How to replace fragment in ViewPager2-CodePudding

I have migrated ViewPager to ViewPager2 and adapter FragmentPageAdapter to FragmentStateAdaper. In FragmentPageAdapter there is a method called getItemPostion(Object obj) by using this method I can able to replace fragments. In FragmentStateAdaper class that method is not there how to replace fragments in viewpager2 with FragmentStateAdaper.

CodePudding user response：

You have to override createFragment(position: Int) method in FragmentStateAdapter which returns Fragment for respective positions.

createFragment can be override like this

override fun createFragment(position: Int): Fragment {
      return when (position) {
            0 -> FragmentOne()
            1 -> FragmentTwo()
            else -> FragmentOne()
        }
}

Apart from this, you also have to override getItemCount() in FragmentStateAdapter, where you have to return total number of fragments.

CodePudding user response：

in your activity set viewpager

private fun setTabs() {
        listFragmentTitles = arrayListOf("Fragment1","Fragment2","Fragment3")
        viewPagerFragmentAdapter = 
        ViewPagerFragmentAdapter(this,listFragmentTitles)
        binding.viewPager.adapter = viewPagerFragmentAdapter
        TabLayoutMediator(
            binding.tabLayout, binding.viewPager
        ) { tab: TabLayout.Tab, position: Int ->
            tab.text = listFragmentTitles[position]
        }.attach()
    }

view pager adapter

internal class ViewPagerFragmentAdapter(
    fragmentActivity: FragmentActivity,
    listFragmentTitles: ArrayList<String>
) :
    FragmentStateAdapter(fragmentActivity) {

    val titlesList = listFragmentTitles

    override fun createFragment(position: Int): Fragment {
        when (position) {
            0 -> return Fragment1()
            1 -> return Fragment2()
            2 -> return Fragment3()
        }
        return Fragment1()
    }

    override fun getItemCount(): Int {
        return titlesList.size
    }
}