app:showAsAction="ifRoom"
        android:icon="@drawable/ic_action_paste" />
    <item
        android:id="@+id/action_new"
        android:title="New"
        app:showAsAction="never"
        android:icon="@drawable/ic_action_new" />
</menu>