Android Check Box using kotlin example

1. Creating New Project in Kotlin

• Open Android Studio.
• Go to File => New => New Project.Give Name To your application. Then, check Include Kotlin Support and click next button.
• Select minimum SDK you need. However, we have selected 21 as minimum SDK. Then, click next button.
• Then, select Empty Activity => click next => click finish.

2.Here we take 2 Check box in our Layout android Provide Label Any fruit name. As in below xml layout.

     main_activity.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.dharmendra.checkbox.MainActivity">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentStart="true"
        android:layout_alignParentTop="true"
        android:gravity="center"
        android:textColor="@color/colorPrimary"
        android:layout_marginTop="47dp"
        android:textSize="25dp"
        android:text="Select Your Favourite Fruit"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:id="@+id/textView" />

    <CheckBox
        android:id="@+id/apple"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentStart="true"
        android:layout_below="@+id/textView"
        android:layout_marginStart="84dp"
        android:layout_marginTop="30dp"
        android:text="Apple" />

    <CheckBox
        android:id="@+id/mango"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignStart="@+id/apple"
        android:layout_below="@+id/apple"
        android:layout_marginTop="32dp"
        android:text="Mango" />


    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/mango"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="40dp"
        android:text="Click" />

</RelativeLayout>

3.MainActivity.kt

package com.dharmendra.checkbox

import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.widget.Button
import android.widget.CheckBox
import android.widget.Toast

class MainActivity : AppCompatActivity() {

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

        //Find View by id for checkBox and Button

        val apple = findViewById<CheckBox>(R.id.apple) as CheckBox
        val mango = findViewById<CheckBox>(R.id.mango) as CheckBox
        val btn = findViewById<Button>(R.id.button) as Button

        //Set onclick Of button

        btn.setOnClickListener {

            //Check Condition for all check box Checked or Not.


            if (mango.isChecked == true && apple.isChecked == true) {
                Toast.makeText(this@MainActivity, "Mango and Apple are Selected", Toast.LENGTH_LONG).show()
            } else if (apple.isChecked == true) {
                Toast.makeText(this@MainActivity, "Apple Selected", Toast.LENGTH_LONG).show()
            } else if (mango.isChecked == true) {
                Toast.makeText(this@MainActivity, "Mango Selected", Toast.LENGTH_LONG).show()
            } else {
                Toast.makeText(this@MainActivity, "Nothing is Selected", Toast.LENGTH_LONG).show()
            }
        }
    }
}

  Output: