Create a Switch in Kotlin Programmatically

In this short Kotlin programming tutorial we will learn how to create a Switch in Kotlin programmatically. In the code example below we are going to cover:

Create Switch and add it to a LinearLayout
Get input from the Switch when it’s state is changed
Set textOff and textOn text programmatically
Set OnClickListener on the Switch so that we can handle state changes event

Activity XML Layout File

Following is the Activity_switch_example.xml containing an empty LinearLayout to which we will add the Switch.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/linearLayout"
    android:orientation="vertical"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
  tools:context="com.appsdeveloperblog.kotlinexample3.SwitchExample">
</LinearLayout>

Switch UI Component Example in Kotlin

Below is Kotlin code example which demonstrates how to create and add a Switch UI component to our app activity programmatically. It also shows how to set onClickListener and handle events when user taps on the Switch component to change its state from On to Off and back from Off to On.

package com.appsdeveloperblog.kotlinexample3

import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.widget.LinearLayout
import android.widget.Switch

class SwitchExample : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_switch_example)
        val linearLayout = findViewById(R.id.linearLayout) as LinearLayout

        val switch = Switch(this)
        switch.textOn = "Switch is on"
        switch.textOff = "Switch is off"
        switch.text = "switch is "+ switch.isChecked
        switch.setOnClickListener(View.OnClickListener {
            switch.text = "switch is "+ switch.isChecked
        })

        linearLayout.addView(switch)
    }
}

If you run the above code example in Android studio you should the the following view:

Create Switch in Kotlin