Develop Reference

Android Kotlin fragment's onCreate not called

I am trying to display Fragment but I do not know why I can't do that. Here is my code:
The main_activity.xml:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".view.MainActivity">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/fragment_container" />
</androidx.constraintlayout.widget.ConstraintLayout>
Followed by MainActivity.kt:
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?, persistentState: PersistableBundle?) {
super.onCreate(savedInstanceState, persistentState)
setContentView(R.layout.main_activity)
supportFragmentManager.beginTransaction().apply {
replace(R.id.fragment_container, CurrencyListFragment())
addToBackStack(null)
commit()
}
}
}
The layout currency_list_fragment.xml:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".view.CurrencyListFragment">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/rvItem"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"/>
<ProgressBar
android:id="#+id/progress_bar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="visible"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
Another class CurrencyListFragment.kt:
class CurrencyListFragment : Fragment(), MainContract.View {
private val restModel: RestModel = RestModel()
lateinit var mainPresenter: MainPresenter
var isLoading: Boolean = false
var apiResponseList: MutableList<ApiResponse> = arrayListOf()
lateinit var itemAdapter: ItemAdapter
var handler: Handler = Handler()
lateinit var _layoutManager: LinearLayoutManager
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
Log.e("a","a")
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
Log.e("a","a")
return inflater.inflate(R.layout.currency_list_fragment,container,false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
Log.e("a1","a1")
_layoutManager = LinearLayoutManager(activity)
mainPresenter = activity?.let { MainPresenter(this, it.getPreferences(Context.MODE_PRIVATE)) }!!
val currentDate = mainPresenter.convertDate()
mainPresenter.makeACall("2021-07-22")
addScrollerListener()
}
private fun addScrollerListener() {
rvItem.addOnScrollListener(object : RecyclerView.OnScrollListener() {
override fun onScrollStateChanged(_rvItem: RecyclerView, newState: Int) {
super.onScrollStateChanged(_rvItem, newState)
if (!isLoading) {
if (!_rvItem.canScrollVertically(1)) {
loadMore()
isLoading = true
}
}
}
})
}
private fun loadMore() {
//notify adapter using Handler.post() or RecyclerView.post()
handler.post {
apiResponseList.add(ApiResponse("", "", listOf(Currency2("", 0f)), true))
itemAdapter.notifyItemInserted(apiResponseList.size - 1)
}
handler.postDelayed({
apiResponseList.removeAt(apiResponseList.size - 1)
val listSize = apiResponseList.size
itemAdapter.notifyItemRemoved(listSize)
val nextLimit = listSize + 1
for (i in listSize until nextLimit) {
apiResponseList.add(
ApiResponse("", "2020-06-11", listOf(Currency2("a", 2f)), false)
)
}
itemAdapter.notifyDataSetChanged()
isLoading = false
}, 2000)
}
override fun onDestroy() {
super.onDestroy()
restModel.cancelJob()
}
}
Neither of onCreate(), onCreateView() nor onViewCreated() are not called (I suppose that because Logs texts are not shown in Logcat. I guess I added everything you need to solve my problem but if I am wrong and you need something more just ask. Why is that so?
Thank you very much for help!

It turned out I overrided wrong onCreate method on my class extending AppCompatActivity.

How to replace fragment inside ViewPager and change toolbar

I found an interesting feature in one of the applications, I want to repeat it. The application has ViewPager and TabLayout and a bunch of fragments inside.
On the first fragment there is a button img1
, by pressing it, the fragment is replaced by another img2
while ads_banner is removed and the toolbar is replaced,
and when swiping to the right and back, it shows fragment1, please tell me how this can be done. Here is what I already wrote:
MainActivity
class MainActivity : AppCompatActivity() {
private var mAdView: AdView? = null
#SuppressLint("ResourceType")
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val adRequest = AdRequest.Builder().build()
mAdView = findViewById(R.id.adView)
mAdView!!.loadAd(adRequest)
initTab()
}
fun initTab() {
tab_layout.addTab(tab_layout.newTab().setIcon(R.drawable.image1)
tab_layout.addTab(tab_layout.newTab().setIcon(R.drawable.image2)
tab_layout.addTab(tab_layout.newTab().setIcon(R.drawable.image3)
tab_layout.tabGravity = TabLayout.GRAVITY_FILL
val adapter = MyPagerAdapter(supportFragmentManager, tab_layout.tabCount)
pager.adapter = adapter
pager.offscreenPageLimit = 2
pager.addOnPageChangeListener(TabLayout.TabLayoutOnPageChangeListener(tab_layout))
tab_layout.addOnTabSelectedListener(object : TabLayout.OnTabSelectedListener {
override fun onTabSelected(tab: TabLayout.Tab) {
pager.currentItem = tab.position
if (tab.position == 0) {
tab_layout.getTabAt(0)!!.setIcon(R.drawable.image1_focus)
}
if (tab.position == 1) {
tab_layout.getTabAt(1)!!.setIcon(R.drawable.image2_focus)
}
if (tab.position == 2) {
tab_layout.getTabAt(2)!!.setIcon(R.drawable.image3_focus)
}
}
override fun onTabUnselected(tab: TabLayout.Tab) {
if (tab.position == 0) tab_layout.getTabAt(0)!!.setIcon(R.drawable.image1)
if (tab.position == 1) tab_layout.getTabAt(1)!!.setIcon(R.drawable.image2)
if (tab.position == 2) tab_layout.getTabAt(2)!!.setIcon(R.drawable.image3)
}
override fun onTabReselected(tab: TabLayout.Tab) {
}
})
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
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/mainlayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/white"
android:fitsSystemWindows="true"
android:orientation="vertical"
tools:context=".MainActivity">
<com.google.android.gms.ads.AdView
android:id="#+id/adView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:background="#color/transparent"
app:adSize="SMART_BANNER"
app:adUnitId="#string/banner_key"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
style="#style/MyToolbar"
android:layout_width="match_parent"
android:layout_height="35dp"
android:layout_marginTop="2dp"
android:gravity="center"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/adView"
app:popupTheme="#style/AppTheme.PopupOverlay">
<TextView
android:id="#+id/toolbar_txt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:fontFamily="#font/sf_pro_display_regular"
android:textColor="#color/black"
android:textSize="24sp"
tools:layout_editor_absoluteX="206dp"
tools:layout_editor_absoluteY="7dp" />
</androidx.appcompat.widget.Toolbar>
<androidx.viewpager.widget.ViewPager
android:id="#+id/pager"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="#+id/tab_layout"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/toolbar" />
<com.google.android.material.tabs.TabLayout
android:id="#+id/tab_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:background="#fff"
android:elevation="6dp"
android:minHeight="?attr/actionBarSize"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:tabBackground="#drawable/tab_color_selector"
app:tabIndicatorColor="#2196F3"
app:tabIndicatorGravity="top"
app:tabIndicatorHeight="4dp" />
</androidx.constraintlayout.widget.ConstraintLayout>
MyPagerAdapter
class MyPagerAdapter(fm: FragmentManager, internal var mNumOfTabs: Int) : FragmentStatePagerAdapter(fm) {
override fun getItem(position: Int): Fragment {
when (position) {
0 -> {
return RootFragment()
// return Fragment1()
}
1 -> {
return Fragment2()
}
2 -> {
return Fragment3()
}
}
}
override fun getCount(): Int {
return mNumOfTabs
}
}
Fragment1
class Fragment1: Fragment() {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val view = inflater.inflate(R.layout.fragment_1, container, false)
return view
}
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
btnfr1.setOnClickListener {
val trans = fragmentManager!!.beginTransaction()
trans.replace(R.id.root_frame, Fragment4())
trans.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN)
trans.addToBackStack(null)
trans.commit()
}
}
RootFragment
class RootFragment : Fragment() {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val view = inflater.inflate(R.layout.root_fragment, container, false)
val transaction = fragmentManager!!.beginTransaction()
transaction.replace(R.id.root_frame, Fragment1())
transaction.commit()
return view
}
}
root_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/root_frame" >
</FrameLayout>
In Fragment1, only the button for calling Fragment4. Tried to do as here https://www.codexpedia.com/android/android-viewpager-fragment-swap/
it turned out to replace Fragment1 with Fragment4, but I don’t know how to reset Fragment4 when swiping and don’t understand how to replace Toolbar and remove ads.

