Develop Reference

BrowseSupportFragment(Leanback): manually select mainfragment

I am building app for android tv but having issue on manually selecting main fragment. I want click on header item to change main fragment rather than changing on focus using fragment factory.
Code
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
isHeadersTransitionOnBackEnabled = true
val listRowPresenter = ListRowPresenter(FocusHighlight.ZOOM_FACTOR_SMALL)
mRowsAdapter = ArrayObjectAdapter(listRowPresenter)
adapter = mRowsAdapter
mainFragmentRegistry.registerFragment(PageRow::class.java, PageRowFragmentFactory())
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
loadData()
headersSupportFragment.setOnHeaderViewSelectedListener { viewHolder, row ->
//Only Focus View. Don't change main fragment
}
headersSupportFragment.setOnHeaderClickedListener { viewHolder, row ->
//Change main fragment here
//No documentation provided what to write here
}
}
fun loadData() {
val headerItem1 = HeaderItem(1, "HEADER_NAME_1")
val pageRow1 = PageRow(headerItem1)
mRowsAdapter.add(pageRow1)
val headerItem2 = HeaderItem(2, "HEADER_NAME_2")
val pageRow2 = PageRow(headerItem2)
mRowsAdapter.add(pageRow2)
}
Factory
private class PageRowFragmentFactory : BrowseSupportFragment.FragmentFactory<Fragment>() {
override fun createFragment(rowObj: Any?): Fragment {
val row = rowObj as Row
return when (row.headerItem.id) {
1L -> SampleFragmentA()
2L -> SampleFragmentB()
else -> throw IllegalArgumentException(String.format("Invalid row %s", rowObj))
}
}
}

Passing adapter text to fragment creating problems

I want to pass data to fragment so when items in recycler adapter clicked it pass item name (sample[position].text1) fetched from firebase to fragment. I tried bundle, interface but getting error in both methods.I searched on internet but not find anything which solve my problem. mainActivity(splash screen) is only Activity in my App rest are fragments.
I used inner class method, I'm getting result but in another fragment where this adapter attached and I don't want it there.
Problem: pass sample[position].text1 to fragment so I can pass it to db.collection("here") to fetch data from Firebase.
Adapter
class dashboard_gridlayout_adapter(
private val sampledata: ArrayList<daxhboard_gridlayout_data>
): Adapter<dashboard_gridlayout_adapter.dashboard_viewholder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): dashboard_viewholder {
val itemView = LayoutInflater.from(parent.context).inflate(R.layout.dashboard_gridlayout_single_item_design, parent, false)
return dashboard_viewholder(itemView)
}
override fun onBindViewHolder(holder: dashboard_viewholder, position: Int) {
Glide.with(holder.itemView).load(sampledata[position].imageResource)
.placeholder(R.drawable.ic_baseline_history_icon)
.into(holder.imageView)
holder.textView.text = sampledata[position].text1
holder.itemView.setOnClickListener {
val appCompatActivity = it.context as AppCompatActivity
appCompatActivity.supportFragmentManager.beginTransaction()
.replace(R.id.Activity_frag_container, service_providers_list())
.addToBackStack(null)
.commit()
}
}
override fun getItemCount() = sampledata.size
inner class dashboard_viewholder(itemView: View) : RecyclerView.ViewHolder(itemView) {
val imageView: ImageView = itemView.dashboard_adapter_image
val textView: TextView = itemView.dashboard_adapter_text
}
}
Fragment
class service_providers_list : Fragment(){
private var db = FirebaseFirestore.getInstance()
private lateinit var service_list_recycler: RecyclerView
var servlist = ArrayList<service_provider_list_data>()
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.service_providers_list, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
getserviceproviderdata()
service_list_recycler = service_provider_recycle_view.findViewById(R.id.service_provider_recycle_view)
service_provider_recycle_view.layoutManager = LinearLayoutManager(this.requireContext())
service_provider_recycle_view.setHasFixedSize(true)
}
private fun getserviceproviderdata() {
db.collection("Barber").orderBy("dist")
.get()
.addOnSuccessListener { documents ->
servlist.clear()
for (document in documents) {
val imgurl = document.data["imageResource"].toString()
val prov_name = document.data["provider_name"].toString()
val prov_address = document.data["provider_address"].toString()
val prov_rate = document.data["provider_rating"].toString()
val prov_dist = document.data["provider_distance"].toString()
servlist.add(service_provider_list_data(imgurl, prov_name, prov_address, prov_rate, prov_dist))
service_provider_recycle_view.adapter = service_provider_list_adapter(servlist)
}
}
.addOnFailureListener { exception ->
Log.e("serf", "Error getting documents: ", exception)
}
}
}
MainActivity (It's a splash screen)
class MainActivity : AppCompatActivity(){
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
#Suppress("DEPRECATION")
Handler().postDelayed(
{
supportFragmentManager.beginTransaction().replace(R.id.Activity_frag_container,Login_Screen()).commit()
},
1500
)
}
}

