No field with the name mListener is found in Animation class Navigation Activity class NavigationActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelectedListener { private lateinit var appBarConfiguration: AppBarConfiguration override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_navigation) val toolbar: Toolbar = findViewById(R.id.toolbar) setSupportActionBar(toolbar) val fab: FloatingActionButton = findViewById(R.id.fab) fab.setOnClickListener...

Android getItemId() return the same id many times in recyclerview I'm trying to implement setHasStableId(true) in my chat application, when i override getItemId() method in my RecyclerView Adapter in this way override fun getItemId(position: Int): Long = filterItems[position].hashCode().toLong() The application tells me that the same item id is being returned several times. Items are notbeing duplicated in the list for user is everything ok but I'm getting this error. Two different ViewHolders have the same stable ID. Stable IDs in your adapter MUST...

I need class for this Json in Gson in Kotlin, how can get all strings method from result bject {1} response {9} status : ok userTier : developer total : 2161413 startIndex : 1 pageSize : 10 currentPage : 1 pages : 216142 orderBy : newest results [10] 0 {11} id : sport/2019/dec/20/maxime-vachier-lagrave-chess-france-top-player-clings-to-candidates-hope type : article sectionId [0] sectionName {0} webPublicationDate : 2019-12-20T120017Z webTitle : Chess: France’s top player clings...

What is the purpose of inner class in kotlin? I am new to kotlin. i am going through Nested class and inner class concepts in kotlin. Below is a example of nested class. fun main(args: Array) { val demo = Outer.Nested().foo() // calling nested class method print(demo) } class Outer { class Nested { fun foo() = "Hello world" } } which gives output as Hello world here is the example of inner class. fun main(args: Array) { val demo = Outer().Nested().foo() // calling inner class method print(demo) } class...

Why Exoplayer2.x buffers in FullScreen Mode I use exoplayer to stream live videos. When trying to make it fullscreen in another activity(with passing URL), I don't want to reBuffer the video again. Is there any way to continue playing without rebuffering? var intent = Intent(activity!!, FullscreenVideoActivity::class.java) intent.putExtra("url", url) view?.findNavController()?.navigate( R.id.action_liveFragment_to_fullscreenVideoActivity, intent.extras )

Simple Kotlin Data Save I am trying to make a simple Kotlin Class user for Android and i would like to save the username to keep it when closing and reopening the application import android.content.Context.MODE_PRIVATE import android.content.SharedPreferences class User (var username : String){ private val PREFERENCE_FILE_KEY = "AppPreference" private val KEY_USERNAME= "prefUserNameKey" private val sharedPref : SharedPreferences = activity?.getSharedPreferences(PREFERENCE_FILE_KEY, MODE_PRIVATE)...

lateinit property listener has not been initialized I am trying to add an onclick listener to a recyclerview item i however keep getting an error that states the listener has not been initialised, but it has been initialised, what am i doin wrong. Here is how my adapter looks like class ProductAdapter(private val productModel: List): RecyclerView.Adapter(){ private lateinit var listener: OnItemClickListener override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ProductView { val view =...

JSON String to Generic type known at runtime I'm looking to deserialize a JSON string in a Generic object. The type of my object is known at the execution. This is the object I want to deserialize : data class APIResponse( var list: List? = null ) So I created several classes that can correspond to the object in which will be in the list. My Retrofit GET return this : Single, this way I get my JSON String. This is what I've done fr retrieving my data and deserialize the JSON String : @SuppressLint("CheckResult") fun getJSON()...

Android test orchestrator no tests were found I am developing an Android application using Kotlin programming language. I am writing instrumented tests for my application. I am also using the test orchestrator to run my instrumented tests. But after the installation of the test orchestrator modifying the Grandle file, I cannot run the test in the Android Studio. I added the following configuration to the app.grandle file android { compileSdkVersion 29 buildToolsVersion "29.0.2" defaultConfig { applicationId...

How to bind MaterialButtonToggleGroup? *I'm using material design I have MaterialButtonToggleGroup with three buttons and to bind them *

RecyclerView Fragment onClick won't display Next Fragment I am workin on an app, the recyclerView makes a clicking noise which lets me know that the onClickListener functions. It just isn't displaying the next fragment. I really need help as to if I should use a FragmentManager and where I should put it if that is the case. HomeFragment import android.os.Bundle import android.view.LayoutInflater import android.view.View import android.view.ViewGroup import androidx.fragment.app.Fragment import androidx.lifecycle.ViewModelProviders import...

How to send MutableList<Point> from intent to another in kotlin I'm trying to send MutableList array list as Extra from Intent to another in kotlin. Declaring the list: private var thePoints: MutableList = mutableListOf() and here is how I add items to it: if (startStationPoint != null) { thePoints.add(startStationPoint) } And am using this method to send it to the other Activity: navigationActivity.putParcelableArrayListExtra( "thePoints", thePoints)...

Kotlin override "static" property is subclass I have an interface(it could be a class, doesn't matter) Record which has to be accessible like Record.size, without having an instance. As kotlin replaced static with companion objects, I have something like this: interface Record { companion object{ val size = 0 } } Now the real problem is when I want to have classes inheriting Record: RecordA and RecordB, which have some other value of size, and I want it to be accessible as Record.size as well. It is such a trivial...

BuildConfig is public, should be declared in a file named BuildConfig.java Seem to be getting this occurring error whenever I run my android application. The only way to get around it is by rebuilding the project and runs normally again. If anyone knows the reason for this will be much appreciated

Cannot resolve settings_container The Android official page says to create the preferences Activity this way: class MySettingsActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) supportFragmentManager .beginTransaction() .replace(R.id.settings_container, MySettingsFragment()) .commit() } }...

