ForkJoinPool and Kotlin Coroutines As I understand it, by default, if you start a Kotlin Coroutine via launch or async it'll launch in CommonPool (or if you use GlobalScope). And CommonPool is a ForkJoinPool and that, by default, is in non-async mode so it executes tasks in LIFO order. That seems like a very bad choice for something like asynchronous web server applications where we'd want fair scheduling: we don't want the poor sucker who hit our web server first to wait for all calls that came later. However, Kotlin...

Kotlin/Andoid Studio - App crashing when e-mail is badly formatted Sorry - I'm very new to Kotlin and Android sdk, but I'm hoping that means this will be an easy question to solve! When using the register page for my app, the app crashes every time I try to register using an invalid e-mail address (For example: "test"), I have already created an .addOnFailureListener (visible at the bottom of my code below) - but I still receive an error saying "the email address is badly formatted". My app seems to crash before my "Toast.makeText" has a chance to address...

How to call static methods in fragment and activities? I have an api method call that is called either in activities our fragment, the problem is that I need to have two equal methods with only the type(BaseActivity our BaseFragment) changing like this: fun BaseActivity.callAPI(call: Call?, onSucceed: (T?) -> Unit) { callAPI(call, onSucceed, {}) } fun BaseFragment.callAPI(call: Call?, listener: BaseFragment.OnFragmentInteractionListener, onSucceed: (T?) -> Unit) { callAPI(call, listener, onSucceed, {}) } Is there a way to only have...

Repeat function to call data from server every second So if I press the Start button I want to repeat the function "fetchCarData()" every Second till I press the End Button. What's the best way to achieve this, is there any fancy Kotlin way of implementing such a thing? class CarDataSourceImpl(private val carDataService: CarDataService) : CarDataSource { //Live Data List that can be accessed only by this class private val _loadedCarData = MutableLiveData() //actual Live Data List observed by the Views override val loadedCarData: LiveData...

Kotlin: Lambdas, range, map, filter and reduce/fold Using the functions such as lambdas, range, map, filter and reduce/fold, calculate the sum of numbers between 1 and 1000 which are divisible by 5 or 3 and print the result.

How can I change Fragment UI elements asyonchrounsly with a Reactive Bluetooth subscription? I don't receive any errors or crashes from the following code but the Button and TextView simply don't change as I expect them to. I'm subscribing to a external Bluetooth device and I can monitor the state changes successfully when I connect and disconnect. The logs show this (see below). I initiate the subscription in my MainActivity but the Button and TextView are in a separate Fragment. How can I make this work? /* Buttons */ val homeFragment = HomeFragment.newInstance() /* Buttons */...

Iterating over list with lambda forEach Kotlin I have a list of 30 random numbers that correspond to 1 of 8 colours, and I need to iterate over the 8 colors(or 30 numbers) and find the number of times each colour occurs. I need to do this using lambdas and functional programming, so no traditional for loops. val iterator = colours.toList().iterator() iterator.forEach{ println("$it count: " + (numbers .map{a -> colours[a]} .count{it == ("$it")})) } The problem currently is my output for count is just 50,...

How to remove .kotlin_metadata in apk When I build android application with kotlin, apk size is increased. Inside the apk, many .kotlin_metadata files in both kotlin/ kotlinx/ folders. Is there any way to remove them from my apk?

unfinished stubbing detected during rxbinding observable why does mockito complain of unfinished stubbing in the following example: doReturn(Observable.just("cat")).whenever(mockedEditText).textChanges() textChanges() is an rxbinding method that returns a ConnectedObservable()

Callback of locationChanged in Mapbox Android How to implement the callback for locationChanged in Mapbox Android for Kotlin? I want to perform some operations on every location update of the user. I couldn't find anything in docs. Probably, it's really simple. Thank you,

ClassWithInstantRunDebug error in Android App I have recently change the OS from Linux to Windows and create a studio environment with the existing Android SDK used in Linux. But I am getting the below error continuously. I have tried the below solution, But didn't work File -> Invalidate Cache and restart removed .gradle and .idea folder from Project and rebuild. The error log is attaching with this java.lang.RuntimeException: com.android.build.api.transform.TransformException: java.lang.NullPointerException at...

How to mock a Bitmap using mockk without it affecting bitmap.compress in future tests How do I mockk a Bitmap without it breaking Bitmaps in future tests? Let's take the following simplified example... class FileHelper @Inject constructor(private val application: Application) { fun saveBitmapToTempDirectory(bitmap: Bitmap, filename: String, format: Bitmap.CompressFormat): File { val tempDirectory = File(application.cacheDir, "images").apply { mkdirs() } val file = File(tempDirectory,...

How to determine which cells in a RecyclerView are currently visible and drawn/rendered I'm making an app with a linear/vertical RecyclerView on a page and when someone enters the page, I want to know which is the last cell in my RecyclerView that is immediately visible **as we enter the page only (no scrolling)**and already drawn/rendered on screen to the user. I wanted to override LinearLayoutManager#onLayoutChildren and call <a...

Rxjava 2 on error is not called while unit testing Rxjava 2 on error is not called while unit testing . I am using kotlin with rxJava 2 . method @SuppressLint("CheckResult") override fun fetchFilms() { view.showLoader(true) disposable = getRetrofitInstance(false).create(API::class.java) .fetchFilms() .subscribeOn(io) .observeOn(main) .subscribeWith(object : DisposableObserver() { override fun onComplete() { }...

Calling class in swift from kotlin/native framework I followed the tutorial: https://kotlinlang.org/docs/tutorials/native/mpp-ios-android.html and successfully export a jar file for Android and a framework for iOS. After I want to implement something more complex. I uses Android Studio Kotlin with the codes below: Model.kt: package org.kotlin.mpp.mobile.BusinessLogic abstract class Model{ var _id:Long = 0 abstract fun...

