MainActivity.kt
package com.cfsuman.kotlintutorials
import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.viewpager.widget.ViewPager
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// Get the widgets reference from XML layout
val viewPager = findViewById<ViewPager>(R.id.viewPager)
// Initialize a list of string values
val alphabets = listOf("a","b","c","d","e","f")
// Initialize a new pager adapter instance with list
val adapter = AlphabetPagerAdapter(alphabets)
// Finally, data bind the view pager widget with pager adapter
viewPager.adapter = adapter
}
}
activity_main.xml
<?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"
android:id="@+id/rootLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#DCDCDC"
android:padding="24dp">
<androidx.viewpager.widget.ViewPager
android:id="@+id/viewPager"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
page_layout.xml
<?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"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/tvColor"
android:layout_width="0dp"
android:layout_height="0dp"
android:fontFamily="sans-serif"
android:gravity="center"
android:textSize="250sp"
android:textStyle="bold"
app:layout_constraintBottom_toTopOf="@+id/tvFooter"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="@+id/tvFooter"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="end|bottom"
android:textSize="20sp"
android:textStyle="italic"
app:layout_constraintBottom_toBottomOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
AlphabetPagerAdapter.kt
package com.cfsuman.kotlintutorials
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.viewpager.widget.PagerAdapter
class AlphabetPagerAdapter(private val list: List<String>)
: PagerAdapter() {
override fun isViewFromObject(v: View, `object`: Any): Boolean {
// Return the current view
return v === `object` as View
}
override fun getCount(): Int {
// Count the items and return it
return list.size
}
override fun instantiateItem(
parent: ViewGroup, position: Int): Any {
// Get the view from pager page layout
val view = LayoutInflater.from(parent.context)
.inflate(R.layout.page_layout,parent,false)
// Get the widgets reference from layout
val tvColor: TextView = view.findViewById(R.id.tvColor)
val tvFooter: TextView = view.findViewById(R.id.tvFooter)
// Set the text views text
tvColor.text = list[position]
tvFooter.text = "Page ${position+1} of ${list.size}"
// Add the view to the parent
parent.addView(view)
// Return the view
return view
}
override fun destroyItem(
parent: ViewGroup, position: Int, `object`: Any) {
// Remove the view from view group specified position
parent.removeView(`object` as View)
}
}
