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

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

Output

Tutorialwing Kotlin Dynamic ViewAnimator Output

Getting Started

We can define android ViewAnimator widget as below –

ViewAnimator is a widget that are used to switch between views using animations.

Now, how do we use ViewAnimator in android application ?

Before we move ahead, we need to setup for viewBinding to access ViewAnimator 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 ViewAnimator 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">DynamicViewAnimator</string>
    <string name="next">Next</string>
    <string name="prev">Previous</string>
    <string name="item_post_1">Text at position 1</string>
    <string name="item_post_2">Button at position 2</string>
    <string name="item_post_4">Text at positon 4</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 xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:orientation="horizontal"
        android:padding="10dp">

        <Button
            android:id="@+id/buttonPrev"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/prev" />

        <Button
            android:id="@+id/buttonNext"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="15dp"
            android:text="@string/next" />

    </LinearLayout>

    <LinearLayout
        android:id="@+id/rootContainer"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

    </LinearLayout>

</LinearLayout>

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

4. Create Android ViewAnimator programmatically in Kotlin

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

package com.tutorialwing.dynamicviewanimator

import android.graphics.Color
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.ViewGroup
import android.view.animation.AnimationUtils
import android.widget.*
import com.tutorialwing.dynamicviewanimator.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)

		setupViewAnimator()
	}

	private fun setupViewAnimator() {
		val viewAnimator = ViewAnimator(this)
		val layoutParams = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.MATCH_PARENT,
			ViewGroup.LayoutParams.MATCH_PARENT
		)
		layoutParams.setMargins(30, 30, 30, 30)
		viewAnimator.layoutParams = layoutParams

		val animationIn = AnimationUtils.loadAnimation(this, android.R.anim.slide_in_left)
		val animationOut = AnimationUtils.loadAnimation(this, android.R.anim.slide_out_right)

		viewAnimator.inAnimation = animationIn
		viewAnimator.outAnimation = animationOut

		val textView = TextView(this)
		val textParams = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		textView.layoutParams = textParams
		textView.text = getString(R.string.item_post_1)
		textView.setTextColor(Color.RED)
		viewAnimator.addView(textView)

		val button = Button(this)
		val buttonParams = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		button.layoutParams = buttonParams
		button.text = getString(R.string.item_post_2)
		button.setTextColor(Color.RED)
		viewAnimator.addView(button)

		val imageView = ImageView(this)
		val imageParams = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		imageView.layoutParams = imageParams
		imageView.setImageResource(R.mipmap.ic_launcher)
		viewAnimator.addView(imageView)

		val textView2 = TextView(this)
		val textParams2 = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		textView2.layoutParams = textParams2
		textView2.text = getString(R.string.item_post_4)
		textView2.setTextColor(Color.RED)
		viewAnimator.addView(textView2)

		binding.rootContainer.addView(viewAnimator)

		binding.buttonPrev.setOnClickListener { viewAnimator.showPrevious() }
		binding.buttonNext.setOnClickListener { viewAnimator.showNext() }
	}
}

We have created viewAnimator programmatically in kotlin file( i.e. in MainActivity.kt file) in the application. Then, we have set layout params, margins etc. in it. Then, we have created child views for viewAnimator. They are TextView, Button, ImageView and TextView respectively. Each one of them have been added to viewAnimator. Then, we have added this viewAnimator in linearLayout having id rootContainer. Then, we have added click listener on prev and next buttons to show previous and next view in viewAnimator respectively.

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

Tutorialwing Kotlin Dynamic ViewAnimator Output

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

Set Id of ViewAnimator

Follow steps below to set id of ViewAnimator 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="viewAnimator_ID" />
  </resources>
  

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

  viewAnimator.id = R.id.viewAnimator_ID  // ViewAnimator
  

  Here, we have set id of ViewAnimator using property access syntax – viewAnimator.id

Learn to Set ID of ViewAnimator Using XML Attribute

Set Width and Height of ViewAnimator

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

viewAnimator.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 ViewAnimator 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 ViewAnimator Using XML Attribute

Set Padding of ViewAnimator

Follow steps below to set padding of ViewAnimator 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 ViewAnimator dynamically, in MainActivity.kt file, as –

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

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

Learn to Set Padding of ViewAnimator Using XML Attribute

Set Margin of ViewAnimator

Follow steps below to set margin of ViewAnimator 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 ViewAnimator 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)
  viewAnimator.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 ViewAnimator.

Learn to Set Margin of ViewAnimator Using XML Attribute

Set Background of ViewAnimator

Follow steps below to set background of ViewAnimator 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 ViewAnimator dynamically, in MainActivity.kt file, as –

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

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

Learn to Set Background of ViewAnimator Using XML Attribute

Set Visibility of ViewAnimator

We can set visibility of ViewAnimator programmatically as –

viewAnimator.visibility = View.VISIBLE

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

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