The trick is that as RootFragment is the fragment on the 0th index, what you need to do is show the original fragment as a child fragment of RootFragment using fragment transactions via childFragmentManager.
This way, you can replace the children of RootFragment, without actually having to replace RootFragment itself inside the ViewPager.

You need to implement createFragment and getItemCount methods in MyPagerAdapter to supply instances of fragments as pages to ViewPager.
Modify MyPagerAdapter class as shown below and test:
class MyPagerAdapter(fm: FragmentManager, internal var mNumOfTabs: Int) : FragmentStatePagerAdapter(fm) {
override fun getItemCount(): Int = mNumOfTabs
override fun createFragment(position: Int): Fragment {
when (position) {
0 -> {
return RootFragment()
}
1 -> {
return Fragment2()
}
2 -> {
return Fragment3()
}
}
}
}

RecyclerView doesn't appear when back pressed

I see the problem with a RecyclerView in viewpager fragment and I use bottom naviagation bar. When I tab on the navigation bar to change a screen and then pressed on back button it will go to the first screen which have the viewpager but the recyclerview doesn't appear and when I tab the naviagtion bar to reselect this screen it appear.
The recyclerview is show the list from firestore database and using ViewModel.
I try to set retainInstance to true but it doesn't work. And try to setup the recyclerview in onCreate and onCreateView it doesn't work too.
Edit: this is my code.
MainActivity.kt
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val navView: BottomNavigationView = findViewById(R.id.nav_view)
val navController = findNavController(R.id.nav_host_fragment)
navView.setupWithNavController(navController)
}
override fun onOptionsItemSelected(item: MenuItem): Boolean {
when (item.itemId){
android.R.id.home -> {
onBackPressed()
return true
}
}
return super.onOptionsItemSelected(item)
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<com.google.android.material.bottomnavigation.BottomNavigationView
android:id="#+id/nav_view"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="0dp"
android:layout_marginEnd="0dp"
android:background="#drawable/bg_nav"
app:itemIconTint="#color/navbar_color"
app:itemTextColor="#color/navbar_color"
app:itemTextAppearanceActive="#style/navbar_font"
app:itemTextAppearanceInactive="#style/navbar_font"
app:itemBackground="#drawable/nav_ripple"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:menu="#menu/bottom_nav_menu"/>
<fragment
android:id="#+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="0dp"
android:layout_height="0dp"
app:defaultNavHost="true"
app:layout_constraintBottom_toTopOf="#id/nav_view"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="#navigation/mobile_navigation" />
</androidx.constraintlayout.widget.ConstraintLayout>
HomeFragement.kt (it contain tablayout and viewpager)
class HomeFragment : Fragment() {
private lateinit var homeViewModel: HomeViewModel
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
homeViewModel =
ViewModelProviders.of(this).get(HomeViewModel::class.java)
val root = inflater.inflate(R.layout.fragment_home, container, false)
return root
}
override fun onActivityCreated(savedInstanceState: Bundle?) {
super.onActivityCreated(savedInstanceState)
setupTab()
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
}
private fun setupTab(){
Log.d("SET UP TAB", "SETTING UP")
val pageTabAdapter = PageTabAdapter(activity!!.supportFragmentManager, activity_tab.tabCount)
view_activity.adapter = pageTabAdapter
view_activity.addOnPageChangeListener(TabLayout.TabLayoutOnPageChangeListener(activity_tab))
activity_tab.setOnTabSelectedListener(object : TabLayout.OnTabSelectedListener{
override fun onTabReselected(p0: TabLayout.Tab?) {
}
override fun onTabUnselected(p0: TabLayout.Tab?) {
}
override fun onTabSelected(p0: TabLayout.Tab?) {
view_activity.currentItem = p0!!.position
}
})
}
}
fragment_home.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/white"
android:orientation="vertical">
<TextView
android:id="#+id/home_header"
style="#style/page_header"
android:text="#string/title_home"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"/>
<Button
android:id="#+id/calendar_btn"
android:layout_width="60dp"
android:layout_height="40dp"
android:background="#drawable/btn_calendar"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="#id/home_header"
app:layout_constraintBottom_toBottomOf="#id/home_header"
android:layout_marginEnd="10dp"/>
<com.google.android.material.tabs.TabLayout
android:id="#+id/activity_tab"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabRippleColor="#color/colorPrimary"
app:tabTextAppearance="#style/tab_font"
app:tabIndicatorHeight="2.5dp"
app:tabGravity="fill"
app:layout_constraintTop_toBottomOf="#id/home_header"
app:layout_constraintStart_toStartOf="parent"
android:background="#android:color/white">
<com.google.android.material.tabs.TabItem
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="กิจกรรมในเดือนนี้" />
<com.google.android.material.tabs.TabItem
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="กิจกรรมที่ผ่านไปแล้ว" />
</com.google.android.material.tabs.TabLayout>
<androidx.viewpager.widget.ViewPager
android:id="#+id/view_activity"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintTop_toBottomOf="#id/activity_tab"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintBottom_toBottomOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>
PageAdapter.kt
class PageTabAdapter(private val fragmentManager: FragmentManager, private val anInt: Int) :
FragmentStatePagerAdapter(fragmentManager) {
override fun getItem(position: Int): Fragment {
return when (position) {
0 -> {
NewActivity.newInstance()
}
1 -> {
PastActivity.newInstance()
}
else -> {
null!!
}
}
}
override fun getCount(): Int {
return anInt
}
}
ActivityAdapter.kt (this is a recyclerview adapter)
class ActivityAdapter(
private val mContext: Context, private val mItems: List<ActivityModel>
): RecyclerView.Adapter<ActivityAdapter.Holder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): Holder {
val inflater = LayoutInflater.from(this.mContext)
val view = inflater.inflate(R.layout.activity_list, parent, false)
return Holder(view)
}
override fun getItemCount(): Int {
return this.mItems.size
}
override fun onBindViewHolder(holder: Holder, position: Int) {
val item = this.mItems[position]
holder.setName(item.name)
val date = item.date?.toDate()
val dateFormat: DateFormat = SimpleDateFormat("dd-MMM-yyyy")
val newDate = dateFormat.format(date).toString()
holder.setDate(newDate)
val period = item.start + " - " +item.end
holder.setPeriod(period)
holder.setButton(item)
}
inner class Holder(view: View): RecyclerView.ViewHolder(view){
private var activityName: TextView = view.activity_list_name
private var activityDate: TextView = view.activity_list_date
private var activityPeriod: TextView = view.activity_list_period
private var activityPicture: ImageView = view.activity_list_pic
private var activityButton: Button = view.activity_list_btn
fun setName(name: String?){
this.activityName.text = name
}
fun setDate(date: String?){
this.activityDate.text = date
}
fun setPeriod(period: String?){
this.activityPeriod.text = period
}
fun setPicture(picpath: String?){
}
fun setButton(data: ActivityModel){
}
}
}
}
PS.: I'm using Kotlin in my project
Thank you

