set this
android:orientation="horizontal"
app:reverseLayout="true"
in the layout doesn't work.
When setting your layout manager set it like so in your Activity.kt file:
mRecyclerView.layoutManager = LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, true);
class HorizontalRecyclerViewActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_horizontal_recycler_view)
val recyclerView = findViewById<RecyclerView>(R.id.recycler_view)
recyclerView.layoutManager = LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false)
recyclerView.adapter = YourAdapter()
}
}
The layoutManager property of the RecyclerView to a LinearLayoutManager with its orientation set to HORIZONTAL. The third argument of the LinearLayoutManager constructor sets the reverse layout, in this case false, meaning that the items will be laid out from left to right.
Then, you set the adapter property of the RecyclerView to an instance of YourAdapter, which is a custom adapter that provides data to the RecyclerView.
Related
I am trying to work wih courutines and recycler view. I've done everything necessary to send requests to the API, but I still can't get the list that should be inside the recycler view. I am using fragment to create list and bottom nav. When I go to the fragment where my list should be, then I get the error: RecyclerView: No layout manager attached; skipping layoutand nothing more. I googled about this error and it says I should define the layout manager in xml, but it alreadt has layuout manager in my fragment
<androidx.recyclerview.widget.RecyclerView 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:id="#+id/list_item"
app:layoutManager="LinearLayoutManager"
Also my adapter and fragment for recycler view look like this:
class MyItemRecyclerViewAdapter(
) : RecyclerView.Adapter<MyItemRecyclerViewAdapter.ViewHolder>() {
var userNameResponse = mutableListOf<UsersNameItem>()
fun setNamesList(names: List<UsersNameItem>) {
this.userNameResponse = userNameResponse.toMutableList()
notifyDataSetChanged()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
return ViewHolder(
FragmentItemBinding.inflate(
LayoutInflater.from(parent.context),
parent,
false
)
)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
val item = userNameResponse[position]
holder.idView.text = item.id
holder.contentView.text = item.name
}
override fun getItemCount(): Int = userNameResponse.size
class ViewHolder(binding: FragmentItemBinding) : RecyclerView.ViewHolder(binding.root) {
val idView: TextView = binding.itemNumber
val contentView: TextView = binding.content
}
}
Fragment:
class ItemFragment : Fragment() {
private var layoutManager: RecyclerView.LayoutManager? = null
private var adapter: RecyclerView.Adapter<MyItemRecyclerViewAdapter.ViewHolder>? = null
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
return inflater.inflate(R.layout.fragment_item_list, container, false)
}
override fun onViewCreated(itemView: View, savedInstanceState: Bundle?) {
super.onViewCreated(itemView, savedInstanceState)
layoutInflater.apply {
layoutManager = LinearLayoutManager(activity)
adapter = MyItemRecyclerViewAdapter()
}
}
companion object {
fun newInstance() = ItemFragment()
}
}
And MainActivity where I set up courutines and trying to make a request:
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
lateinit var nameviewModel: ListNamesViewModel
val adapter = MyItemRecyclerViewAdapter()
///trying to create http-request for lists
val retrofitService = BasicApiService.getInstance()
val mainRepository = MainRepository(retrofitService)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)
nameviewModel = ViewModelProvider(
this,
MyViewModelFactory(mainRepository)
)[ListNamesViewModel::class.java]
nameviewModel.userName.observe(
this, Observer {
adapter.setNamesList(it)
})
nameviewModel.message.observe(this) {
Toast.makeText(this, it, Toast.LENGTH_SHORT).show()
}
nameviewModel.loadUsers()
val navView: BottomNavigationView = binding.navView
val navController = findNavController(R.id.nav_host_fragment_activity_main)
val appBarConfiguration = AppBarConfiguration(
setOf(
R.id.navigation_home,
R.id.navigation_dashboard,
R.id.navigation_notifications,
R.id.list_name_navig
)
)
setupActionBarWithNavController(navController, appBarConfiguration)
navView.setupWithNavController(navController)
}
}
Also I wanted to ask (I am very new to Kotlin nad just trying to make things work) if it is a good practice to leave request to API in the MainActivity ot I should do it in another way?
I see some confusion in your code, try to apply the next:
Why are you creating the layoutManager and adapter in the ItemFragment?
override fun onViewCreated(itemView: View, savedInstanceState: Bundle?) {
super.onViewCreated(itemView, savedInstanceState)
layoutInflater.apply {
layoutManager = LinearLayoutManager(activity)
adapter = MyItemRecyclerViewAdapter()
}
}
You need to move it and RecyclerView to your activity.
