android kotlin - ActionBar title click listener

MainActivity.kt


package com.cfsuman.kotlintutorials

import android.graphics.Color
import android.os.Bundle
import android.view.Gravity
import android.widget.TextView
import androidx.appcompat.app.ActionBar.DISPLAY_SHOW_CUSTOM
import androidx.appcompat.app.AppCompatActivity
import androidx.constraintlayout.widget.ConstraintLayout.LayoutParams


class MainActivity : AppCompatActivity() {
    lateinit var context:MainActivity

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

        // Get the context
        context = this

        // Initialize a counter variable
        var counter = 0;


        // If the support action bar is available
        supportActionBar?.apply {
            // Show custom title in action bar
            customView = actionBarCustomTitle()


            // Action bar title click listener
            customView.setOnClickListener {
                counter++
                (it as TextView).text =
                    "Title clicked $counter time(s)"
            }


            // More action bar settings
            displayOptions = DISPLAY_SHOW_CUSTOM
            setDisplayShowHomeEnabled(true)
            setDisplayUseLogoEnabled(true)
            setLogo(R.drawable.ic_action_help)
        }
    }



    // Method to create a custom title for action bar
    private fun actionBarCustomTitle():TextView{
        return TextView(context).apply {
            // Set action bar title text
            text = "ActionBar Click Listener"


            // Initialize the layout params instance
            val params = LayoutParams(
                LayoutParams.MATCH_PARENT,
                LayoutParams.WRAP_CONTENT
            )

            // Apply the layout parameters to the text view
            layoutParams = params


            // Center align the text view/ action bar title
            gravity = Gravity.CENTER


            // Set the action bar title text appearance
            setTextAppearance(
                android.R.style
                    .TextAppearance_Material_Widget_ActionBar_Title
            )


            // Set the action bar title text color
            setTextColor(Color.WHITE)
        }
    }
}

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:id="@+id/rootLayout"
    android:background="#DCDCDC" />