Android Studio unresolved reference. Project compiles After upgrading Android Studio, a project with no issues started showing issues in the editor. I have lots of Unresolved Reference errors. Anything under the support libraries (support-v4, support-v7). In the screen capture above, anything showing in red isn't resolving and showing as an error. I am also using Lifecycle components and Room database. They seem to have issues as well. Looks like interfaces can be...

How to get the type of an instance of javax.lang.model.element.Element I'm following Hello World of Annotation Processing in Kotlin and KotlinPoet's documentation and am trying to implement a generic builder for Kotlin. I'd like to generically create a method for every field in an annotated data class and give it's argument the same name and type of the field. The problem is that I...

Initialize a class with default values when one parameter is a class kotlin 1.2.60 I have the following data classes and I want to initialize them with default values. However, I am unsure how can I initialize the Harddisk when its a class. I have tried do the following, but this will create a new HeadDisk object, not something I want: data class HeadDisk(var size: Float, var manufacturer: Manufacturer) data class Computer(var speed: Float = 0F, var screenSize: Float = 0F, var hardDisk: HeadDisk...

Kotlin does not understand ViewModelProviders.of(activity ?: fragment) Inside my Fragment I initialize a ViewModel using ViewModelProviders. I want it to take its Activity if not null, otherwise itself (Fragment). private val viewModel: MainViewModel by lazy { ViewModelProviders.of(activity ?: this).get(MainViewModel::class.java) } None of the following functions can be called with the arguments supplied. of(Fragment) defined in androidx.lifecycle.ViewModelProviders of(FragmentActivity) defined in androidx.lifecycle.ViewModelPro It seems...

'when' expression must be exhaustive error when using adapters I would like to do something like this: class MyPagerAdapter : PagerAdapter() { override fun getItem(position: Int) = when(position) { 0 -> Fragment0() 1 -> Fragment1() } override fun getCount() = 2 } I am sure that the adapter contains only 2 items, so getCount() simply returns 2. But it shows an error message said that 'when' expression must be exhaustive, add necessary 'else' branch. I understand that I can add an else to solve it, but it's really ugly to...

State in Ktor Intercepters I am following instructions on this help page: https://ktor.io/advanced/pipeline/route.html They give thhis example: ``` fun Route.routeTimeout(time: Long, unit: TimeUnit = TimeUnit.SECONDS, callback: Route.() -> Unit): Route { // With createChild, we create a child node for this received Route val routeWithTimeout = this.createChild(object : RouteSelector(1.0) { override fun...

Implementing flash for camera2 api android? I am new in camera2 api. i want to implement front and back flash in camera2 when capturing. i can make sure that the front or back camera have or have not flash. (its not a flash light app, its a camera app) fInfoForFlashBackFront= mCameraCharacteristics.get(CameraCharacteristics.FLASH_INFO_AVAILABLE); And implementing flash. //Implementing Flash private void setFlash(CaptureRequest.Builder requestBuilder) { Log.d(TAG, "onCreate: setFlash called "); Log.d(TAG,...

Overriding equals in Kotlin I'm learning Kotlin by reworking a small compiler I wrote in Java. CS implements kotlin.CharSequence. The essence of it is here: class CS (val sequence: CharSequence = "") : CharSequence { ... override get/length in interface CharSequence override fun equals(other: Any?): Boolean = (this === other) || ((other is String) && this.sequence.equals(other)) } The compiler objects to CS("hello") == "hello" as: Operator '==' cannot be applied to 'CS' and 'String'. It has no...

JDBI: querying a string column with kotlin I have a column title in a SQL table myTable. Using Kotlin and JDBI, how would I go about getting all the distinct entries in this table? This is what I have tried so far: val jdbi = Jdbi.create("...url", "...user", "...password") fun getTitles(): List = jdbi.withHandleUnchecked { handle -> handle.createQuery("select distinct(title) from myTable;") .mapTo(String.javaClass) .list() However, this gives me the following exception: A bean, Companion was mapped which...

