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Not navigate to fragment with #Inject constructor

I'm trying to create a simple news app, but when I used of #Inject constructor in my fragment, the navigation component not worked and show the below error... while, before used injection, it's worked without any problem
what I doing to fix this error?! thank you so much for your help
NewsActivity:
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.navigation.fragment.findNavController
import androidx.navigation.ui.setupWithNavController
import com.example.simplenewsapp.R
import dagger.hilt.android.AndroidEntryPoint
import kotlinx.android.synthetic.main.activity_news.*
#AndroidEntryPoint
class NewsActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_news)
bottomNavigationView.setupWithNavController(newsNavHostFragment.findNavController())
}
}
BreakingNewsFragment:
class BreakingNewsFragment #Inject constructor(
val newsItemAdapter: NewsAdapter,
var viewModel: MainViewModel? = null
) : Fragment(R.layout.fragment_breaking_news) {
...
}
Error message:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.simplenewsapp, PID: 8558
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.simplenewsapp/com.example.simplenewsapp.ui.NewsActivity}: android.view.InflateException: Binary XML file line #17: Binary XML file line #17: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2913)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: android.view.InflateException: Binary XML file line #17: Binary XML file line #17: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #17: Error inflating class fragment
Caused by: androidx.fragment.app.Fragment$InstantiationException: Unable to instantiate fragment com.example.simplenewsapp.ui.fragments.BreakingNewsFragment: could not find Fragment constructor
at androidx.fragment.app.Fragment.instantiate(Fragment.java:625)
at androidx.fragment.app.FragmentContainer.instantiate(FragmentContainer.java:57)
at androidx.fragment.app.FragmentManager$3.instantiate(FragmentManager.java:483)
at androidx.navigation.fragment.FragmentNavigator.instantiateFragment(FragmentNavigator.java:132)
at androidx.navigation.fragment.FragmentNavigator.navigate(FragmentNavigator.java:162)
at androidx.navigation.fragment.FragmentNavigator.navigate(FragmentNavigator.java:58)
at androidx.navigation.NavGraphNavigator.navigate(NavGraphNavigator.java:71)
at androidx.navigation.NavGraphNavigator.navigate(NavGraphNavigator.java:28)
at androidx.navigation.NavController.navigate(NavController.java:1059)
at androidx.navigation.NavController.onGraphCreated(NavController.java:639)
at androidx.navigation.NavController.setGraph(NavController.java:592)
at androidx.navigation.NavController.setGraph(NavController.java:557)
at androidx.navigation.NavController.setGraph(NavController.java:539)
at androidx.navigation.fragment.NavHostFragment.onCreate(NavHostFragment.java:248)
at androidx.fragment.app.Fragment.performCreate(Fragment.java:2936)
at androidx.fragment.app.FragmentStateManager.create(FragmentStateManager.java:472)
at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:278)
at androidx.fragment.app.FragmentLayoutInflaterFactory.onCreateView(FragmentLayoutInflaterFactory.java:141)
at androidx.fragment.app.FragmentController.onCreateView(FragmentController.java:135)
at androidx.fragment.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:313)
at androidx.fragment.app.FragmentActivity.onCreateView(FragmentActivity.java:292)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:780)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:866)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374) E/AndroidRuntime: at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:696)
at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:170)
at com.example.simplenewsapp.ui.NewsActivity.onCreate(NewsActivity.kt:26)
at android.app.Activity.performCreate(Activity.java:7136)
at android.app.Activity.performCreate(Activity.java:7127)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2893)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: java.lang.NoSuchMethodException: <init> []
at java.lang.Class.getConstructor0(Class.java:2327)
at java.lang.Class.getConstructor(Class.java:1725)
at androidx.fragment.app.Fragment.instantiate(Fragment.java:610)
... 47 more
at
com.example.simplenewsapp.ui.NewsActivity.onCreate(NewsActivity.kt:26)
is:
setContentView(R.layout.activity_news)

