Create An Android ViewSwitcher Programmatically in Kotlin

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

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

Output

Tutorialwing Kotlin Dynamic ViewSwitcher Output Android ViewSwitcher Programmatically in Kotlin

Tutorialwing Kotlin Dynamic ViewSwitcher Output

Getting Started

We can define android ViewSwitcher widget as below –

Android ViewSwitcher is a viewAnimator that are used to switch between two views. You may use viewFactory to create views or add your custom view to create views.

Now, how do we use ViewSwitcher 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 DynamicViewSwitcher. 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 ViewSwitcher 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 ViewSwitcher programmatically in kotlin. Please follow the steps below.

Download Drawable Resources Needed

We may need images, stored in res/drawable folder, that will be used in the application. These drawable images will be used by viewSwitcher while creating different views in the application.

2. Modify Values Folder

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

<resources>
    <string name="app_name">DynamicViewSwitcher</string>
    <string name="next">Next</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"?>
<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">

    <Button
        android:id="@+id/btnNext"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_margin="20dp"
        android:text="@string/next"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <LinearLayout
        android:id="@+id/rootContainer"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:orientation="vertical"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/btnNext">

    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

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

4. Create Android ViewSwitcher programmatically in Kotlin

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

package com.tutorialwing.dynamicviewswitcher

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.ViewGroup
import android.view.animation.AnimationUtils
import android.widget.ImageView
import android.widget.LinearLayout
import android.widget.ViewSwitcher
import com.tutorialwing.dynamicviewswitcher.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)

		setupViewSwitcher()
	}

	private fun setupViewSwitcher() {
		// Create ViewSwitcher Dynamically.
		val viewSwitcher = ViewSwitcher(this)
		val layoutParams = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		viewSwitcher.layoutParams = layoutParams

		val inAnim = AnimationUtils.loadAnimation(this, android.R.anim.slide_in_left)
		viewSwitcher.inAnimation = inAnim

		val out = AnimationUtils.loadAnimation(this, android.R.anim.slide_out_right)
		viewSwitcher.outAnimation = out

		val imageView1 = ImageView(this)
		val params1 = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		imageView1.layoutParams = params1
		imageView1.setImageResource(R.drawable.pomegranate)

		val imageView2 = ImageView(this)
		val params2 = LinearLayout.LayoutParams(
			ViewGroup.LayoutParams.WRAP_CONTENT,
			ViewGroup.LayoutParams.WRAP_CONTENT
		)
		imageView2.layoutParams = params2
		imageView2.setImageResource(R.drawable.zespri_kiwi)

		viewSwitcher.addView(imageView1)
		viewSwitcher.addView(imageView2)

		binding.rootContainer.addView(viewSwitcher)

		binding.btnNext.setOnClickListener { viewSwitcher.showNext() }
	}
}

In MainActivity.kt file, we have done below things –
a. We have created viewSwitcher dynamically. Then, we have set layout params in it. Then, we have set in and out animations in it.
b. After that, we have created two imageViews that will be added a child views to viewSwitcher widget.
c. Then, we have added this viewSwitcher into linearLayout having id rootContainer.

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

Tutorialwing Kotlin Dynamic ViewSwitcher Output Android ViewSwitcher Programmatically in Kotlin

Tutorialwing Kotlin Dynamic ViewSwitcher Output

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

Set Id of ViewSwitcher

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

    viewSwitcher.id = R.id.viewSwitcher_ID  // ViewSwitcher
    

    Here, we have set id of ViewSwitcher using property access syntax – viewSwitcher.id

Learn to Set ID of ViewSwitcher Using XML Attribute

Set Width and Height of ViewSwitcher

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

viewSwitcher.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 ViewSwitcher 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 ViewSwitcher Using XML Attribute

Set Padding of ViewSwitcher

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

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

Learn to Set Padding of ViewSwitcher Using XML Attribute

Set Margin of ViewSwitcher

Follow steps below to set margin of ViewSwitcher 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 ViewSwitcher 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)
    viewSwitcher.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 ViewSwitcher.

Learn to Set Margin of ViewSwitcher Using XML Attribute

Set Background of ViewSwitcher

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

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

Learn to Set Background of ViewSwitcher Using XML Attribute

Set Visibility of ViewSwitcher

We can set visibility of ViewSwitcher programmatically as –

viewSwitcher.visibility = View.VISIBLE

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

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

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