How to getting value from Serializable class in kotlin? I have a fragment which is handling objects. so i need to send the values Instance to OnCreateview() so i want to convert my serializable form, so i create these class with getter/setter BeanDemo.kt class BeanDemo : Serializable { var MyAppDatabase: AppDatabase ? = null constructor() { } //secoutry constructor constructor(appDatabase: AppDatabase){ this. MyAppDatabase = appDatabase Log.d("appDatabase : Bean", "appDatabase$appDatabase") }...

How to achieve buttonX.setOnClickListener(this) in KOTLIN? I want to bind "this" context to listener in kotlin

Best Practise dual-pane in Android using only 1 activity and two fragments in Android Introduction Setting up a two pane application with two Activities and two possible fragments is discussed in several tutorials, see e.g. the tutorial from Lance Gleason. ALso the stubb code from Android Studio uses the kind of implementation. The problem The problem is that all tutorials only cover the static implementation method (using Fragments in XML) or...

Unable to create a JAR of my JDA project because of pom dependency I have a Kotlin project with JDA API which I need to deploy on Heroku environment. To achieve that I created a JAR task in my build.gradle file. jar { baseName = 'discord-stats-bot' version = 'v1' manifest { attributes('Main-Class': 'com.vchernogorov.discordbot.BotKt') } from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } } } But I was unable to build this JAR file because of the following error. 160203 vchernogorov $...

LiveData observer not getting triggered in Kotlin I am using LiveData with Kotlin in my project. I have been facing an intermittent issue wherein the Observer attached to a MutableLiveData object is sometimes not getting triggered. The Observer is attached in the activity onCreate(), (with the Activity as the Lifecycle Owner) over the LiveData object in the ViewModel. ViewModel instantiation: mViewModel = ViewModelProviders.of(this).get(MyViewModel::class.java) Setting the observer: mViewModel.mGoogleDirectionResponse.observe(this,...

How to keep package-level kotlin functions in proguard? I declared a package-level function as utility in my library and I want to use it in my main app. My issue is that I am not able to keep it from code obfuscation using proguard (and consequently use it in my main app). My file it.blabla.util.Extensions.kt fun foo(context: Context, action: String) { ... } I already tried to keep it in proguard using: -keep class it.blablabla.util.UtilPackage.** { *; } or -keep class it.blablabla.util.** { *; } but none of these is working. In my...

How pass to module of Dagger parameter action: (() -> Unit) for repeat request after lost connection I want check internet connection use ConnectivityInterceptor and passed parameter action: (() -> Unit) to module of dagger for repeat call request after connection was lost, how can I do it? @Module class NetworkModule { private fun getOkHttpClient(context: Context, action: (() -> Unit)): OkHttpClient { return OkHttpClient.Builder() .hostnameVerifier { s, sslSession -> true } .connectTimeout(TIME.toLong(), TimeUnit.SECONDS)...

Koin Android Test I have a problem with Koin & "androidTest". Because androidTest starts the Application i don't need to start Koin by myself in the test. Now i need to inject a mock service. The problem is, that i inject inside of a method with get() inside of a singleton class and this is not working via constructor injection because the injected object can have different implementations. My idea was to declare what i need this way: declare { factory(override = true) { mockWebservice } } But...

kapt generated code not available during compilation phase I have written a code generator using kapt, and am using it in a project compiling kotlin with maven. I find that the kapt generator is invoked after Kotlin's compile phase, which prevents me from using the generated code within kotlin in the same project. However, if I reference the generated classes from within Java in the same project, it works fine. This is because the java compilation phase comes after kotlin's generation phase. I've specified the kapt goal before Kotlin's...

ArrayIndexOutOfBoundsException in kapt I get an ArrayIndexOutOfBoundsException, when I try to build my project with dagger 2, Kotlin Coroutines and Java 8. The problem doesn't arise, when I use Java 9 or Java 10 (on Java 11 another problem occurs but that's another question). I created a <a...

Kotlin secondary constructor with generic type In java I can achieve two constructors like public TargetTitleEntryController() { } public TargetTitleEntryController(T targetController) { setTargetController(targetController); } I want to convert it to Kotlin class TargetTitleEntryController () with the secondary constructor. I don't know how to declare with generic type like Java counterpart.

