FragmentStatePagerAdapter in Android

Overview

FragmentStatePagerAdapter is used to communicate between fragments. FragmentStatePagerAdapter is deprecated by the way.

Example of FragmentStatePagerAdapter

 <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">

    <androidx.viewpager.widget.ViewPager
            android:id="@+id/viewpager"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />

 </androidx.constraintlayout.widget.ConstraintLayout>

 class FragmentAdapter(private val fragmentManager : FragmentManager) :
    FragmentStatePagerAdapter(fragmentManager)
 {
    override fun getCount() : Int = 50

    override fun getItem(position : Int) : Fragment
    {
        val firstFragment = FirstFragment()
        val bundle = Bundle()
        bundle.putString("Message" , "Message from First Fragment $position")
        firstFragment.arguments = bundle
        return firstFragment
    }
 }

 class FirstFragment : Fragment()
 {
    override fun onCreateView(
        inflater : LayoutInflater , container : ViewGroup? , savedInstanceState : Bundle?
    ) : View?
    {
        return inflater.inflate(R.layout.fragment_first , container , false)
    }

    override fun onStart()
    {
        super.onStart()
        tvFirstFragmentLabel.text = arguments?.getString("Message")
    }
 }

 class MainActivity : AppCompatActivity()
 {
    private lateinit var fragmentAdapter : FragmentAdapter
    override fun onCreate(savedInstanceState : Bundle?)
    {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        fragmentAdapter = FragmentAdapter(supportFragmentManager)
        viewpager.adapter = fragmentAdapter
    }
 }

Reference

• https://github.com/iamraajkanchan/ViewPager_Android