android - Pass data from Activity to Fragment in ViewPager

Question

I have a simple Activity with TabLayout, ViewPager and 2 Fragments in it. Here\'s my Activity:

public class ManagementCompanyOverviewActivity extends BaseAct         


        

Answer 1

Fragment

class SampleFragment : Fragment(), BaseFragmentInteraction {
    override fun updateFragmentData(data: String) {
        Toast.makeText(activity!!, data, Toast.LENGTH_SHORT).show()
    }
}

Interface

interface BaseFragmentInteraction {
    fun updateFragmentData(data: String)
}

Activity:

view_pager.addOnPageChangeListener(object : ViewPager.OnPageChangeListener {

        override fun onPageSelected(position: Int) {
            val fragmentItem = (view_pager.adapter as FragmentPagerAdapter).getItem(view_pager.currentItem)
            (fragmentItem as BaseFragmentInteraction).updateFragmentData("SomeData")
        }

        override fun onPageScrollStateChanged(state: Int) {}

        override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {}
    })

The updateFragmetData method will be called in the current selected viewpager item fragment. You can also add a tag parameter to updateFragmetData so that you can be sure the right fragment instance is called. If required you can call isVisible in updateFragmetData implementation to make sure the fragment is visible.