Create An Android Switch Programmatically in Kotlin

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

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

Output

Tutorialwing Android Dynamic Switch Output Android Switch programmatically in kotlin

Tutorialwing Android Dynamic Switch Output

Getting Started

We can define android Material Switch widget as below –

Android Switch is a two-state toggle widget that can select between two options (ON or OFF). The user can drag and drop thumb to select between two options or it can simply tap to toggle the state.

Now, how do we use Material Switch in android application ?

Creating New Project

Follow steps below to create any android project in Kotlin –

Step Description
1. Open Android Studio (Ignore if already done).
2. Go to File => New => New Project. This will open a new window. Then, under Phone and Tablet section, select Empty Activity. Then, click Next.
3. In next screen, select project name as DynamicSwitchMaterial. Then, fill other required details.
4. Then, clicking on Finish button creates new project.

Newbie in Android ?
Some very important concepts (Recommended to learn before you move ahead)

Before we move ahead, we need to setup for viewBinding to access Material Switch 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 Material Switch 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">DynamicSwitchMaterial</string>
    <string name="off">OFF</string>
    <string name="on">ON</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 Material Switch Dynamically and add it into this LinearLayout having id rootContainer.

4. Create Android Material Switch programmatically in Kotlin

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

package com.tutorialwing.dynamicswitchmaterial

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.ViewGroup
import android.widget.LinearLayout
import android.widget.Toast
import com.google.android.material.switchmaterial.SwitchMaterial
import com.tutorialwing.dynamicswitchmaterial.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)

		setupSwitch()
	}

	private fun setupSwitch() {
		// Create Switch programmatically.
		val sw = SwitchMaterial(this)
		val layoutParams = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		layoutParams.setMargins(30, 30, 30, 30)
		sw.layoutParams = layoutParams
		sw.text = getString(R.string.off)

		// Add Switch to LinearLayout
		binding.rootContainer.addView(sw)

		sw.setOnCheckedChangeListener { _, isChecked ->
			val msg = getString(if (isChecked) R.string.on else R.string.off)
			Toast.makeText(this@MainActivity, msg, Toast.LENGTH_SHORT).show()
			sw.text = msg
		}
	}
}

In MainActivity.kt file, we have created Switch programmatically in kotlin in the application. Then, we have set layout params, margin and text to the Switch widget. At last, we have set checked change listener to show text as toast whenever there is change in the checked state of the Switch widget.

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

Tutorialwing Android Dynamic Switch Output Android Switch programmatically in kotlin

Tutorialwing Android Dynamic Switch Output

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

Set Id of Material Switch

Follow steps below to set id of Material Switch 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="materialSwitch_ID" />
    </resources>
    
  • Now, we can set id of Material Switch dynamically, in MainActivity.kt file, as –

    materialSwitchID.id = R.id.materialSwitch_ID  // Material Switch
    

    Here, we have set id of Material Switch using property access syntax – materialSwitchID.id

Learn to Set ID of Material Switch Using XML Attribute

Set Width and Height of Material Switch

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

materialSwitchID.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 Material Switch 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 Material Switch Using XML Attribute

Set Padding of Material Switch

Follow steps below to set padding of Material Switch 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 Material Switch dynamically, in MainActivity.kt file, as –
    val padding = resources.getDimension(R.dimen.text_padding).toInt()
    materialSwitchID.setPadding(padding, padding, padding, padding)
    

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

Learn to Set Padding of Material Switch Using XML Attribute

Set Margin of Material Switch

Follow steps below to set margin of Material Switch 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 Material Switch 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)
    materialSwitchID.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 Material Switch.

Learn to Set Margin of Material Switch Using XML Attribute

Set Background of Material Switch

Follow steps below to set background of Material Switch 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 Material Switch dynamically, in MainActivity.kt file, as –
    val color = ContextCompat.getColor(this, R.color.purple_200)
    materialSwitchID.setBackgroundColor(color)
    

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

Learn to Set Background of Material Switch Using XML Attribute

Set Visibility of Material Switch

We can set visibility of Material Switch programmatically as –

materialSwitchID.visibility = View.VISIBLE

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

Set Text of Material Switch

Follow steps below to set text of Material Switch programmatically –

  • If there is no strings.xml file, create strings.xml file in res/values folder. Then, add below code in it –
    <resources>
        <string name="click_on_me">Click on me</string>
    </resources>
    
  • Now, we can set text of Material Switch dynamically, in MainActivity.kt file, as –
    materialSwitchID.text = getString(R.string.click_on_me)
    

    Here, we used materialSwitchID.text to set text in materialSwitchID.

