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)
Related
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 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)
}
I'm working on a Kotlin coded app using the Navigation Drawer Layout with a list of items. When I open the drawer using the icon at the top left I want it to notifyDataSetChanged so that the list is updated from outside the MainActivity. This includes pressing the back button, swiping open the drawer, or clicking the stacked lines icon at the top left
Here's a simplified version of my code, but it's essentially a Navagation Drawer Activity with a recyclerView for the context of my question:
class MainActivity : AppCompatActivity() {
lateinit var drawerLayout: DrawerLayout
lateinit var navView: NavigationView
lateinit var toolbar: Toolbar
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
toolbar = findViewById(R.id.app_bar_toolbar)
setSupportActionBar(toolbar)
drawerLayout = findViewById(R.id.drawer_layout)
navView = nav_view
val toggle = ActionBarDrawerToggle(this, drawerLayout, toolbar,
R.string.navigation_drawer_open, R.string.navigation_drawer_close)
drawerLayout.addDrawerListener(toggle)
toggle.syncState()
}
I've spent several hours trying anything I can, but primarily I can't get this to work:
override fun onDrawerOpen(view:View){
... myAdapter.notifyDataSetChanged()
super.onDrawerOpen(view)
}
it gives me the hint "overrides nothing" or "unused", and if I try to add it to any of my code in onCreate it states "Modifier 'override' not applicable to local function.
What am I doing wrong? Is there a better way to notify a data change when the drawer is opened?
The Question is old, but to whom has the same problem:
Just Create new class that implements DrawerListener and write your logic inside appropriate method:
private inner class MyDrawerListener(): DrawerListener {
override fun onDrawerSlide(drawerView: View, slideOffset: Float) {
}
override fun onDrawerOpened(drawerView: View) {
}
override fun onDrawerClosed(drawerView: View) {
}
override fun onDrawerStateChanged(newState: Int) {
}
}
Now add listener as:
drawerLayout.addDrawerListener(MyDrawerListener())
I have an activity with a tabbed layout containing multiple different tabs. Each tab contains a number of 'edittext' fields. I have a button on the main activity and on clicking it i want to save the the contents of each edittext field from each tab. Currently i can return an ordinary value from the tab but i can not get the contents of the edittext field.
I have tried creating a 'lateinit var frag1_tenNo : EditText' within the fragment class for a tab. I have initialized it in the onCreateView but the program crashes saying 'lateinit property frag1_tenNo has not been initialized'
fragment code
class frag1: Fragment() {
lateinit var frag1_tenNo : EditText
override public fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val viewFrag1 = inflater.inflate(R.layout.frag1, container, false)
frag1_tenNo = viewFrag1.findViewById(R.id.survey_tenantNo)
return viewFrag1
}
fun saveFrag1Data(): String {
var data1 = frag1_tenNo.text.toString()
return data1
}
activity code - to retrieve data
save_btn.setOnClickListener {
Log.d("Survey","Change Button Clicked")
val test = frag1().saveFrag1Data()
Log.d("Survey","Returned value : $test")
}
val test = frag1().saveFrag1Data()
Here you create a new fragment. OnCreate method of this fragment isn't called yet. So quite predictably you get lateinit property frag1_tenNo has not been initialized error.
It is an activity hosting a pager fragment which has android.support.v4.view.ViewPager and the adapter class derived from FragmentStatePagerAdapter.
The problem is from the pager fragment it has two or three fragments cached, but the data is not parseable (including a view dynamically getting from a 3rd part sdk), when sometime os recreate this fragment in case like minimize/reopen it, or after rotation the restored fragment are blank (using the one from cache and lacking data).
Not find a way to re-populate the fragments restored by os through the pager fragment's recreation flow.
Even tried in the pager fragment to clear the adapter's data in onActivityCreated()
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
val childFragmentManager = childFragmentManager
mAdapter = ContentPagerAdapter( activity as Context,
childFragmentManager, emptyList())
mContentViewPager!!.setAdapter(mAdapter)
mAdapter?.setData(emptyList())
}
the adapter:
fun setData(itemsList: List<Data>) {
this.data = itemsList
notifyDataSetChanged()
}
the viewPager seems still showing the previous cachhed fragment without expected data after the re-creation flow is complete. (tried to make sure it is from the cached one, by in the fragment's onsaveInstance() to save the position of the data in the adapter data list, and the re-created fragment in the viewPager got that position, so it is a os re-created one from cache. But how could it be after at beging already set the adapter with empty list at onActivityCreated()).
Cannt resolve with clean the fragments by setting data to empty.
So tried to remove the page fragment from the activity at onDestroy() with hope that there will be no fragment to be put in cache:
class ContentPagerFragment :Fragment {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val view = inflater.inflate(R.layout.content_pager, container, false)
mContentViewPager = view.findViewById(R.id.contentViewPager)
return view
}
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
val childFragmentManager = childFragmentManager
mAdapter = ContentPagerAdapter( activity as Context,
childFragmentManager, emptyList())
mContentViewPager!!.setAdapter(mAdapter)
mAdapter?.setData(emptyList())
}
interface RemoveFragmentAtClose {
fun onContentPagerFragmentDoestroy()
}
override fun onDestroy() {
(activity as? RemoveAtCloseFragment)?
.onContentPagerFragmentDoestroy()
super.onDestroy()
}
}
and in the hosting activity
class HostActivity : AppCompatActivity(),
ContentPagerFragment.RemoveFragmentAtClose {
override fun onContentPagerFragmentDoestroy() {
supportFragmentManager.beginTransaction().
remove(supportFragmentManager.findFragmentById(R.id.pagerFragmentContainer))
.commitAllowingStateLoss()
var contentPagerFragment = ContentPagerFragment::class.java.cast(supportFragmentManager
.findFragmentById(R.id.pagerFragmentContainer))
Log.i(TAG, " onContentPagerFragmentDoestroy(), this $this" +
"\ngetContentPagerFragment: $contentPagerFragment"
)
}
override fun onAttachFragment(fragment: Fragment) {
Log.d(TAG, " onAttachFragment(), " +
"fragment: $fragment \nthis $this")
}
}
But the log shows that the supportFragmentManager.findFragmentById(R.id.pagerFragmentContainer) still find the fragment after the .commitAllowingStateLoss() call.
And when os restores the activity the ContentPagerFragment is showing up in the activity's onAttachFragment(fragment: Fragment) before activity's onCreate(savedInstanceState: Bundle?) is called.
Why is the viewPager using the old fragment after remove the pager fragment from the activity's supportFragmentManager?
How to prevent the view pager from use the cached fragment?