Code obfuscation in KMP I have some questions around the topic of obfuscation in Koltin Multi-platform: Is there any built-in approach of code obfuscation available for each target? If yes, is it enabled by default for all targets? If no, what are the solutions for obfuscation of each target? 1 post - 1 participant Read full topic

Weird Coroutines and If-else Behaviour fun main() = runBlocking { var TEST = 8 var CHECK = 2 if(CHECK == TEST) { println("CHECK == TEST") } else if(CHECK < TEST) { CoroutineScope(Dispatchers.IO).launch { println("CHECK < TEST") } } else if(CHECK > TEST) { println("CHECK > TEST") } } <a class="lightbox" href=""...

Allow emojis to be used as variable names It would be cool if this was implemented i think 1 post - 1 participant Read full topic

Cinterop using cpp-library in gradle I am developing a multiproject in gradle using monorepo. Several projects are Kotlin/Multiplatform, another project is cpp-library. I want to pull my cpp-library artifacts into one of the Kotlin/Multiplatform projects using cinterop. Is it possible to have a C library in a separate gradle subproject and then access it via cinterop for the nativeMain implementation? Best regards Kristoffer 1 post - 1 participant <a...

Coroutine delay never finishes I am faced with a strange situation within a coroutine: I basically have this simple coroutine: runBlocking { launch { repeat(3) { println("running first... $it") delay(500) } } } println("runBlocking ended") Which runs fine, just printing: running first… 0 running...

Coroutines/Flow: keeping track of many concurrent 'sub-states' I want to: track many entities which publish their individual state asynchronously (perhaps they could emit through a MutableSharedFlow or Channel) relate their state to some asynchronously changing global state, in order to compute a secondary state for each of these entities I want to observe these secondary state changes, ideally through collecting a Flow. The problem is perhaps a bit too abstract, so I’ve confabulated a toy example. Suppose that we are tracking the objective feeling of...

Getting Line numbers from Android Studio Editor HI, We are developing Android apps using Android studio and writing all our code using the Kotlin Language. I am using debug lines in my code like this Log.d(Constants.BTH1, “cmd Empty - 132”) Where the TAG is a description picked from the Constants Class. The Tag has a number that I would like to be the Android studio editor line number. Obviously each time I change the code the line numbers change, so at the moment the line number only gives me a rough idea where that line of code is. We...

Using Kotlin named parameters constructor from Java When incrementally introducing Kotlin to an existing Java codebase, is there any way to make use of Kotlin named parameters from Java? I know that the Java language doesn’t support named parameters, but is there any kind of workaround? Something that could generate Builder-pattern code based on the Kotlin constructor with named parameters. Then Java client code could use this Builder pattern code to construct instances of the Kotlin data class. 1 post - 1 participant...

Android 12 issue while capturing an image using camera We are facing the problem while capturing an image using android 12 and it is working fine in our all other android versions, Specifically we are not getting the data part or the URI while coming back from capturing an image. Any help will be appreciated here. 1 post - 1 participant Read full topic

Access native platform apis in KMM on Windows Hello! According to this answer Kotlin IOS/Android Mutliplatform Hands On tutorial: Unresolved reference: platform - Stack Overflow is it not possible to access and code with native apis like the swift ones on Windows but only on macOS. I understand that to code in Swift you need to use macOS but does that also apply for the native code in the iosMain folder in the shared module? Is...

How to ignore a function on a certain platform Hello, is there a way to ignore some function for a (native) module in kotlin multiplatform? For example, in my project I use a builder pattern to create objects. public interface Item { ... public class Builder public constructor() { ... build(): Item ... } I also had a function that builds objects directly: public inline fun Item(block:Item.Builder.() -> Unit): Item = Item.Builder().apply(block).build() } On the native side, I get the following error when...

What is the kotlin version of out keyword for arguments? as far as I know, the arguments can’t be declared out’s because they are val’s, hence readonly, but is there a substitute method for the out keyword in java for kotlin other than writing wrappers for every class? Also, if the only way to overcome this is writing wrappers, wouldn’t it better to just integrate it into the language at this point? 1 post - 1 participant <a...

SharedFlow with DROP_OLDEST onBufferOverflow - is there a way to detect buffer drops? I have a SharedFlow configured to drop the oldest buffer if it is full. For diagnostic purposes, I’d like to be able to detect when a buffer is dropped. However, I could not find any such callback. Is there a way to accomplish this? 1 post - 1 participant Read full topic

KotlinLab update I like to announce that I improved KotlinLab,GitHub GitHub - sterglee/KotlinLabSimple: A MATLAB-like scientific scripting... A MATLAB-like scientific scripting environment for Kotlin, a simpler Kotlin only version of KotlinLab. Java 16 or newer is required to run KotlinLabSimple -...

Assertion failures on application startup Getting a bunch of messages like this when my JVM application starts: * java.lang.instrument ASSERTION FAILED *: "!errorOutstanding" with message transform method call failed at line: 872 * java.lang.instrument ASSERTION FAILED *: "!errorOutstanding" with message transform method call failed at line: 872 * java.lang.instrument ASSERTION FAILED *: "!errorOutstanding" with message transform method call failed at line: 872 * java.lang.instrument ASSERTION FAILED *:...

Why no shorthand for safe index access I would like to know the reason why don’t we have in Kotlin shorthand for safe index access? In Typescript, we could have: const a: string[] | null = null; console.log(a?.[0]); In Kotlin, we must use normal method name: val numbers: List? = null numbers?.get(1) 1 post - 1 participant Read full topic

Return a String inside the companion object function inside the CoroutineScope In the MainActivity in have a companion object function which consumes the variable outside the function. In the functioni would like to return the data as string inside the CoroutineScope. Here is the code:- class MainActivity : AppCompatActivity() { private var data = “myName” override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val data = getMyOuterValue() Toast.makeText(this@MainActivity, data,...

