Expecting member declaration Getting “expecting member declaration” when compile this simple android app. package com.example.buttonone import androidx.appcompat.app.AppCompatActivity import android.os.Bundle import android.widget.Button import android.widget.TextView import kotlinx.android.synthetic.main.activity_main.view.* class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) } var but1 =...

Why class function print() returns empty list? Hello, I am new to this forum. And I am also new to Kotlin. I don’t understand why the print function returns an empty list? For all I know, intList should have a class scope, not a function scope. Thank you for the answer. class addIntList() { val intList = mutableListOf() fun addInt(newInt: Int):addIntList { intList.add(newInt) print(intList) //this does not return empty list return this } fun print() { print(intList)//this returns empty...

Typed Source Code Bug TypedCodeAndDownloaded.zip (1.1 MB) For some reason I’m having a problem displaying Washington. There is a bug in the code. I have attached screen-shot of the two outputs when debugging - one in the source code that I typed in and the other downloaded. <a class="lightbox"...

Override @Step annotation (Allure) I am overriding @Step annotation (Allure) but unnecessary data appears in reports infix operator fun String.invoke(script: ()-> T): T = invokeAllureStep(this, script) @Step("{nameSteps}") @Suppress("UNUSED_PARAMETER") private fun invokeAllureStep(nameSteps : String , runScript : () -> T) = runScript() Why is it so? 1 post - 1 participant <a...

Windows BLE Api support As multiplatform is there any chance to get lib for using ble devices at Windows platform? 1 post - 1 participant Read full topic

Compile time checked intialization in inline functions Not sure if i’m using the right word, but by compile time checked initialization I mean this: // this compiles fun main() { var x: Int x = 10 println(x) } I would like the language to support a case like this: // this doesn't compile fun main() { var x: Int unsuspendable { x = 10 } println(x) } inline fun unsuspendable(block: () -> Unit) = block() The purpose of unsuspendable is we have large blocks of code in a suspend function, and we basically want to...

Why does is this code executed faster in a thread pool with 1 thread compared to one with more I’m currently starting out with coroutines and using them with spring webflux. I implemented an IO heavy endpoint but it seemed to get slower after my reactive implementation. Because of that, I tried something with coroutines that confused me even more. val scope = newFixedThreadPoolContext(2, "exampleThreadPool") @OptIn(ObsoleteCoroutinesApi::class) fun main() { runBlocking { val tasks: List Unit> = (0..10_000).map { { runTask() }...

Get multiple object instances at runtime via reflection Not sure whether it’s been discussed (didn’t find related threads in this forum). My use case is that I define some nested data structure (using data class) and some of them is declared as object. Then I use jackson to serialize/deserialize it for persistence. When I deserialize an instance of this data type, I realize those object declarations are not really singletons and their heap id is different. I could workaround this by making those object as data class but maybe it’s worthing...

Data class doesn't not use overridden method from sealed class Hello! I have a sealed class, DeliveryOption, where I override the toString method, but when I call it from Guy or Dispatcher it looks like it’s not overridden and returns the base implementation of toString. Why is it not calling the override one? sealed class DeliveryOption { abstract val id: Int abstract val name: String override fun toString(): String = name data class Guy( override val id: Int, override val name: String ) : DeliveryOption()...

Kotlin Bytecode Does the Kotlin compiler generate it’s own bytecode, before compiling down to a supported language (e.g. Java Bytecode or JS). I’m not asking how Kotlin and Java interpolates, I’m asking if Kotlin does (or is able to) generate a bytecode of it’s own, that keeps all Kotlin features (like objects, data classes) in it’s pure state, instead of compiling them into something that can be understood by Java. If yes, how would one go about finding it, because I can’t find anything like this in the...

Running dynamic number of child coroutines in parallel with cancellation Let’s say I have following code: interface Process { suspend fun run() } class ParallelProcess(initialChildren: List): Process { val children = mutableListOf(initialChildren) override suspend fun run() { if(!isActive()) throw IllegalStateException() // Run all the children here and wait for them // including the one that may have been added // while this is running. markInactive() } fun...

How exactly Any is being compiiled? Looking at common source of class Any, it seems there is no implementation of equals, hashCode and toString, how exactly does this work. where is the actual implementation public open class Any { public open operator fun equals(other: Any?): Boolean public open fun hashCode(): Int public open fun toString(): String } 1 post - 1 participant Read full topic

The documentation of Kotlin Hello I wanted to say that there is a problem in kotlin documentation.There is not left side of the screen for navigating, I don’t know what is the cause of this situation but I still can’t reach the page.please the team who is liable for documentation solve the problem.you can check this link Kotlin docs | Kotlin 1 post - 1 participant <a...

Please someone help me with code on how to upload and retrieve pdf, jpg and docx files from firebase using kotlin. on android studio Please I have had enough trouble getting help from the entire google searches and Youtube. I am new into Kotlin and I have a school project that requires this feature. please someone help with this . thanks in advance. 1 post - 1 participant Read full topic

Problem in check exercises in atomic kotlin Course Hi, I am trying to go ahead with the atomic kotlin book and do the exercises using the Edu Tools plugin. I will get this error after writing the exercise and hitting the check button. I could not solve this problem by searching please help. Build file '/home/meysam/IdeaProjects/AtomicKotlin/build.gradle' line: 28 A problem occurred evaluating root project 'AtomicKotlinCourse'.

Could not find method compile() for arguments [org.jetbrains.kotlinkotlin stdlib jdk81.5.20] on object of type...

Feature Request: Constructor parameter default value when receiving null input Hi there. I am in the process of converting a large Java code base to Kotlin, and I’ve run into an issue that makes this transition less than smooth. I’d like to suggest a small change to how class constructors work, particularly for data classes. As an example, I have a Java class like this: class MyClass { String name; List addresses; public MyClass(String name, List addresses) { this.name = name == null ? "" : name this.addresses = addresses == null ? Collections.emptyList()...

