In this article, we will learn about android CheckBox using Kotlin. We will go through various example that demonstrates how to use different attributes of CheckBox.

In this article, we will get answer to questions like –

• What is CheckBox?
• Why should we consider CheckBox while designing ui for any app?
• What are possibilities using CheckBox while designing ui? etc.

Let’s have a quick demo of things we want to cover in this tutorial –

Output

Tutorialwing Android Kotlin checkbox Output

Getting Started

We can define android CheckBox widget as below –

A checkbox is a specific type of two-states button that can be either checked or unchecked.

Now, how do we use CheckBox in android application ?

Creating New Project

At first, we will create an application.
So, follow steps below to create any android project in Kotlin –

Newbie in Android ?

Some very important concepts (Recommended to learn before you move ahead)

• Install Android Studio
• Create New Project in Android Studio
• Android Project Structure
• Run / Debug / Test Android App

Before we move ahead, we need to setup for viewBinding to access Android CheckBox Using Kotlin file without using findViewById() method.

Setup ViewBinding

Add viewBinding true in app/build.gradle file.

 
 android { 
 	// OTHER CODE... 
 	buildFeatures { 
 		viewBinding true 
 	} 
 } 
 

Now, set content in activity using view binding.
Open MainActivity.kt file and write below code in it.

 
 class MainActivity : AppCompatActivity() { 
 	
 	private lateinit var binding: ActivityMainBinding 
 	
 	override fun onCreate(savedInstanceState: Bundle?) { 
 		super.onCreate(savedInstanceState) 
 		binding = ActivityMainBinding.inflate(layoutInflater) 
 		val view = binding.root 
 		setContentView(view) 
 	} 
 } 
 

Now, we can access view in Kotlin file without using findViewById() method.

Using CheckBox in Kotlin

Follow steps below to use CheckBox in newly created project –

• Open res/layout/activity_main.xml file. Then, add below code in it –

  <?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"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      tools:context=".MainActivity">
  
      <CheckBox
          android:id="@+id/checkbox_ID"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:padding="10dp"
          android:text="@string/check_it"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toTopOf="parent" />
  
  </androidx.constraintlayout.widget.ConstraintLayout>
  

• We can also access it in Kotlin File, MainActivity.kt, as below –

  package com.tutorialwing.checkboxusingkotlin
  
  import androidx.appcompat.app.AppCompatActivity
  import android.os.Bundle
  import android.widget.Toast
  import com.tutorialwing.checkboxusingkotlin.databinding.ActivityMainBinding
  
  class MainActivity : AppCompatActivity() {
  
  	private lateinit var binding: ActivityMainBinding
  
  	override fun onCreate(savedInstanceState: Bundle?) {
  		super.onCreate(savedInstanceState)
  		binding = ActivityMainBinding.inflate(layoutInflater)
  		val view = binding.root
  		setContentView(view)
  
  		setCheckedChangedListener()
  	}
  
  	private fun setCheckedChangedListener() {
  		binding.checkboxID.setOnCheckedChangeListener { buttonView, isChecked ->
  			val msg = "You have " + if (isChecked) "checked" else "unchecked"
  			Toast.makeText(this@MainActivity, msg, Toast.LENGTH_SHORT).show()
  		}
  	}
  }
  

Now, run the application. We will get output as below –

Tutorialwing Android Kotlin checkbox Output

Different Attributes of CheckBox in XML

Now, we will see how to use different attributes of Android CheckBox using Kotlin to customise it –

Set Id of CheckBox

Many a time, we need id of View to access it in kotlin file or create ui relative to that view in xml file. So, we can set id of CheckBox using android:id attribute like below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        />

Here, we have set id of CheckBox as checkbox_ID using android:id=”” attribute. So, if we need to reference this CheckBox, we need to use this id – checkbox_ID.
Learn to Set ID of CheckBox Dynamically

Set Width of CheckBox

We use android:layout_width=”” attribute to set width of CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        />

Width can be either “MATCH_PARENT” or “WRAP_CONTENT” or any fixed value (like 20dp, 30dp etc.).
Learn to Set Width of CheckBox Dynamically

Set Height of CheckBox

We use android:layout_height=”” attribute to set height of CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        />

Height can be either “MATCH_PARENT” or “WRAP_CONTENT” or any fixed value.
Learn to Set Height of CheckBox Dynamically

Set Padding of CheckBox

We use android:padding=”” attribute to set padding of CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="10dp"
        />

Here, we have set padding of 10dp in CheckBox using android:padding=”” attribute.
Learn to Set Padding of CheckBox Dynamically

Set Margin of CheckBox

We use android:layout_margin=”” attribute to set margin of CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="10dp"
        />

Here, we have set margin of 10dp in CheckBox using android:layout_margin=”” attribute.
Learn to Set Margin of CheckBox Dynamically