How to implement RecyclerViewPager in kotlin?

I am trying to implement RecyclerViewPagerIndicator in my project, but I can't get it to work.
I work with Kotlin and AndroidX
I expect send a array with text and images from database and show in RecyclerViewPager, something like tinder.

I would suggest you to use dotsIndicator, since it
supports ViewPager 2 which is based on RecyclerView
is maintained, one you picked is not (project seems abandoned)
is written in Kotlin
Example:
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="center"
tools:context=".MainActivity">
<androidx.viewpager2.widget.ViewPager2
android:id="#+id/view_pager_2"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
<com.tbuonomo.viewpagerdotsindicator.WormDotsIndicator
android:id="#+id/dots_indicator"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="16dp"/>
</LinearLayout>
MainActivity.kt
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
setupViewPager2()
}
private fun setupViewPager2() {
val viewPager2 = findViewById<ViewPager2>(R.id.view_pager_2)
val dotsIndicator = findViewById<WormDotsIndicator>(R.id.dots_indicator)
viewPager2.adapter = PagerAdapter(this)
dotsIndicator.setViewPager2(viewPager2)
}
}
PagerAdapter.kt
class PagerAdapter(fa:FragmentActivity): FragmentStateAdapter(fa) {
override fun getItemCount(): Int = 3
override fun createFragment(position: Int): Fragment {
return when(position){
0 -> SampleFragment.newInstance("One", "desc 1")
1 -> SampleFragment.newInstance("Two", "desc 2")
2 -> SampleFragment.newInstance("Three", "desc 3")
else -> throw Exception("No such position")
}
}
}
fragment_sample.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="center"
tools:context=".SampleFragment">
<TextView
android:id="#+id/txt_header"
tools:text="Header 1"
android:textAlignment="center"
android:textSize="24sp"
android:gravity="center"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<TextView
android:id="#+id/txt_desc"
tools:text="Desc 1"
android:textAlignment="center"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
SampleFragment.kt
class SampleFragment : Fragment() {
private var header: String? = null
private var desc: String? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
arguments?.let {
header = it.getString(ARG_Header)
desc = it.getString(ARG_Desc)
}
}
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val view = inflater.inflate(R.layout.fragment_sample, container, false)
setView(view)
return view
}
private fun setView(view:View){
val headerText = view.findViewById<TextView>(R.id.txt_header)
headerText.text = header
val descText = view.findViewById<TextView>(R.id.txt_desc)
descText.text = desc
}
companion object {
#JvmStatic
fun newInstance(param1: String, param2: String) =
SampleFragment().apply {
arguments = Bundle().apply {
putString(ARG_Header, param1)
putString(ARG_Desc, param2)
}
}
}
}