I solved this problem
just add new parameter(need to pass) inside replace in adapter
holder.itemView.setOnClickListener {
val datashares = sampledata[position].text1
val appCompatActivity = it.context as AppCompatActivity
appCompatActivity.supportFragmentManager.beginTransaction()
.replace(R.id.Activity_frag_container, service_providers_list(datashares))
.addToBackStack(null)
.commit()
}
and inside fragment just add
class service_providers_list(datashares: String) Fragment(){
//variable declaration
private var datasharae = datashares
(inside function where i wnt to add code i.e getserviceproviderdata() )
fun getserviceproviderdata() {
db.collection(datasharae)
.............
..............
......rest code.....
.........}

When I press the back button or make the gesture to go back, it does not reload the ViewPager properly

I'm using Navigation Component, although I don't think that's the problem. The thing is that when I'm in a fragment that contains a ViewPager and I navigate to another one, when I go back using the back button or the gesture of the mobile phone, it returns to the previous fragment but it stops showing the ViewPager. I'll leave you my code for that fragment:
class HomeFragment : Fragment() {
private lateinit var homeFragmentViewModel: HomeFragmentViewModel
private var listAdapter: FlagsListAdapter? = null
private var regionName: String? = null
private val hashtagLabel: TextView by lazy { home_fragment__label__hashtag }
private val flagViewPager: ViewPager by lazy { home_fragment__viewpager__countries }
private val countryLabel: TextView by lazy { home_fragment__label__country_name }
private val showCasesButton: Button by lazy { home_fragment__button__country_cases }
companion object {
fun newInstance(): HomeFragment {
return HomeFragment()
}
}
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
return inflater.inflate(R.layout.fragment_home, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
homeFragmentViewModel = ViewModelProvider(this).get(HomeFragmentViewModel::class.java)
homeFragmentViewModel.getCountriesFlagLiveData().observeOnce(viewLifecycleOwner, Observer {
setFlagsAdapter(it)
})
showCasesButton.setOnClickListener {
val actionNavigateToShowCasesFragment = HomeFragmentDirections.navigateHomeFragmentToShowCasesFragment()
regionName?.let { regionName -> actionNavigateToShowCasesFragment.regionName = regionName }
it.findNavController().navigate(actionNavigateToShowCasesFragment)
}
setFormatHashtag()
}
private fun setFlagsAdapter(flagModelList: List<FlagModel>) {
listAdapter = context?.let {
FlagsListAdapter(
flagModelList,
it
)
}
flagViewPager.adapter = listAdapter
flagViewPager.setPadding(130, 0, 130, 0)
flagViewPager.addOnPageChangeListener(object : ViewPager.OnPageChangeListener {
override fun onPageScrollStateChanged(state: Int) {
Toast.makeText(GlobalApplication.getContextFromApplication, "Hola", Toast.LENGTH_SHORT).show()
}
override fun onPageScrolled(
position: Int,
positionOffset: Float,
positionOffsetPixels: Int
) {
countryLabel.text = ""
countryLabel.text = flagModelList[position].regionName
regionName = flagModelList[position].regionName
}
override fun onPageSelected(position: Int) {
countryLabel.text = flagModelList[position].regionName }
})
}
private fun setFormatHashtag() {
val text = getString(R.string.home_fragment_hashtag)
val spannableString = SpannableString(text)
val foregroundColorSpan = context?.let {
ForegroundColorSpan(ContextCompat.getColor(it, R.color.hashtagColor))
}
spannableString.setSpan(foregroundColorSpan, 0, 8, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)
hashtagLabel.text = spannableString
}
}
This is my activity:
class MainActivity : AppCompatActivity() {
private val navigationBottomBar by lazy { activity_main__navigation_view__bottom_bar }
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
setUpNavigation()
}
private fun setUpNavigation() {
val navController = Navigation.findNavController(this, R.id.activity_main__graph__nav_host)
NavigationUI.setupWithNavController(navigationBottomBar, navController)
}
}
When you load the fragment the first time it is shown like this, which is how it should be shown, and if I use the Bottom Navigation View it does well too:
But when I use the back button on my phone, here's what happens:

The problem is in your HomeFragment,setFlagsAdapter(it)` doesn't get called when you come back to this fragment. Either
change observeOnce to observe
or
Move
homeFragmentViewModel.getCountriesFlagLiveData().observeOnce(viewLifecycleOwner, Observer {
setFlagsAdapter(it)
})
from onCreateView to
override fun onResume(){
super.onResume()
homeFragmentViewModel.getCountriesFlagLiveData().observeOnce(viewLifecycleOwner, Observer {
setFlagsAdapter(it)
})
}

How to properly map shared element transition from RecyclerView to ViewPager dynamically?

I have an activity that hosts both fragments called SourceFragment and DestinationFragment. The SourceFragment contains a RecyclerView and the DestinationFragment contains a ViewPager. I've been using the fragment manager to swap back and forth between the Source and Destination fragment.
Issue:
The return transition works normally as long as I don't swipe to a different view on the ViewPager. To resolve this I overrode the onMapSharedElements in the DestinationFragment and the SourceFragment to make sure the views match each other when the view pager is swiped.
For some reason swiping and returning to the SourceFragment doesn't work and no transition animation happens. I even debugged the onMapSharedElements functions to make sure that the views mapped correctly.
This is what I'm trying to implement.
My implementation
I've provided the code below for the fragments in question but here is the repo to my implementation. Been itching my head for a week now trying to figure this out hopefully I can get some insight as to why this is happening.
SourceFragment:
class SourceFragment : Fragment() {
private lateinit var sharedViewModel: SharedViewModel
private lateinit var itemRecyclerView: RecyclerView
private lateinit var adapter: SourceAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setExitSharedElementCallback(object : SharedElementCallback() {
override fun onMapSharedElements(names: MutableList<String>?, sharedElements: MutableMap<String, View>?) {
val view = itemRecyclerView.findViewHolderForAdapterPosition(sharedViewModel.currentPos)
?.itemView?.findViewById<TextView>(R.id.source_text)
val item = sharedViewModel.itemList[sharedViewModel.currentPos]
if (view == null) return
names?.clear()
sharedElements?.clear()
names?.add(item)
sharedElements?.put(item, view)
}
})
sharedViewModel = ViewModelProviders.of(requireActivity()).get(SharedViewModel::class.java)
adapter = SourceAdapter(object : onClickItem {
override fun onClick(position: Int, view: View) {
// Save the position of the item that was clicked.
sharedViewModel.currentPos = position
// Setup shared element transition
val transitionName = ViewCompat.getTransitionName(view) ?: ""
// Start fragment transaction along with shared element transition.
fragmentManager?.apply {
beginTransaction()
.setReorderingAllowed(true)