Kotlin Async vs Launch Kotlin_version = '1.2.41' I am pretty new to Kotlin. I would like to know what's the difference between async and launch. Especially in the following code import kotlinx.coroutines.experimental.async import kotlinx.coroutines.experimental.awaitAll import kotlinx.coroutines.experimental.delay import kotlinx.coroutines.experimental.launch import kotlinx.coroutines.experimental.runBlocking fun main(args: Array) { runBlocking { (20..30).forEach { launch{...

The fastest way how to check how many words in string array is in the correct place I have a string: The quick brown fox jumps over the lazy dog And a random method, which are mixing these words in the array. brown jumps over The lazy fox quick the dog What is the fastest way to check how many words and which ones are in the correct place using java or kotlin ?

ANDROID - doubts like fingerprint without sensor I did a lot of research and could not find what I need. I need to make a fingerprint with devices that do not have fingerprint sensors, I was wondering if I had the touch screen or the camera ... Can there be any way I can do that ?? Some library that you indicate?

How to implement a circular RecylerView / ListView using any CircularLayoutManager I want to make a CircularListView that will be coming from corner click of screen and only half list item should be visible before scrolling. And the item in list is in Dynamic nature. And I have used these libraries from github but not getting any efficint solution from any of them. These libraries are: <a href="http://com.ramotion.circlemenu/" rel="nofollow noreferrer">1. RamotionCircleMenu -> In...

Cannot mock a kotlin sealed object method I have a sealed class that contains an object with a method I need to mock. I've tried using Powermock for this but the method does not get mocked (any calls in the test just call the original method). Here's an example of the sealed class: sealed class UseCase { operator fun invoke(parameters: P): Flowable { return execute(parameters) } object GetQuestions : UseCase() { override fun execute(params: GetQuestionsParams): Flowable { return...

Access object with an array of objects from json file kotlin My JSON file is { "events": [ { "id": "836655879846811", "name": "U.S. Girls at Baby's All Right", "type": "public", "coverPicture": "https://scontent.xx.fbcdn.net/v/t31.0-8/s720x720/24883312_1521878931228093_3223523563973203944_o.jpg?oh=9bc3e5c5d45e39c542b057b92df95243&amp;oe=5AC0353F", "profilePicture":...

Kotlin: Get method parameter values I am trying to get parameter values passed to the method I am crossing. The way I am getting it right now is using join point args. Code: @Around("@annotation(Log)") fun log(joinPoint: ProceedingJoinPoint): Any { val signature = joinPoint.signature as MethodSignature val methodName = signature.method.name val parameterTypes = signature.method.parameterTypes var paramValues = "" // TODO: make this a bit more useful logger.info("begin execution of $methodName")...

How to work with TextWatcher inside RecyclerViewAdapter I have a recyclerview and this is the item. The adapter almost works fine. The problem is when I try to add the quantity using the EditText, it doesnt work. I tried adding a TextWatcher but nothing happens. I think I'm not using it properly. This is my class inside the adapter: class ProductoViewHolder(view: View) : RecyclerView.ViewHolder(view) { var nombreProducto: TextView = view.tv_producto_seleccion...

Android - How do I keep a sticky snackbar when a new snackbar appears? I have a sticky Snackbar (Snackbar.LENGTH_INDEFINITE). In some cases, there is another temporary Snackbar (either long or short) that should appear as well. The new temporary Snackbar automatically dismisses the sticky one. I would like to keep the sticky one behind the temporary one, so that when the temporary Snackbar disappears, the sticky one is still shown. Any ideas on how to do that?

How to get status of uploading file using HttpRequest.sendStream()? I wrote a function whose uploading file to a cloud service. It works well, but I can't figure out how to check the progress of uploading file. suspend fun uploadFile(path: Path) { ... val asyncFile: AsyncFile = awaitResult { fs.open(path.toString(), OpenOptions(), it) } val methodType: HttpMethod = when (link.method.toLowerCase()) { "put" -> HttpMethod.PUT "post" -> HttpMethod.POST else -> throw UnsupportedOperationException("Method is not supported")...