Android native library (.so) - unsatisfied link error I have recently created and published an Android App bundle with compiled native libraries for all processors architectures. On most of devices everything is running ok. But on some of devices I can see this error in Crashlytics console Fatal Exception: java.lang.UnsatisfiedLinkError dalvik.system.PathClassLoader[DexPathList[[zip file "/system/framework/org.apache.http.legacy.boot.jar", zip file...

ArCore success floor find Is there a method, which is performed after a floor is found in ArCore? I tried to look for a solution, but I did not have success. I am looking for something like onSurfaceDetection()

How to create an interceptor for errors to make another call? I'm getting a 401, because token has expired, so I need to renew the token with another call and then do the call again, is there an easy way instead of doing : disposable = loginService.login( UserToLoginRequest( input_email_login.text.toString(), input_password_login.text.toString(), generateRandomDeviceInfo() ) ) .subscribeOn(Schedulers.io())...

Reject SDP: no suitable codecs What is Reject SDP: no suitable codecs? This error has occurred while accepting incoming SIP audio call. It's working fine If I call between my same two apps but not in between my app and other already developed apps. Can somebody help me with that?

When i'm try to logged in user by their google account then this log continuously printing. How can i solve this? i have a problem when i'm try to logged in user by their google account. after successfuly login this log continousoly printing. "I/BufferQueueProducer: SurfaceTexture-0-30436-0 queueBuffer: slot 1 is dropped, handle=0x943e8340" and when i logged out google account then it stopped. can anyone help me to solve this issue, because due to this issue i'm unable to check other usefull logs.my code is in Kotlin.

how to parse json array request in android using retrofit i want to just pass jsonarray request in kotlin(Android) using retrofit2 library i have search on internet also but i didn't get proper result i want to send this type of json array request {"teacher_id":"4","class_id":"5","attendance_name":[{"student_id":"34","attendance_name":"P"},{"student_id":"36","attendance_name":"A"},{"student_id":"38","attendance_name":"A"}]} i have see in log its shown proper request but in server side get null array interface APIInterface...

How the compiler finds objects in a file Is JVM unable to detect variables (in the same scope) below a variable? I.e., they can only detect variables declared before that variable. I'm just trying to gain an understanding of how the compiler finds objects in a file (and it's limitations): kotlin code fun main(args : Array) { var first: Int = second + 2 // Unresolved Reference: Second var second: Int = 1 var third: Int = 1 + returnTwo() // works fine } fun returnTwo(): Int = 2 So the compiler moves from top to...

Realm table is no longer valid to operate on open class Notification : RealmObject { var user: User? = null var labelNotif: String = "" constructor(intent: Bundle, context: Context) { ... val realmInstance = Realm.getDefaultInstance() ... realmInstance.executeTransaction { realm -> realm.copyToRealmOrUpdate(this) } realmInstance.close() } } This code work every time for me and for the most part of my users but there is also a large part of crash on copyToRealmOrUpdate line with error: "Fatal...

How to make a view stick on the keyboard in Android app.Whenever other views are clicked keyboard and the view showed be gone Whenever user clicks on a Textview which is present in a NestedScrollView should popup keyboard as well as TextInputLayout should be displayed above it.Whenever other views are clicked keyboard and the view showed be gone.

In my Fragment, onBackPressed is called before onCreateView is called I run Random test(Monkey test) and it found a crash regarding kotlin.UninitializedPropertyAccessException. I have lateinit var videoEditorView in my Fragment and it is initialized in onCreateView(). My onBackPressed() calls onRelease(). In my onRelease(): override fun onRelease() { super.onRelease(){ videoEditorView.release() } Problem is, sometimes, onBackPressed seems called before onCreateView() Is it occasionally happening? If so, is there any way to avoid this by adding...

Webflux - does jaxb can affect to performance of reactive application? I have webflux application which mainly parse xml and returns json response. Max xml size which app handles is about 9MB, just like json response. Problem is that my application throughput is only 16TPS! I think it's very low for reactive application. I spent a few days on debugging my application to discover what is wrong and I think JAXB is a bottleneck. I've tried few JAXB improvements like unmarshal from byteInputStream instead of StringReader etc. So, my question is, does jaxb isn't...

How to typesafe reduce a Collection of Either to only Right Maybe a stupid question but I just don't get it. I have a Set and want to output a Set with Arrow.kt.

Initializing a Kotlin function In the following code: private fun bindTestTextChanges(): Disposable? = viewModel.testText.subscribe { text -> selectAssetsView.setTestText(text) } Is the part after Disposable? code for initializing the function? Or does that code only get called when the function is called?

How to ignore single touch action before two fingers touch in android cusom view? I need scaling feature in my painting app, so I use ScaleGestureDetector, but when I perform two fingers touch action to zoom - before it triggers single touch action and draws something on Canvas, how can I check, that canvas is zooming now and ignore single touch action? override fun onTouchEvent(event: MotionEvent): Boolean { scaleDetector.onTouchEvent(event) event.transform(touchMatrix) val x = event.x val y = event.y when (event.action and MotionEvent.ACTION_MASK)...

Error after Parse query from local datastore I'm using Parse.com library and I want to query from local datastore if user lost access to internet (query on pinned items from previous app usage). Problem is that if use offline query it will not return List but weird AbstractList and I don't know how to convert it to ArrayList. Anyone had this issue? API call: fun getFilteredObjects(c: Context, searchQuery: String?, filteredObjectsCallback: (ArrayList?, ParseException?) -> Unit){ val q = ParseQuery.getQuery(OBJECT_CLASS)...