How to retrive data from firebase without specifing key? I want to retrieve data from my firebase database but the problem is there are more than one key that I can't specific in my query cause it can be changeable. for example let my database be: MYFIREBASEDATABASE.com/Users/UserId/date/hour/ARRAY_OF_NUMBERS(let's say 150 numbers) Where day and hour can be changeable but I want all the numbers under the specific UserId to put them in RecyclerView. I hope I did explained it clearly.

Android signature initVerify cause exception I created a server, which can respond to a client with random points. Server code private static void generateKeys() throws InvalidAlgorithmParameterException, NoSuchAlgorithmException { ECGenParameterSpec ecSpec = new ECGenParameterSpec(SPEC); KeyPairGenerator g = KeyPairGenerator.getInstance("EC"); g.initialize(ecSpec, new SecureRandom()); KeyPair keypair = g.generateKeyPair(); publicKey = keypair.getPublic(); privateKey = keypair.getPrivate(); } private static...

Are Xcode plugins cached or referred somewhere? I'm having a bit of a problem where running xcodebuild on the command line is giving me a warning that states "DVTPlugInManager: Required plug-in compatibility UUID BAB79788-ACEE-4291-826B-EC4667A6BEC5 for Kotlin.ideplugin (org.kotlinlang.xcode.kotlin) not present" The Kotlin plugin is one that I tried, decided I didn't like, and removed. In fact I've checked and confirmed that ~/Library/Application\ Support/Developer/Shared/Xcode/Plug-ins/ is completely empty. This isn't really a problem,...

How do I run code before calling the primary constructor? I am writing a class that contains two immutable values, which are set in the primary constructor. I would like to add a secondary constructor that takes a string and parses it to get those two values. However, I can't figure out a way to implement this in Kotlin, as the secondary constructor calls the primary constructor immediately, before parsing the string. In java, I would call this(a,b) in one of the other constructors, but Java doesn't have primary constructors. How do I add this...

Set Firebase notification through Android Studio button [Kotlin] [Android Studio] I'm trying to make an app to program Firebase notifications using the buttons in my app. Is there any way to programm notifications through it? Thanks!

How to update emit value for flux from context I have this class: @Service class StatusEventPublisher { private var myEmiter: FluxSink? = null private val flux: Flux = Flux.push { emiter -> myEmiter = emiter } fun publishEvent() { myEmiter?.next(Unit) } fun getFlux() = flux } There is a process which calls method publishEvent. I'd like to emit this for flux. This code is work, but I don't think it is the most correct way.

Is there a Kotlin equivalent of setReadOnly()? Is there an equivalent of Java function setReadOnly() for files in Kotlin?

Move FrameLayout from CardView to overlap it I'm trying to do this type of layout, the thing is that I cant displace the FrameLayout above the image like this image Code My output I want to displace 1º premio to be like the first image, how can I do it ?

Numerical pagination in Firestore I'm developing an Android game in Kotlin. As a part of it I would like to fetch a leaderboard of players from Firebase. I am trying to paginate it numerically (i.e. page 1: players 1-50, page 2: players 51-100, etc.) I've read that this is not possible, because Firestore doesn't support this type of pagination. Is this true? Thanks in advance for your help.

Benefits of declaring a sealed class as object Context I have this sealed class and each of its children: sealed class Section class SearchSection : Section() class FavoritesSection : Section() class RecommendationsSection : Section() class ProfileSection : Section() But I get a warning over each class declaration: Sealed sub-classhas no state and no overrite equals Which suggest me to declare them as: object ProfileSection : Section() Question What is the purpose of this? What are the benefits? Why I should write them as...

Opening a WhatsApp chat with a specific contact by clicking on a button in my app (Kotlin) How can I Open a Whatsapp chat with a specific contact by clicking on a button in my app? That's the code I use. It opens WhatsApp and let me search the contact I want to send the message to, but it doesn't open the WhatsApp chat with the specific contact number I gave it to. whatsappButton.setOnClickListener{ var con = itemView.context val textToShare = "*כח אדם*" val phoneNumber = blogPost.phone val sendIntent = Intent()...

Why use multipart to upload an image? I am currently developing an app in Kotlin that uses the face API of Azure. For this I need to send images to the server. I use Retrofit 2.7.0 for the REST requests. Whenever I google about sending an image with retrofit, I come across the @Multipart annotation. For example here or <a...

Meaning of cardinal in type conversions In Spring, the values passed to annotations have to be compile-time constant. In the following snippet, if I pass the value for the argument openTimeoutExpression with "\${circuit.breaker.open.timeout}" I obtain the following error: org.springframework.expression.EvaluationException: Cannot convert value '5000' to type 'java.lang.Long' at org.springframework.expression.common.ExpressionUtils.convertTypedValue(ExpressionUtils.java:63) ~[spring-expression-5.2.0.RELEASE.jar:5.2.0.RELEASE]...

KMutableProperty with &lt;A,B&gt; and &lt;A,B?&gt; I want to pass a KMutableProperty1 to a constructor. The problem is that sometimes I need to pass property like this: class PropertyHandler(val prop:KMutableProperty1) Foo("Asd", "asd@asd.com") PropertyHandler(Foo::name) PropertyHandler(Foo::email) At this case compiler said at PropertyHandler(Foo::email) : Required KMutableProperty1 Found KMutableProperty1 Is there a method to pass String & String? to this? thx Zamek

Hibernate @Filter on enum column type This is a similar question to this: Hibernate @Filter collection of enums But in that question it looks like the asker has an enum type of varchar on the database, which is working fine for me. My isue is when trying to use hibernate filter annotations on entity values that have an enum column type in the database. Let's say the enum type of the column is called "database_enum" Take entity:...