All the provided answers are wrong as fragments constructor do NOT have to be empty! You can easily constructor inject your dependencies inside your fragments, but you have to use a fragment factory in order to do so.
Here is an example for you:
Fragment
#AndroidEntryPoint
class BreakingNewsFragment(
val newsItemAdapter: NewsAdapter,
) : Fragment(R.layout.fragment_breaking_news) {
...
}
Fragment Factory
class MainFragmentFactory #Inject constructor(
private val newsAdapter: NewsAdapter
// your dependencies
) : FragmentFactory() {
override fun instantiate(classLoader: ClassLoader, className: String): Fragment = when(className) {
BreakingNewsFragment::class.java.name -> BreakingNewsFragment(newsAdapter)
// here you can add every other fragment
else -> super.instantiate(classLoader, className)
}
}
MainNavHostFragment
#AndroidEntryPoint
class MainNavHostFragment : NavHostFragment() {
#Inject lateinit var mainFragmentFactory: MainFragmentFactory
override fun onAttach(context: Context) {
super.onAttach(context)
childFragmentManager.fragmentFactory = mainFragmentFactory
}
}
Then in order to use your new NavHostFragment, you have to change your activity_main.xml
Activity_main.xml
<fragment
android:id="#+id/fragment_container"
android:name="yourPath.MainNavHostFragment"
android:layout_width="match_parent"
android:layout_height="0dp"
app:defaultNavHost="true"
app:navGraph="#navigation/nav_main" />
The important line being here "android:name="yourPath.MainNavHostFragment" or for example "android:name="com.example.app.ui.MainNavHostFragment"
With this you can constructor inject inside your fragment.
NOTE:
You can NOT constructor inject your viewmodel! You should also be careful with using this method and constructor injecting adapters as they can possibility cause a memory leak. With adapters, I would advise you to field inject them

Fragments should have an empty constructor since they are managed by Android, same as activities. Anything you want to inject you have to inject inside the fragment, not through the constructor.
For view-models, it's trivial through the viewModels() API:
private val viewModel: MainViewModel by viewModels()
Don't forget to annotate the fragment with #AndroidEntryPoint and the view-model with #HiltViewModel.

Add #AndroidEntryPoint to your fragment and initialize NewsAdapter() in onViewCreated method of fragments.
Get MainViewModel by using
private val MainViewModel by viewModels()
Fragments MUST have an empty constructor since they are created by System OS.

Android TV player inflating error on PlaybackTransportRowPresenter.createRowViewHolder

I wrote bellow code in fragment that extends 'VideoSupportFragment'
val playerGlue = PlaybackTransportControlGlue(
activity,
MediaPlayerAdapter(activity))
playerGlue.setHost(VideoSupportFragmentGlueHost(this))
playerGlue.addPlayerCallback(object : PlaybackGlue.PlayerCallback() {
override fun onPreparedStateChanged(glue: PlaybackGlue) {
if (glue.isPrepared()) {
//playerGlue.seekProvider = MySeekProvider()
playerGlue.play()
}
}
})
playerGlue.playerAdapter?.setDataSource(Uri.parse("http://techslides.com/demos/sample-videos/small.mp4"))
When setHost is called app crashes and bellow log appears in logcat.
If i comment setHost, just audio get play.
2020-03-15 02:32:15.578 1779-1779/tv.debug E/AndroidRuntime: FATAL EXCEPTION: main
Process: tv.debug, PID: 1779
android.view.InflateException: Binary XML file line #33: Binary XML file line #33: Error inflating class <unknown>
Caused by: android.view.InflateException: Binary XML file line #33: Error inflating class <unknown>
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:430)
at android.view.LayoutInflater.createView(LayoutInflater.java:645)
at com.android.internal.policy.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:58)
at android.view.LayoutInflater.onCreateView(LayoutInflater.java:717)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:785)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:727)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:858)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:821)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:861)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:821)
at android.view.LayoutInflater.inflate(LayoutInflater.java:518)
at android.view.LayoutInflater.inflate(LayoutInflater.java:426)
at androidx.leanback.widget.PlaybackTransportRowPresenter.createRowViewHolder(PlaybackTransportRowPresenter.java:684)
at androidx.leanback.widget.RowPresenter.onCreateViewHolder(RowPresenter.java:326)
at androidx.leanback.widget.ItemBridgeAdapter.onCreateViewHolder(ItemBridgeAdapter.java:352)
at androidx.recyclerview.widget.RecyclerView$Adapter.createViewHolder(RecyclerView.java:7078)
at androidx.recyclerview.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:6235)
at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6118)
at androidx.recyclerview.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:6114)
at androidx.leanback.widget.GridLayoutManager.getViewForPosition(GridLayoutManager.java:1085)
at androidx.leanback.widget.GridLayoutManager$2.createItem(GridLayoutManager.java:1613)
at androidx.leanback.widget.SingleRow.appendVisibleItems(SingleRow.java:113)
at androidx.leanback.widget.Grid.appendOneColumnVisibleItems(Grid.java:389)
at androidx.leanback.widget.GridLayoutManager.appendOneColumnVisibleItems(GridLayoutManager.java:1839)
at androidx.leanback.widget.GridLayoutManager.onLayoutChildren(GridLayoutManager.java:2276)
at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:4134)
at androidx.recyclerview.widget.RecyclerView.dispatchLayout(RecyclerView.java:3851)
at androidx.recyclerview.widget.RecyclerView.consumePendingUpdateOperations(RecyclerView.java:1897)
at androidx.recyclerview.widget.RecyclerView$1.run(RecyclerView.java:414)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:874)
at android.view.Choreographer.doCallbacks(Choreographer.java:686)
at android.view.Choreographer.doFrame(Choreographer.java:618)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:860)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Caused by: java.lang.UnsupportedOperationException: Failed to resolve attribute at index 68: TypedValue{t=0x2/d=0x7f04005d a=-1}
at android.content.res.TypedArray.getDimensionPixelSize(TypedArray.java:716)
at android.view.View.<init>(View.java:4228)
at android.view.ViewGroup.<init>(ViewGroup.java:579)
at android.widget.LinearLayout.<init>(LinearLayout.java:211)
at android.widget.LinearLayout.<init>(LinearLayout.java:207)
2020-03-15 02:32:15.578 1779-1779/com.shatelland.namava.tv.debug E/AndroidRuntime: at android.widget.LinearLayout.<init>(LinearLayout.java:203)
I don't know why the class is unknown.
i can't find which layout has error because of this.