The using layoutInflater.apply {} doesn't make sense, it's doing nothing in your case. You need to set layoutManager and adapter to recyclerView then in the activity it should look like that (and rename list_item to recyclerView)
binding.recyclerView.apply {
layoutManager = LinearLayoutManager(this)
adapter = MyItemRecyclerViewAdapter()
}
Remove app:layoutManager="LinearLayoutManager" from XML.
It looks like you don't need to use ItemFragment for your purpose because you use it just like a view and binding in the ViewHolder
class ViewHolder(binding: FragmentItemBinding) : RecyclerView.ViewHolder(binding.root) {
val idView: TextView = binding.itemNumber
val contentView: TextView = binding.content
}
try changing in xml
app:layoutManager="LinearLayoutManager"
to
app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
I have an activity that is controlled with a navigation component, it has few fragments, inside one of these fragments there is a recyclerView that has some items, when I click on an Item I want it to navigate me to another fragment that has additional information about the item, I don't know how to use navigation component inside a recycelerView, when I type findNavController it has some parameters that am not sure what to put in or if its even the right function, I also tried to do it by code like this:
val fm = (context as AppCompatActivity).supportFragmentManager
fm.beginTransaction()
.replace(R.id.fragmentContainer, fragment)
.addToBackStack(null)
.commit()
by the way this is the code that asks for other parameters:
// it asks for a (fragment) or (activity, Int)
findNavController().navigate(R.id.action_settingsFragment_to_groupUnits)
the problem is when I navigate out of this fragment or use the drawer navigation (nav component for the other fragments), this fragment that I navigated to stays displayed in the screen, I see both fragments at the same time, I assume its a fragment backStack issue but I don't know how to solve it, thanks for the help and your time in advance
You do not need to navigate from RecyclerView item click to AdditionalDetails fragment directly.
You can do this same thing by help of interface.
Steps:
Create an interface with a method declaration.
Extend Interface from the fragment where you are using your RecyclerView and Implement interface method.
Pass this interface with the adapter.
Using the interface from adapter you just pass object when click on item.
Finally from your fragment you just navigate to AdditionalDetails fragment with argument.
Lets see sample code from my current project:
Interface
interface ChatListClickListener {
fun onChatListItemClick(view:View, user: User)
}
Adapter Class
class UserAdapter(val Users: List<User>, val chatListClickListener: ChatListClickListener) : RecyclerView.Adapter<UserAdapter.UserViewHolder>() {
inner class UserViewHolder(
val recyclerviewUsersBinding: RecyclerviewChatlistBinding
) : RecyclerView.ViewHolder(recyclerviewUsersBinding.root)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): UserViewHolder {
val vh = UserViewHolder(
DataBindingUtil.inflate(
LayoutInflater.from(parent.context),
R.layout.recyclerview_chatlist,
parent,
false
)
)
return vh
}
override fun onBindViewHolder(holder: UserViewHolder, position: Int) {
holder.recyclerviewUsersBinding.user = Users[position]
holder.recyclerviewUsersBinding.root.setOnClickListener{
chatListClickListener.onChatListItemClick(it,Users[position])
}
}
override fun getItemCount(): Int {
return Users.size
}
}
My fragment
class FragmentChatList : Fragment(), ChatListClickListener {
lateinit var binding: FragmentChatListBinding
lateinit var viewModel: ChatListViewModel
lateinit var listener: ChatListClickListener
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
}
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val args: FragmentChatListArgs by navArgs()
binding = FragmentChatListBinding.inflate(layoutInflater, container, false)
val factory = ChatListFactory(args.user)
viewModel = ViewModelProvider(this, factory).get(ChatListViewModel::class.java)
binding.viewModel = viewModel
listener = this
lifecycleScope.launch {
viewModel.addUserWhenUserConnect()
}
viewModel.userList.observe(viewLifecycleOwner, Observer { data ->
binding.rvChatList.apply {
layoutManager = LinearLayoutManager(requireContext())
setHasFixedSize(true)
adapter = UserAdapter(data, listener)
}
})
return binding.root
}
override fun onChatListItemClick(view: View, user: User) {
Toast.makeText(requireContext(), user.name + "", Toast.LENGTH_SHORT).show()
// here you navigate to your fragment....
}
}
I guess this will be helpful.
I'm using recyclerView to display my data but anything is displaying. The onBindViewHolder is never called and the onCreateViewHolder also.
I initialize the adapter in the viewModel with the data which I got from room but anything is displaying. The data in the viewModel is there when I want give it to the adaptater.