button.setOnClickListener in fragment is not working

this is my layout -> fragment_three.xml
<ScrollView
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/supportback">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
//some Textviews here...
<Button
android:id="#+id/sendButton"
android:layout_width="58dp"
android:layout_height="51dp"
android:layout_gravity="right"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:clickable="true"
android:background="#drawable/send_email"/>
</LinearLayout>
</ScrollView>
and this is my fragment:
class fragmentC : Fragment() {
companion object {
fun newInstance():Fragment {
var fb :fragmentC = fragmentC()
return fb
}}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val rootView = inflater.inflate(R.layout.fragment_three,container,false)
val btn = rootView.findViewById(R.id.sendButton) as Button
btn.setOnClickListener {
Toast.makeText(context,"test",Toast.LENGTH_LONG).show()
}
return rootView
}}
no error, no exception, nothing wrong in the logcat.
I could not find the problem yet, any help please ?
edit1
this is the layout where the fragment should be work in:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context=".MainActivity"
android:id="#+id/activity_main">
<FrameLayout
android:id="#+id/frame_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/navigation"
android:animateLayoutChanges="true">
</FrameLayout>
<android.support.design.widget.BottomNavigationView
android:id="#+id/navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="#389486"
app:menu="#menu/bottom_view">
</android.support.design.widget.BottomNavigationView>
</RelativeLayout>
P.S : there are tow other fragments but it's blank right now i didn't touch it yet
edit2
the main activity class
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
navigation.setOnNavigationItemSelectedListener (object : BottomNavigationView.OnNavigationItemSelectedListener{
override fun onNavigationItemSelected(item: MenuItem): Boolean {
when(item.itemId){
R.id.bot_list ->{
drawerLayout.openDrawer(Gravity.START)
}
R.id.bot_home ->{
var ft : FragmentTransaction = supportFragmentManager.beginTransaction()
ft.replace(R.id.frame_layout,fragmentA.newInstance())
ft.commit()
}
R.id.bot_cart ->{
var ft : FragmentTransaction = supportFragmentManager.beginTransaction()
ft.replace(R.id.frame_layout,fragmentB.newInstance())
ft.commit() }
R.id.bot_message ->{
//here is the required fragment
var ft : FragmentTransaction = supportFragmentManager.beginTransaction()
ft.replace(R.id.frame_layout,fragmentC.newInstance())
ft.commit() }
}
return true
}
})
var ft : FragmentTransaction = supportFragmentManager.beginTransaction()
ft.replace(R.id.frame_layout,fragmentA.newInstance())
ft.commit()
}
}

i don't know what caused the problem but modifying the code like below solve it
class fragmentC : Fragment(),View.OnClickListener {
companion object {
fun newInstance():Fragment {
var fb :fragmentC = fragmentC()
return fb
}
}
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val rootView = inflater.inflate(R.layout.fragment_three, container, false)
val location: Button = rootView.findViewById(R.id.sendButton)
location.setOnClickListener(this)
return rootView
}
override fun onClick(v: View) {
Toast.makeText(context,"test",Toast.LENGTH_LONG).show()
}
}