After long time searching i find the reason.
The Activity that contains the Fragment should set theme to Leanback
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setTheme(R.style.Theme_Leanback)
}

Instantiating MapBox before inflating the fragment layout cause Exception

I'm following MabBox tutorial at https://docs.mapbox.com/help/tutorials/android-navigation-sdk/ to make a simple navigation fragment that use the basics elements of it.
I already know that MapBox require to instantiate before inflating the View because I made it before on another Fragment to test it out where the fragment is part of a TabLayout component, however, in this one, there's only one Activity that loads the Fragment where I use the SDK and in this case it throws the same error that I fixed previously because I put it afterinflating the layout.
The errore that appears is this one:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.parkingclientapplication, PID: 14257
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.parkingclientapplication/com.example.parkingclientapplication.activities.MapDirectionActivity}: android.view.InflateException: Binary XML file line #8: Binary XML file line #8: Error inflating class com.mapbox.mapboxsdk.maps.MapView
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2817)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: android.view.InflateException: Binary XML file line #8: Binary XML file line #8: Error inflating class com.mapbox.mapboxsdk.maps.MapView
Caused by: android.view.InflateException: Binary XML file line #8: Error inflating class com.mapbox.mapboxsdk.maps.MapView
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
at android.view.LayoutInflater.createView(LayoutInflater.java:647)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:790)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139)
at com.example.parkingclientapplication.activities.MapDirectionActivity.onCreate(MapDirectionActivity.kt:15)
at android.app.Activity.performCreate(Activity.java:6975)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: com.mapbox.mapboxsdk.exceptions.MapboxConfigurationException:
Using MapView requires calling Mapbox.getInstance(Context context, String accessToken) before inflating or creating the view. The access token parameter is required when using a Mapbox service.
Please see https://www.mapbox.com/help/create-api-access-token/ to learn how to create one.
More information in this guide https://www.mapbox.com/help/first-steps-android-sdk/#access-tokens.
at com.mapbox.mapboxsdk.Mapbox.validateMapbox(Mapbox.java:165)
at com.mapbox.mapboxsdk.Mapbox.getAccessToken(Mapbox.java:77)
at com.mapbox.mapboxsdk.storage.FileSource.<init>(FileSource.java:234)
at com.mapbox.mapboxsdk.storage.FileSource.getInstance(FileSource.java:68)
at com.mapbox.mapboxsdk.maps.renderer.MapRenderer.<init>(MapRenderer.java:34)
E/AndroidRuntime: at com.mapbox.mapboxsdk.maps.renderer.glsurfaceview.GLSurfaceViewMapRenderer.<init>(GLSurfaceViewMapRenderer.java:33)
at com.mapbox.mapboxsdk.maps.MapView$5.<init>(MapView.java:294)
at com.mapbox.mapboxsdk.maps.MapView.initialiseDrawingSurface(MapView.java:294)
at com.mapbox.mapboxsdk.maps.MapView.initialize(MapView.java:137)
at com.mapbox.mapboxsdk.maps.MapView.<init>(MapView.java:100)
... 25 more
The code for the Activity is:
class MapDirectionActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_map_direction)
supportFragmentManager.inTransaction {
add(R.id.form_clientNavMenu, MapDirectionFragment())
}
//Logout action on custom toolbar layout
logout.setOnClickListener {
val intent = Intent(this, MainActivity::class.java)
startActivity(intent)
}
}
}
The code for the onCreateView method of the Fragment is:
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
Mapbox.getInstance(context!!, getString(R.string.access_token))
val view = inflater.inflate(R.layout.fragment_map_direction, container, false)
mapView = view.findViewById(R.id.mapView)
mapView.onCreate(savedInstanceState)
mapView.getMapAsync(this)
// Inflate the layout for this fragment
return view
}
I only wrote onCreateView method because I think the error could be in there instead on the rest of the code which is the same as in the link, but I could be wrong.