.addSharedElement(view, transitionName)
.replace(
R.id.fragment_container,
DestinationFragment(),
DestinationFragment::class.java.simpleName
)
.addToBackStack(null)
.commit()
}
}
})
val list = sharedViewModel.itemList
adapter.submitList(list)
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val view = inflater.inflate(R.layout.source_layout, container, false)
postponeEnterTransition()
return view
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
// Setup recycler view here
itemRecyclerView = item_recycler_view
itemRecyclerView.layoutManager = GridLayoutManager(requireContext(), 2)
itemRecyclerView.adapter = adapter
// Start enter transition on pre draw.
itemRecyclerView.viewTreeObserver.addOnPreDrawListener(object : ViewTreeObserver.OnPreDrawListener {
override fun onPreDraw(): Boolean {
itemRecyclerView.viewTreeObserver.removeOnPreDrawListener(this)
startPostponedEnterTransition()
return true
}
})
// Scroll to the position of the item that was selected in the Destination Fragment.
itemRecyclerView.addOnLayoutChangeListener { p0, p1, p2, p3, p4, p5, p6, p7, p8 ->
val layoutMan = itemRecyclerView.layoutManager
val viewAtPos = layoutMan?.findViewByPosition(sharedViewModel.currentPos)
if (viewAtPos == null ||
layoutMan.isViewPartiallyVisible(viewAtPos, false, true)
) {
itemRecyclerView.post {
layoutMan?.scrollToPosition(sharedViewModel.currentPos)
}
}
}
}
DestinationFragment
class DestinationFragment : Fragment(), MainActivityListener {
lateinit var sharedViewModel: SharedViewModel
lateinit var destPager : ViewPager
lateinit var itemAdapter : ItemPagerAdapter
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
postponeEnterTransition()
setEnterSharedElementCallback(object : androidx.core.app.SharedElementCallback(){
override fun onMapSharedElements(names: MutableList<String>?, sharedElements: MutableMap<String, View>?) {
val item = sharedViewModel.itemList[destPager.currentItem]
val itemView = (itemAdapter.instantiateItem(destPager, destPager.currentItem) as Fragment).view?.findViewById<TextView>(R.id.item_fragment_textview) as View
names?.clear()
names?.add(item)
sharedElements?.clear()
sharedElements?.put(item, itemView)
}
})
sharedElementEnterTransition = TransitionInflater.from(requireContext()).inflateTransition(android.R.transition.move)
sharedViewModel = ViewModelProviders.of(requireActivity()).get( SharedViewModel::class.java)
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
return inflater.inflate(R.layout.destination_layout, container ,false)
}
override fun onBackPressed(): Boolean {
sharedViewModel.currentPos = destPager.currentItem
return false
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
destPager = destination_pager
itemAdapter = ItemPagerAdapter(sharedViewModel.itemList, childFragmentManager)
destination_pager.adapter = itemAdapter
destination_pager.currentItem = sharedViewModel.currentPos
}

