In this article, we will learn how to create android CalendarView programmatically in Kotlin. We will go through various steps that explains how to create CalendarView and add it in kotlin file, use different attributes to customise it etc. in any android application. For example, how to set text in CalendarView programmatically, how to set id of CalendarView, how to capitalise text of CalendarView dynamically etc. We will get answer to all such questions in this post.

Learn to use Different Attributes of CalendarView in XML File to Customize it.

Output

Tutorialwing Android Kotlin Dynamic CalendarView Output

Getting Started

We can define android CalendarView widget as below –

CalendarView is a widget that are used to display and select date.

Now, how do we use CalendarView in android application ?

Before we move ahead, we need to setup for viewBinding to access CalendarView in 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.

Since we have a new project, we will modify the xml and class file to use CalendarView programmatically in kotlin. Please follow the steps below.

2. Modify Values Folder

Open res/values/strings.xml file. Add below code into it.

<resources>
    <string name="app_name">DynamicCalendarView</string>
</resources>

Other values folders have not been changed. So, we are not going to mention it here.

3. Modify Layout Folder

Open res/layout/activity_main.xml file. Add below code into it.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:id="@+id/rootContainer"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:orientation="vertical">

</LinearLayout>

Note that LinearLayout has id rootContainer. In Kotlin file, we will create CalendarView Dynamically and add it into this LinearLayout having id rootContainer.

4. Create Android CalendarView programmatically in Kotlin

Open src/main/java/com.tutorialwing.dynamiccalendarview/MainActivity.kt file. Then, add below code into it.

package com.tutorialwing.dynamiccalendarview

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.ViewGroup
import android.widget.CalendarView
import android.widget.LinearLayout
import android.widget.Toast
import com.tutorialwing.dynamiccalendarview.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)

		setupCalendar()
	}

	private fun setupCalendar() {
		val calendarView = CalendarView(this)
		val layoutParams = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		layoutParams.setMargins(90, 40, 80, 40)
		calendarView.layoutParams = layoutParams

		calendarView.setOnDateChangeListener { view, year, month, dayOfMonth ->
			// Note that months are indexed from 0. So, 0 means january, 1 means February, 2 means march etc.
			val msg = "Selected date is " + dayOfMonth + "/" + (month + 1) + "/" + year
			Toast.makeText(this@MainActivity, msg, Toast.LENGTH_SHORT).show()
		}

		binding.rootContainer.addView(calendarView)
	}
}

We have created CalendarView programmatically in kotlin file (i.e. MainActivity.kt file) in the application. After that, we have set layout params, margins etc. in it. After that, we have set date change listener in calendarView that display selected date as toast message whenever there is any change in date selection in the calendarView. At last, we have added this calendarView widget in linearLayout having id rootContainer.

Finally, when you run the application, you will get output as shown above.

Tutorialwing Android Kotlin Dynamic CalendarView Output

Now, Let’s check how to use different attributes of CalendarView to customize it dynamically –

Set Id of CalendarView

Follow steps below to set id of CalendarView programmatically –

• Create ids.xml file in res/values folder. Then, add below code into it –

  <?xml version="1.0" encoding="utf-8"?>
  <resources>
      <item type="id" name="calendarView_ID" />
  </resources>
  

• Now, we can set id of CalendarView dynamically, in MainActivity.kt file, as –

  calendarView.id = R.id.calendarView_ID  // CalendarView
  

  Here, we have set id of CalendarView using property access syntax – calendarView.id

Learn to Set ID of CalendarView Using XML Attribute

Set Width and Height of CalendarView

We use layoutParams to set width and height of any View programmatically. In this article, we have added CalendarView in LinearLayout. So, we will define LayoutParams as below –

calendarView.layoutParams = LinearLayout.LayoutParams(
	ViewGroup.LayoutParams.WRAP_CONTENT,
	ViewGroup.LayoutParams.WRAP_CONTENT
)

Here, we have set width and height as WRAP_CONTENT. Some of possible values for width and height are –

• WRAP_CONTENT: Sets value of width or height depending on text inside it.
• MATCH_PARENT: Sets value of width of height depending on width or height of parent layout . i.e. width or height of CalendarView will be same as width or height of parent layout.
• Fixed Value: Sets width or height as per value provided.

Learn to Set Width or Height of CalendarView Using XML Attribute

Set Padding of CalendarView

Follow steps below to set padding of CalendarView Dynamically –

• If there is no dimens.xml file, create dimens.xml file in res/values folder. Then, add below code in it –

  <?xml version="1.0" encoding="utf-8"?>
  <resources>
      <dimen name="text_padding">16dp</dimen>
  </resources>
  

• Now, we can set padding of CalendarView dynamically, in MainActivity.kt file, as –

  val padding = resources.getDimension(R.dimen.text_padding).toInt()
  calendarView.setPadding(padding, padding, padding, padding)
  

  Here, we have accessed dimension defined in dimens.xml using getDimension() method. Then, set padding of CalendarView using setPadding() method.

Learn to Set Padding of CalendarView Using XML Attribute

Set Margin of CalendarView

Follow steps below to set margin of CalendarView Dynamically –

• If there is no dimens.xml file, create dimens.xml file in res/values folder. Then, add below code in it –

  <?xml version="1.0" encoding="utf-8"?>
  <resources>
      <dimen name="text_margin">16dp</dimen>
  </resources>
  

• Now, we can set margin of CalendarView dynamically, in MainActivity.kt file, as –

  val margin = resources.getDimension(R.dimen.text_margin).toInt()
  val layoutParams = LinearLayout.LayoutParams(
  	ViewGroup.LayoutParams.WRAP_CONTENT,
  	ViewGroup.LayoutParams.WRAP_CONTENT
  )
  layoutParams.setMargins(margin, margin, margin, margin)
  calendarView.layoutParams = layoutParams
  

  Here, we have accessed dimension defined in dimens.xml using getDimension() method. Then, we have defined layoutParams, set margin to layoutParams. After that, set layoutParams to CalendarView.

Learn to Set Margin of CalendarView Using XML Attribute

Set Background of CalendarView

Follow steps below to set background of CalendarView programmatically –

• If there is no colors.xml file, create colors.xml file in res/values folder. Then, add below code in it –

  <?xml version="1.0" encoding="utf-8"?>
  <resources>
      <color name="purple_200">#FFBB86FC</color>
  </resources>
  

• Now, we can set background of CalendarView dynamically, in MainActivity.kt file, as –

  val color = ContextCompat.getColor(this, R.color.purple_200)
  calendarView.setBackgroundColor(color)
  

  Here, we used setBackgroundColor() method to set background color in calendarView.

Learn to Set Background of CalendarView Using XML Attribute

Set Visibility of CalendarView

We can set visibility of CalendarView programmatically as –

calendarView.visibility = View.VISIBLE

Here, we have set visibility of CalendarView using calendarView.visibility attribute. Visibility can be of three types – gone, visible and invisible.
Learn to Set Visibility of CalendarView Using XML Attribute

That’s end of tutorial on CalendarView Programmatically in Kotlin With Example.