There's the adaptater,
class CountryInfoAdapter : RecyclerView.Adapter<TextItemViewHolder>() {
var data = listOf<DevByteCountryProperty>()
set(value) {
field = value
notifyDataSetChanged()
}
override fun getItemCount() = data.size
override fun onBindViewHolder(holder: TextItemViewHolder, position: Int) {
val item = data[position]
holder.textView.text = item.name.toString()
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): TextItemViewHolder {
//The inflater knows how to create views from XML layout. The context is the context of the RecyclerView.
val layoutInflater = LayoutInflater.from(parent.context)
val view = layoutInflater.inflate(R.layout.text_item_view, parent, false) as TextView
Timber.i("Data from adaptater : ${data.toString()}")
return TextItemViewHolder(view)
}
}
There is the Fragment,
class CountryInfoFragment : Fragment() {
private lateinit var viewModel: CountryInfoViewModel
private lateinit var viewModelFactory: CountryInfoViewModelFactory
private lateinit var binding: FragmentCountryInfoBinding
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?): View? {
binding = DataBindingUtil.inflate(inflater,
R.layout.fragment_country_info,container,false)
val application = requireNotNull(this.activity).application
viewModelFactory = CountryInfoViewModelFactory(application)
viewModel = ViewModelProvider(this,viewModelFactory).get(CountryInfoViewModel::class.java)
binding.viewModel = viewModel
val adapter = CountryInfoAdapter()
viewModel.countriesProperty.observe(viewLifecycleOwner, Observer {
it?.let {
adapter.data = it
}
})
binding.countryList.adapter = adapter
binding.lifecycleOwner = viewLifecycleOwner
setHasOptionsMenu(true)
return binding.root
}
}
Please try below code, setting up layout manager before assigning adapter to recyclerView
binding.countryList.layoutManager = LinearLayoutManager(this)
binding.countryList.adapter = adapter
I'm trying to migrate from Kotlin synthetics to View Binding. How should I View bind from two different layouts. I'm trying to connect a button from fragment Main layout and from custom dialog layout. Right now I can connect button id from fragment main layout.Example code below:
class MainFragment: Fragment(R.layout.fragment_main) {
private var fragmentMainBinding: FragmentMainBinding? = null
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
// Main fragment viewbinding
val binding = FragmentMainBinding.bind(view)
fragmentMainBinding = binding
// FAB button onClick Listener
binding.fabAddItem.setOnClickListener {
// Inflate add_item_dialog.xml custom view
val dialogView = LayoutInflater.from(activity).inflate(R.layout.add_item_dialog, null)
// Add AlertDialog Builder
val dialogBuilder = AlertDialog.Builder(activity)
.setView(dialogView)
//Show custom dialog
val customAlertDialog = dialogBuilder.show()
binding.btnClose.setOnClickListener {
customAlertDialog.dismiss()
}
}
}
}
If you want to get a hold of dialog binding you can do the following
val dialogBinding = AddItemDialogBinding.bind(dialogView)
I have a tabbed activity with fragments. Now I just need to add an actionbar menu. I am guessing I add the action bar in the mainactivity. How can I do this?
I have tried adding an action bar for each fragment but looks like that cannot be done in kotlin. I am new to android development but I was able to perform this task with java. I am converting my small projects to Kotlin which is supposed to be easier than java.
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val sectionsPagerAdapter = SectionsPagerAdapter(this, supportFragmentManager)
val viewPager: ViewPager = findViewById(R.id.view_pager)
viewPager.adapter = sectionsPagerAdapter
val tabs: TabLayout = findViewById(R.id.tabs)
tabs.setupWithViewPager(viewPager)
val fab: FloatingActionButton = findViewById(R.id.fab)
fab.setOnClickListener { view ->
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show()
}
fun onCreateOptionsMenu(menu: Menu): Boolean {
menuInflater.inflate(R.menu.mainmenu, menu)
return true
}
}
}
Actually figured it out. My question was basically senseless. It should have been how to add a menu in an AppBarLayout. My app is using a tabbed activity.
All I had to do was under my main activity layout, I needed to add a toolbar under the Appbarlayout.
then under the Main activity Oncreate, I added
setSupportActionBar(toolbar)
val actionBar = supportActionBar
Then call the oncreateoptionsmenu
override fun onCreateOptionsMenu(menu: Menu): Boolean {
// Inflate the menu to use in the action bar
val inflater = menuInflater
inflater.inflate(R.menu.mainmenu, menu)
return super.onCreateOptionsMenu(menu)
}