Ktor - Error Handling for respondTextWriter I’m developing a REST service that uses Ktor. I’m wanting to use call.respondTextWriter to send out json responses. Whenever I run into an error before fully writing the response, I notice that I still get an OK HTTP response code, but the json data I’m writing doesn’t get fully written. Is there a way to send an error http status code instead of OK if an exception happens inside respondTextWriter? Expected response: 200 OK {“response”: [“first”, “second”, “third”]} When an exception...

Image is not reflected in the recyclerview when I just want to update first name, last name and age Hi guys I’m working on a database with room in which I save an image and I can also update it, to show the image I am using a recyclerview, the problem is that when I only update username, last name and age,The image does not appear in the recyclerview. class UpDateFragment : Fragment() { private var _binding: FragmentUpDateBinding? = null private val binding get() = _binding!! private val arg by navArgs() private val mUserViewModel by viewModels() var stringPath: String...

[webpack-cli] Invalid configuration object Hi. I am having problems to run a completely new Kotlin/JS-React project created with IntelliJ. Despite the successfull build, I am getting a webpack-cli error complaining about invalid configuration. 074735: Executing task 'browserProductionRun --continuous'... Starting Gradle Daemon... Gradle Daemon started in 2 s 8 ms

Task :kotlinNodeJsSetup SKIPPED

Task :packageJson

Task :rootPackageJson

Task :kotlinNpmInstall

warning workspace-aggregator-d23f4bbc-3257-43a8-b0ed-b2a2f619db62 >...

Best kotlin course for beginner? As a beginner with having no background of programming language. Is it ok starting with kotlin? What is best course for beginners ? 1 post - 1 participant Read full topic

Trouble having the correct type import java.util.*; import javax.swing.plaf.basic.BasicBorders import kotlin.collections.ArrayList class Robot(val name: String) { var strength: Int = 0 // 1 var isAlive: Boolean = true // 2 infix fun attack(robot: Robot) { // 3 val damage = Random().randomDamage(strength) // 4 robot.damage(damage) } private fun damage(damage: Int) { // 5 val blocked = Random().randomBlock() if (blocked) { report("Blocked attack") return } // 6...

Are there some documents about pseudo? Hi all, I found Kotlin use pseudo as “IR” in front end. I’m confused about why kotlin uses it and waht is pseudo. Is there any documents dedicated to the Kotlin pseudo? Thank you in advance! 1 post - 1 participant Read full topic

Data class with 32+ properties code coverage problems Hello! I am a student and while studying Kotlin I created a data class with long list of properties, for convinience I added default values for each property. After that I decicded to test this default behaviour. While testing I encountered a problem with jacoco test coverage: If data class has = 33 properties with default values - jacoco shows only 50 % on branches coverage: data class TestDataNotOk( val val1: Long = 0, val val2: Long = 0, val val3: Long = 0, // ... val 4 -...

Announce of a new Kotlin based project project I like to announce the creation of a new Kotlin based project: GitLab ΑΣΤΕΡΙΟΣ ΠΑΠΑΔΗΜΗΤΡΙΟΥ / KotlinLab A user-friendly MATLAB like scientific programming environment based on Kotlin 1 post - 1 participant <a...

filterIsInstance function I didn’t understand the “refied” type parameter of “filterIsInstance” function when I read the documentation because shouldn’t the “refied” used inside inline function when we need to access type parameter at runtime? Link: filterIsInstance - Kotlin Programming Language<a class="lightbox"...

Why !. are required, as the field is never null? I wonder, why Kotlin compiler insists on placing !! after itemGroup in the following code, at it looks obvious (at least to me) that the value of itemGroup is never null: val itemViewsList = mutableListOf() val viewGroupQueue = java.util.LinkedList() var itemValue = 0 // Collect text items using breadth first algorithm var itemGroup: ViewGroup? = this do { for (index in 0 until itemGroup!!.childCount) { val item =...

Kotlin.Unit error Guys am a beginner and i can’t undertsand why; when i run this code i get “Kotlin.Unit” message under the solution !! i would really appreciate any helpp thankss !! Code : fun main() { val coin1 = flippingCoins() println ("Side : ${coin1.side} ") println (" ${coin1.result()}")} // main class flippingCoins { var side = (1..2).random() fun result() { if (side==1) println("ur coin landed tail ") else println ("ur coin landed head ") }...

Typed In Source Code Incorrectly - Employee Class This the code I’ve typed it and have problems with. I’ve included a copy of the original as well as what I’ve typed in. This is the code I’ve typed in: class Company( val name: String) { private val departments: ArrayList = arrayListOf() operator fun plusAssign(department: Department) { departments.add(department) } operator fun minusAssign(department: Department) { departments.remove(department) } val allEmployees: List get() = arrayListOf().apply { departments.forEach{ addAll(it.employees)}...

Anonymous type constructions There have been discussions on tuple and union types at various locations and the Kotlin Features Survey #2 also contains these proposals. The purpose of this topic is NOT: To continue the discussion on whether they should be added to the language or not. In fact, I’m also not a fan of complex languages which allow several different ways to reach the same goal and since such...

Changing getter names globally (compiler options) Modern Java does not use JavaBeans getter name conventions (at least for Record types). Is there any compiler option or compiler plugin, so that all getters names be generated w/o noisy get-prefix: I want size(), not getSize() for all classes. As you understand JvmName is not an option at all as it is terribly verbose and noisy. Per-class annotation would be better (if there is one), but global compiler option would be even better… 1 post - 1 participant <a...