Kotlin RecycleView does not work correctly

I want to create a small application that once the user clicks on floating button action to add element. It will be added automatically
to the top of the recycle view.
I have created for this A main activity which contains the fragment of the recycler and the add flotten.
Once the user clicks on this button a fragmented dialog is shown to insert the element. Once the user confirms i want to add the new element to the top of the recycle view.
TO did I used a global array which contains the item.
I have not implemented the logic yet for that. But what surprised me once I click on confirm button of the shown dialog the element added correctly to the global array, however, the recycle view on his own without any action on it duplicate the latest element.
I used the model view presenter for that and here are my diff classes
1.MainActivity
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
addFragment(InterFragment(), R.id.container)
fab.setOnClickListener { view ->
val dialog = IntervAddFragment()
val ft = supportFragmentManager.beginTransaction()
dialog.show(ft, ContentValues.TAG)
}
}
}
2.ADDFragmet
class IntervAddFragment : DialogFragment(), AddContract.View
{
val presenter: AddPresenter by lazy { AddPresenter(this) }
var dat=""
var plom=""
var typ=""
override fun onCreate(savedInstanceState: Bundle?) { ....}
override fun onStart() {.... }
override fun onCreateView(inflater: LayoutInflater?, parent: ViewGroup?, state: Bundle?): View? {...}
override fun onViewCreated(view: View?, savedInstanceState: Bundle?) {....}
fun on_confirmClick()
{
presenter.on_confirmClick(dat,plom,typ)
Log.e("errrr",presenter.getList().toString())
dismiss()
}
fun fillSpinerPlom(view : View?) {.... }
fun fillSpinerType(view : View?) {.... }
private fun updateDateInView(datep:String) {....}
}
3.IntervFragement
InterFragment: Fragment(), InterContract.View {
var views: View? = null
var List_inter_adapter: InterListAdapter? = null
private var recyclerView: RecyclerView? = null
val presenter: InterventionPresenter by lazy { InterventionPresenter(this) }
override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?,
savedInstanceState: Bundle?): View? {.... }
interface ClickListener {
fun onClick(view: View, position: Int)
fun onLongClick(view: View?, position: Int)
}
internal class RecyclerTouchListener(context: Context, recyclerView: RecyclerView, private val clickListener: ClickListener?) : RecyclerView.OnItemTouchListener {..... }
override fun onInterceptTouchEvent(rv: RecyclerView, e: MotionEvent): Boolean {.....}
override fun onViewCreated(view: View?, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
recyclerView = views!!.findViewById<View>(R.id.interv_item_listview) as RecyclerView
List_inter_adapter = InterListAdapter(activity, presenter.getList(true))
recyclerView!!.adapter = List_inter_adapter
recyclerView!!.layoutManager = LinearLayoutManager(activity)
}
}
4.InterPresenter
class InterventionPresenter(val view: InterContract.View)
{
fun getList(firstTime:Boolean): LinkedList<InterItem> {
if(firstTime)
return populateList().list
else
return items
}
fun populateList(): ListInter
{
val item1 = InterItem(1, DateT(2018, Calendar.FEBRUARY, 6).date, plomb.get(0), types.get(0))
val item2 = InterItem(2, DateT(2018, Calendar.MARCH, 8).date, plomb.get(1), types.get(1))
val item3= InterItem(3, DateT(2018, Calendar.MAY, 10).date, plomb.get(2), types.get(2))
val lstint = ListInter()
lstint.list= LinkedList(listOf(item1, item2, item3))
items=lstint.list
return lstint
}
companion object {
val plomb= LinkedList<String>(listOf("Dina", "Lili", "Wiseem"))
val types= LinkedList<String>(listOf("type1","type2","type3"))
lateinit var items: LinkedList<InterItem>
}
}
5.ADD Presenter
class AddPresenter(val view: AddContract.View)
{
fun on_confirmClick(date:String,plom:String,type:String)
{
val item= InterItem(items.size+1,date,plom,type)
items.push(item)
}
fun getList(): LinkedList<InterItem> {
return items
}
fun getplom(): LinkedList<String>
{ return plomb
}
fun getType(): LinkedList<String>
{ return types
}
}
6.InterListAdapter
class InterListAdapter(private val context: Context, linkedList: LinkedList<InterItem>) : RecyclerView.Adapter<InterListAdapter.ViewHolder>()
{
internal var linkedList = LinkedList<InterItem>()
private val inflater: LayoutInflater
//private lateinit var listener: OnTaskSelected
init {... }
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {... }
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.numero?.text=(linkedList[position].numero).toString()
holder.date?.text=linkedList[position].date
holder.plom?.text=linkedList[position].plom
holder.type?.text=linkedList[position].type
}
override fun getItemCount(): Int {
return linkedList.size
}
inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
var numero: TextView?=null
var date: TextView?=null
var plom: TextView?=null
var type: TextView?=null
var btn_delete: Button?=null
var btn_update: Button?=null
init {
numero = itemView.findViewById(R.id.numero)
date = itemView.findViewById(R.id.date)
plom = itemView.findViewById(R.id.plom)
type = itemView.findViewById(R.id.type)
btn_delete = itemView.findViewById(R.id.btn_supprimer)
btn_update = itemView.findViewById(R.id.btn_modifier)
}
}
}
and here is the ListInter
class ListInter
{
var list= LinkedList<InterItem>()
get() = field
set(value){field = value}
}

RecyclerView can't handle array change event by itself. So, you should notify it by calling the following after you've added element to array:
recyclerView.getAdapter().notifyItemInserted(items.size() - 1)