Kotlin compiler plugin, Kotlin resolution encountered a problem while analyzing KtClass I found that when I tried to develop IDEA plugin using the Kotlin compiler plugin, I implemented a SyntheticResolveExtension, and since there was no documentation, I had to try it by debug, for example, in the following I wanted to get KtClass by KtFile, which was easy, but when I got annotations on the class, I found that an exception was thrown: Kotlin resolution encountered a problem while analyzing KtClass It’s work fine: <a class="lightbox"...

Compiler error: smart cast is impossible I have two Kotlin classes in the same package: Foo.kt: data class Foo( val map: Map? = null ) Bar.kt: class Bar { init { val foo = Foo() if (filter.map != null) { val value = filter.map["some_key"] // IDE shows successful smart cast here } } } Then trying to compile only one class Bar.kt: kotlinc Bar.kt -d output Class Foo.kt resides in the same package, but nevertheless I’m getting the following compiler error: error: smart cast to 'Map' is...

Export KMP library to be used by native JS projects Hello everyone. How should I set up my build.gradle(:common) and what Gradle task should I use to be able to export my KMP library to be used by native JS or TS projects? Also, where in the folder structure will the output of this Gradle task be generated? I have already successfully set up the JsExport annotation. The code for the JS part of the build.gradle(:common) is below. I have tried several combinations, but can’t get it right. js(IR) { browser()...

Issue with Kotlin to JNI I’ve got a project where I’m trying to call a c++, as a dll on Windows, from java/kotlin. I got things working with Java, but since I love kotlin, I wanted to switch but I’m running into a lot of issues. The latest issue looks like a problem with the execution returning from the jni layer. Here is my kotlin class: import java.lang.IllegalStateException class Sterling constructor() { init { try { println("Loading library") System.loadLibrary("Sterling")...

Deploying a Kotlin Full-Stack Application on Heroku Hi. I am a newcomer to full-stack development. I chose Kotlin as my language to start because I was already familiar to it, and apparently Kotlin provided a wonderful tutorial on how to make a full-stack web app with itself. However, I am very confused on how to deploy my application to Heroku, especially the part using database – because the app itself...

When implementing Comparable overriding equals and hashcode is must? Whenever I implement Comparable Interface then should I have to override equals() and hashcode(). Let Suppose, I have to use Priority Queue and I have custom class. So to use Priority Queue I have to implement Comparable. But my confussion is It might have two different order and it basically depends on Priority Queue’s Implementation. CASE 1 → If Priority Queue internally uses == to compare CASE 2 → If Priority Queue internally uses compareTo to compare CASE 1 and CASE 2 will return...

Oodbms for kotlin backend/desktop please can you recommend me an oodbms to use with kotlin backend/desktop? do you know any? 1 post - 1 participant Read full topic

Kotlin multiplatform mobile Unresolved dependencies/references Hello kotlin community. I’m using Android Studio Bumblebee 2021.1.1 Patch 2. I’ve created a kmm project via File->New Project->Kotlin Multiplatform App for Android and iOS. My project has buildSrc, androidApp, shared, iosApp modules. buildSrc module: here the build.gradle.kts from buildSrc: plugins {

kotlin-dsl

} repositories { mavenCentral() } And Dependencies.kt from src/main/kotlin: object Versions { const val appVersionCode = 1 const val appVersionName = "1.0"...

Lateinit primitive types I am sure this has been asked before, why no lateinit primitive types? However, I am just confused with the answer that lateinit primitives are technically impossible From what I know the null value is used as uninitialized markers for object types underlyingly. Why can’t we do the same with primitives using boxed primitives (Integer instead of int)? We are able to do Int? but not lateinit var: Int why? 1 post - 1 participant <a...

Cancel blocking function after timeout without 'select' I am trying to execute a blocking function (accepting incoming TCP connections) from the main thread. For the sake of simplicity, let’s just say that this function returns after server.accept() in the following code returned 100 times: fun blockingFunc(server: ServerSocket): Int { var numSockets = 0 repeat(100) { runCatching { server.accept() numSockets++ } } return numSockets } Executing the function like this will obviously block...

Appending to a text file with FileWriter Hi there, In the following example using FileWriter, two lines are appended to a text file using both the .write() and .append() methods, when the context mode is set to APPEND (true)… FileWriter( "test_file2.txt", true ).use { out -> out.write("Appended Line\r\n") out.append("Appended Line\r\n") } What’s the difference between .write() and .append() in this case? I assume both methods would fail to append if APPEND mode were set to false? If they both perform the same, why do both...

Native-looking Windows GUI controls (Win Forms) in Kotlin? Hello All, Is there anything in Kotlin that can give me similar “native looking” GUI controls when creating Windows desktop programs, such as those found in Visual Studio when using C#? See screenshot for sample Windows controls. I like the idea of Kotlin for Android and back-end Web development, but Visual Studio makes it very easy to quickly throw together a desktop form and write some code behind the controls. A Windows program should look like a Windows program, not a rudimentary...

Appending to a text file with FileWriter &amp; bufferedWriter Hi All, In the following example using FileWriter, two lines are appended to a text file using both the .write() and .append() methods, when the context mode is set to APPEND (true)… File("test_file2.txt").bufferedWriter().use { out -> out.write(("Line 1\r\n")) out.write(("Line 2\r\n")) } FileWriter( "test_file2.txt", true ).use { out -> out.write("Appended Line 3\r\n") // append works here out.append("Appended Line 4\r\n") // append works here too! } Output ----------- Line...