Set Background of CheckBox

We use android:background=”” attribute to set background of CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:background="#ff0000"
        />

Here, we have set background of color #ff0000 in CheckBox using android:background=”” attribute.
Learn to Set Background of CheckBox Dynamically

Set Visibility of CheckBox

We use android:visibility=”” attribute to set visibility of CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:visibility="gone"
        />

Here, we have set visibility of CheckBox using android:visiblity=”” attribute. Visibility can be of three types – gone, visible and invisible
Learn to Set Visibility of CheckBox Dynamically

Set Text of CheckBox

We use android:text=”” attribute to set text of CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        />

Here, we have set text (“Hello Tutorialwing”) in CheckBox using android:text=”” attribute.
Similarly, we can set any text using this attribute.
Learn to Set Text of CheckBox Dynamically

Set Color of Text in CheckBox

We use android:textColor=”” attribute to set color of text in CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:textColor="#ffffff"     
        />

Here, we have set color (#ffffff i.e. white) of text (“Hello Tutorialwing”) in CheckBox using android:textColor=”” attribute. Similarly, we can set any color using this attribute.
Learn to Set Color of CheckBox Dynamically

Set Gravity of CheckBox

We use android:gravity=”” attribute to set gravity of text in CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:gravity="center_horizontal"
        />

Here, we have set gravity of text in CheckBox using android:gravity=”” attribute. Attribute value can be – “center_horizontal”, “center”, “center_vertical” etc.
Learn to Set Gravity of CheckBox Dynamically

Set Text in Uppercase, Lowercase

If we need to show text of CheckBox in uppercase or lowercase etc.

Set text in uppercase

We can use android:textAllCaps=”true” attribute to set text in uppercase. We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:textAllCaps="true"
        />

Attribute android:textAllCaps=”true” sets text in uppercase. So, HELLO TUTORIALWING is set in CheckBox.

By default, false is set in this attribute. So, Whatever value is written in android:text=”” attribute, it will be set as it is. For example,

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:textAllCaps="false"
        />

Above code will set Hello Tutorialwing to CheckBox.

How do we set text in lowercase?

Answer –

• In xml file – write all the text in lowercase.
• In kotlin file – take text as string. Then, convert it in lowercase. Then, set it to CheckBox.

Learn to Set Text in Uppercase or Lowercase Dynamically

Set Size of Text in CheckBox

We use android:textSize=”” attribute to set size of text in CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:textSize="20sp"
        />

Here, we have set size of text in CheckBox using android:textSize=”” attribute.
Learn to Set Size of Text of CheckBox Dynamically

Set Style (Bold/italic) of Text in CheckBox

We use android:textStyle=”” attribute to set style (bold, italic etc.) of text in CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:textStyle="bold"
        />

Here, we have set style of text in CheckBox using android:textStyle=”” attribute. This attribute can take bold, italic or normal.
Learn to Set Style of Text of CheckBox Dynamically

Set Letter Spacing of Text in CheckBox

We use android:letterSpacing=”” attribute to set spacing between letters of text in CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:letterSpacing="1"
        />

Here, we have set spacing between letters of text in CheckBox using android:letterSpacing=”” attribute.
Learn to Set Letter Spacing of Text of CheckBox Dynamically

Set Typeface of Text in CheckBox

We use android:typeface=”” attribute to set typeface in CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:typeface="sans"
        />

Here, we have set typeface of text in CheckBox using android:typeface=”” attribute. This attribute can take values – “sans”, “normal”, “monospace” or “normal”.
Learn to Set Typeface of CheckBox Dynamically

Set fontFamily of Text in CheckBox

We use android:fontFamily=”” attribute to set fontFamily of text in CheckBox.
We can do it as below –

    <CheckBox
        android:id="@+id/checkbox_ID"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello Tutorialwing"
        android:fontFamily="sans-serif"
        />

Here, we have set fontFamily (Here, sans-serif) of text in CheckBox using android:fontFamily=”sans-serif” attribute.

Till now, we have see how to use android CheckBox using Kotlin. We have also gone through different attributes of CheckBox to perform certain task. Let’s have a look at list of such attributes and it’s related task.

Different Attributes of Android CheckBox Widget

Below are the various attributes that are used to customise android CheckBox Widget. However, you can check the complete list of attributes of CheckBox in it’s official documentation site. Here, we are going to list some of the important attributes of this widget –

Attributes of checkbox are inherited from Textview, Compound Button and View. Some of the attributes inherited from Textview are –

Attributes of Checkbox inherited from Compound Button are –

Attributes of Checkbox inherited from View are –

We have seen different attributes of CheckBox and how to use it. If you wish to visit post to learn more about it

Thus, we have seen what is CheckBox, how can we use android CheckBox using Kotlin ? etc. We also went through different attributes of android CheckBox.