Set the method:
Mapbox.getInstance(this,getString(R.string.access_token));
Before the:
setContentView(R.layout.activity_map);
If you having this exception change code structure as follows.
i.e:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Mapbox.getInstance(this,getString(R.string.access_token));
setContentView(R.layout.activity_map);
mapView = (MapView) findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
mapView.getMapAsync(mapboxMap -> mapboxMap.setStyle(
new Style.Builder().fromUrl(Style.MAPBOX_STREETS)
));
}

Thanks #Tobrun for the answer, the problem was not that I missed the accessToken but I mixed activity and fragment layout so the components in one of them should be in the other. However, looking for the accessToken made me realize about other possible ones.

How to use both Kotlin Android Extensions and Databinding at the same time?

I want to make an Android project with Kotlin, so I build it with kotlin and Databinding. It's nothing wrong with it. But when I use Kotlin Android Extensions or Butterknife, the app I built from this project can not be used normally.
Here is my fragment class
class MainFragment: Fragment() {
private var stock: StockQuote? = null
override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View {
val binding: FragmentMainBinding = DataBindingUtil.inflate(inflater!!, R.layout.fragment_main, container, false)
binding.stock = stock
search_et.setOnFocusChangeListener { v, hasFocus ->
if(!hasFocus){
val newStock = ScrapingUtil.getQuote(search_et?.text.toString())
if(newStock != null){
stock?.name = newStock.name
}
}
}
return binding.root
}
}
I tried to use Butterknife at first but it didn't work, the View I want to bind would be null. Then I tried to use Kotlin Android Extensions, it threw an error at runtime
E/AndroidRuntime: FATAL EXCEPTION: main
Process: cn.mister.stockcalculator, PID: 30010
java.lang.RuntimeException: Unable to start activity ComponentInfo{cn.mister.stockcalculator/cn.mister.stockcalculator.MainActivity}: android.view.InflateException: Binary XML file line #10: Binary XML file line #10: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2736)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2807)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1604)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:191)
at android.app.ActivityThread.main(ActivityThread.java:6016)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:960)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:821)
Caused by: android.view.InflateException: Binary XML file line #10: Binary XML file line #10: Error inflating class fragment
at android.view.LayoutInflater.inflate(LayoutInflater.java:539)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139)
at cn.mister.stockcalculator.MainActivity.onCreate(MainActivity.kt:10)
at android.app.Activity.performCreate(Activity.java:6370)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1122)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2689)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2807) 
at android.app.ActivityThread.-wrap11(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1604) 
at android.os.Handler.dispatchMessage(Handler.java:111) 
at android.os.Looper.loop(Looper.java:191) 
at android.app.ActivityThread.main(ActivityThread.java:6016) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:960) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:821) 
Caused by: android.view.InflateException: Binary XML file line #10: Error inflating class fragment
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:782)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:835)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:374) 
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287) 
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139) 
at cn.mister.stockcalculator.MainActivity.onCreate(MainActivity.kt:10) 
at android.app.Activity.performCreate(Activity.java:6370) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1122) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2689) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2807) 
at android.app.ActivityThread.-wrap11(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1604) 
at android.os.Handler.dispatchMessage(Handler.java:111) 
at android.os.Looper.loop(Looper.java:191) 
at android.app.ActivityThread.main(ActivityThread.java:6016) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:960) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:821) 
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.EditText.setOnFocusChangeListener(android.view.View$OnFocusChangeListener)' on a null object reference
at cn.mister.stockcalculator.MainFragment.onCreateView(MainFragment.kt:23)
at android.app.Fragment.performCreateView(Fragment.java:2236)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:962)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1139)
at android.app.FragmentManagerImpl.addFragment(FragmentManager.java:1241)
at android.app.FragmentManagerImpl.onCreateView(FragmentManager.java:2236)
at android.app.FragmentController.onCreateView(FragmentController.java:98)
at android.app.Activity.onCreateView(Activity.java:5678)
at android.support.v4.app.BaseFragmentActivityApi14.onCreateView(BaseFragmentActivityApi14.java:41)
at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:68)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:754)
how can I fix it?