Learn to Set Text of Material Switch Using XML Attribute

Set Color of Text of Material Switch

Follow steps below to set color of text of Material Switch programmatically in Kotlin –

  • 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="black">#FF000000</color>
    </resources>
    
  • Now, we can set color of text of Material Switch dynamically, in MainActivity.kt file, as –
    val textColor = ContextCompat.getColor(this, R.color.black)
    materialSwitchID.setTextColor(textColor)
    

    Here, we used setTextColor() method to set color of Material Switch of materialSwitchID.

Learn to Set Color of Material Switch Using XML Attribute

Set Gravity of Material Switch

We can set gravity of text of Material Switch programmatically in Kotlin as –

materialSwitchID.gravity = Gravity.CENTER

Here, we have set gravity of Material Switch as center. So, all the text of Material Switch will be center aligned.
We can also apply multiple gravity values as –

materialSwitchID.gravity = Gravity.CENTER_HORIZONTAL or Gravity.BOTTOM

Here, we have applied multiple gravity values, in Kotlin, to Material Switch. In above case, text will be aligned as horizontally centered to bottom.
Learn to Set Margin of Material Switch Using XML Attribute

Set Text in Uppercase or Lowercase

Follow steps below to set text in uppercase or lowercase programmatically as –

  • Set Text in Uppercase

    We use materialSwitchID.isAllCaps attributes to set text in uppercase or normal. If it is true, text will be set in uppercase.

    materialSwitchID.text = "Hello Tutorialwing"
    materialSwitchID.isAllCaps = true
    

    In Above case, “Hello Tutorialwing” will be set in Uppercase to Material Switch. So, text will be “HELLO TUTORIALWING”.

  • By default, isAllCaps is false. So, whatever is written, text will be set as it is. For example,

    materialSwitchID.text = "Hello Tutorialwing"
    materialSwitchID.isAllCaps = false. // By default it is false. Written here for example.
    

    Above code will set text, “Hello Tutorialwing”, to Material Switch without changing it to Uppercase.

    Actually, if isAllCaps is false, text is set as it is. It neither changes to uppercase nor lowercase.

    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 materialSwitchID.

Learn to Set Text in Uppercase or Lowercase Using XML Attribute

Set Size of Text in Material Switch

Follow steps below to set size of Material Switch programmatically using materialSwitchID.textSize attribute –

  • Open res/values/dimens.xml file. Then, add below font-size in it –
    <dimen name="text_size">16sp</dimen>
    
  • Now, using materialSwitchID.textSize attribute, we can set size of text dynamically as –

    materialSwitchID.textSize = resources.getDimension(R.dimen.text_margin)
    

Learn to Set Size of Text in Material Switch Using XML Attribute

Set Style (Bold/italic) of Text in Material Switch

We can set textStyle of Material Switch programmatically as –

materialSwitchID.typeface = Typeface.DEFAULT_BOLD;

In above case, we have set textStyle as bold. So, text of Material Switch will be displayed as bold letters.

If we want to preserve previous textStyle too, we can do it as –

materialSwitchID.setTypeface(materialSwitchID.typeface, Typeface.BOLD);

Learn to Set Typeface of Material Switch Using XML Attribute

Set Letter Spacing of Text in Material Switch

Follow steps below to set letter spacing of Material Switch programmatically –

  • Open res/values/dimens.xml file. Then, add below dimension in it –
    <dimen name="text_letter_spacing">1dp</dimen>
    
  • We use materialSwitchID.letterSpacing attribute to set letter spacing of Material Switch as below –

    materialSwitchID.letterSpacing = resources.getDimension(R.dimen.text_letter_spacing)
    

Learn to Set Letter Spacing of Material Switch Using XML Attribute

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

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