I found the answer at Kotlin Android Extensions and Fragments.
DataBinding doesn't matter, you should directly access search_et in the onViewCreated method

Runtime Exception in Preference Fragment

I have a preference fragment with the following files
preference.xml
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<EditTextPreference
android:defaultValue="0000"
android:key="#string/pin"
android:summary="Set Pin for Notes"
android:title="Password" />
</PreferenceScreen>
Preference Activity
public class PreferenceActivity extends AppCompatActivity {
#BindView(R.id.toolbar_settings)
Toolbar toolbarSettings;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_settings);
ButterKnife.bind(this);
setSupportActionBar(toolbarSettings);
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
}
and finally
Preference Fragment
public class PreferenceFragment extends PreferenceFragmentCompat {
#Override
public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
addPreferencesFromResource(R.xml.preference);
}
}
But here when the addPreferencesFromResources is called, I am getting a runtime exception.
Here is the log stack
Exception
02-21 22:23:36.574 8813-8813/in.snotes.snotes E/AndroidRuntime: FATAL EXCEPTION: main
Process: in.snotes.snotes, PID: 8813
java.lang.RuntimeException: Unable to start activity ComponentInfo{in.snotes.snotes/in.snotes.snotes.settings.PreferenceActivity}: android.view.InflateException: Binary XML file line #0: Binary XML file line #0: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2659)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2724)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1473)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6123)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:757)
Caused by: android.view.InflateException: Binary XML file line #0: Binary XML file line #0: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #0: Error inflating class fragment
Caused by: java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
at android.app.SharedPreferencesImpl.getString(SharedPreferencesImpl.java:225)
at android.support.v7.preference.Preference.getPersistedString(Preference.java:1601)
at android.support.v7.preference.EditTextPreference.onSetInitialValue(EditTextPreference.java:92)
at android.support.v7.preference.Preference.dispatchSetInitialValue(Preference.java:1517)
at android.support.v7.preference.Preference.onAttachedToHierarchy(Preference.java:1245)
at android.support.v7.preference.Preference.onAttachedToHierarchy(Preference.java:1257)
at android.support.v7.preference.PreferenceGroup.addPreference(PreferenceGroup.java:194)
at android.support.v7.preference.PreferenceGroup.addItemFromInflater(PreferenceGroup.java:126)
at android.support.v7.preference.PreferenceInflater.rInflate(PreferenceInflater.java:355)
at android.support.v7.preference.PreferenceInflater.inflate(PreferenceInflater.java:162)
at android.support.v7.preference.PreferenceInflater.inflate(PreferenceInflater.java:112)
at android.support.v7.preference.PreferenceManager.inflateFromResource(PreferenceManager.java:138)
at android.support.v7.preference.PreferenceFragmentCompat.addPreferencesFromResource(PreferenceFragmentCompat.java:432)
at in.snotes.snotes.settings.PreferenceFragment.onCreatePreferences(PreferenceFragment.java:12)
at android.support.v7.preference.PreferenceFragmentCompat.onCreate(PreferenceFragmentCompat.java:224)
at android.support.v4.app.Fragment.performCreate(Fragment.java:2246)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1377)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1650)
at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1906)
at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:3698)
at android.support.v4.app.FragmentController.onCreateView(FragmentController.java:111)
at android.support.v4.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:350)
at android.support.v4.app.BaseFragmentActivityApi14.onCreateView(BaseFragmentActivityApi14.java:39)
at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:67)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:777)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:727)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:858)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:821)
at android.view.LayoutInflater.inflate(LayoutInflater.java:518)
at android.view.LayoutInflater.inflate(LayoutInflater.java:426)
at android.view.LayoutInflater.inflate(LayoutInflater.java:377)
02-21 22:23:36.575 8813-8813/in.snotes.snotes E/AndroidRuntime: at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139)
at in.snotes.snotes.settings.PreferenceActivity.onCreate(PreferenceActivity.java:21)
at android.app.Activity.performCreate(Activity.java:6672)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1140)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2612)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2724)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1473)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6123)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:757)
I had a switch preference before the edit text preference and that worked fine. Once i replaced the switch preference with edit text preference, this error is thrown.
How do I fix this?

Can you try the code below?
strings.xml
<string name="pin_default_value">0000</string>
preference.xml
<EditTextPreference
android:defaultValue="#string/pin_default_value"
android:key="#string/pin"
android:summary="Set Pin for Notes"
android:title="Password" />
Android is trying to set default value but it is reading 0000 as an Integer and not as a String Main reason is that android:defaultValue is not directly handled as String. This way, to avoid this int to Stringconversion error, you must explicit use a String value (by using some string from strings.xml.
Note
You may need to clear your app data since that wrong default value may be stored in cached files already.