Return query results to main thread without blocking I'm having trouble with Kotlin coroutines, I'm trying to query a database and return the results to the main thread, but I can't figure out how to do so without "freezing" my main thread. In this case runBlocking would be the culprit, but I'm unsure what to substitute it for. Any and all help is greatly appreciated! fun getResults() : List { val results = ArrayList() runBlocking { viewModelScope.launch(Dispatchers.IO) { openConnection() try {...

OnCompleteListener for RealTimeDatabase is not called I wonder why the onCompleteListener is not called but the data are saved to the FireBaseDatabase successfully. I just want to say: if the data are saved to FireBaseDatabase, set isSuccedded to true, but this does not happen. isSucceeded is always false. val isSaved = SaveUserToDatabase(username) if (isSaved) { Toast.makeText(this, "Success", Toast.LENGTH_SHORT).show() val intent = Intent(this, LatestTransactions::class.java) intent.flags =...

Mockk in Kotlin: Argument passed to verify is not a mock I have defined my mock as follows: private val dal = mockk { every { insert(any()) } returnsArgument 0 } Then, I'm trying to test it like this: @Test fun test() { userService.registerUser(userJohn) verify(dal).insert(check { assertEquals(it.firstName, "John") }) } This throws an exception: org.mockito.exceptions.misusing.NotAMockException: Argument passed to verify() is of type UserDal and is not a mock! Make sure you place the parenthesis correctly! I don't...

how to load admob ad in recyclerview by koltin Try to add admob in recyclerview by kotlin. Successfully load ad space between recyclerview items but fail to load ad. it keep saying that I didn't initailzed adsize and unitid although I already declared it in xml. I tried to set adsize and unitId programatically but it keep crashed saying that I cannot assign adsize and unitId twice ... Also I don't know where tocal AdRequest.Builder().build in code class PlayListAdapter(val context: Context, val playlist: ArrayList) :...

Do I need to upgrade to Java 8 for my Android Studio if I'm just writing in Kotlin? I'm working on an old project, which uses Java. It is based on Java 7. But it's now all Kotlin classes for new code. In our gradle it is still compileOptions { sourceCompatibility JavaVersion.VERSION_1_7 targetCompatibility JavaVersion.VERSION_1_7 } Just curious, is there a need to upgrade to Java 8, if moving forward I'll be writing in Kotlin? compileOptions { sourceCompatibility JavaVersion.VERSION_1_8 targetCompatibility JavaVersion.VERSION_1_8 } From <a...

FirebaseException: An internal error has occurred. [ API key expired. Please renew the API key. ] I deleted the old API keys and let Firebase create new ones but it does not work.

How to Properly Create Notification for Firestore Collection Query? So, I successfully implement notification when a Document added in a Firestore Collection, this is the code db!!.collection("voucher") .whereGreaterThan("jumlah", 0).addSnapshotListener { documentSnapshots, e -> if (e != null) { Log.d(TAG, "Error :" + e.message) } if (documentSnapshots != null) { documentSnapshots.query for (doc in documentSnapshots.documentChanges) { if (doc.type ==...

How to pass multiple data from a custom alert dialog to a fragment activity I'm just starting to build an app using kotlin(android studio) but I got stuck with this and I couldn't find a good solution for my problem at the internet. Part 1: I want to pass two different data (edit text data, one is decimal number other is text) from an alert dialog to a fragment (tab fragment) at main activity. Part 2: I want to add the 2 data from alert dialog to an item of a list view (which is inside the fragment). So everytime I entered data in the dialog view it appears as a...

Fragments are blank, but lifecycle is working properly I am working on the application, which inflates a complex UI element on socket listener. This same UI element is also inflated on a different network callback as well. This UI element includes tabLayout and viewPager (with 3 different fragments), I reuse the layout for both the use cases. this works perfectly when the network callback is triggered, but the when it is trigger via socket listener, the UI element is inflated, tabLayout is working properly, but the fragment in the viewPager are...

@CreatedDate/@LastModifiedDateset to null when merging entities I'm trying to add auditability to my entities using Spring's @CreatedDate and @LastModifiedDate. I am using Hibernate with Spring Boot. It works for inserts, but i have issues when updating entities by reusing IDs. Here is my entity class: @Entity class Serie( val name: String, val url: URL ) { @Id @GeneratedValue var id: Long = 0 @CreatedDate @Column(updatable = false, nullable = false) var createdDate: LocalDateTime? = null @LastModifiedDate @Column(nullable =...

Mapbox draw a polygon inside another polygon I want to draw a polygon inside another polygon I find how to draw a polygon in this link: and I find how to draw a hole in a polygon in this link: but I want something like this:

App dont show when implementation play-services-ads I'm facing a issue while implementing good play-services-ads, post implementation my app crashes and it doesn't appear anymore. Here is my code : apply plugin: 'com.android.application' apply plugin: 'kotlin-android' apply plugin: 'kotlin-android-extensions' android { compileSdkVersion 29 buildToolsVersion '29.0.0' defaultConfig { applicationId "dhsimple.game.blackjack" minSdkVersion 15 targetSdkVersion 29 versionCode 1...

MyAdapter with setOnClickListener in Activity does work but in Fragment does not work my Adapter with setOnClickListener in Activity does work but in my Fragment does not work. I have two Adapter with setOnClickListener,both do work in Activity on RecyclerView but None of them don't work in my Fragment's RecyclerView class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) myToolbar.title = "My Test"...

Oauth2 Node PassportJS server communicating with a Kotlin app with simple GET requests I created a NodeJs server that uses PassportJs to authenticate users with the google Api. This works perfectly in the browser where the client is redirected and given a token. The web browser does the redirect automatically as well as cookie storage. How does an app do this? The Server seems to be doing all of the work such as redirecting the client, I'm not sure how an Android app would work alongside the process. The Nodejs server sends the user back an ecrypted cookie which would allow...

How to fix 'IllegalStateException' when using custom JavaFXBuilderFactory First of all, I'm using Kotlin in my JavaFX Project. I'm trying to implement my own JavaFX Node that extends Canvas. class BrikkCanvas(width: Double, height: Double, private val rows: Int, private val cols: Int) : Canvas(width, height) I also want to be able to add BrikkCanvas directly in the FXML File like so My class has no default constructor, that's why including it in FXML is not trivial. I found out, however, that you can implement custom BuilderFactory, so I did: class...

Kotlin's Coil vs BumpTech's Glide , Square's Picasso, Facebook's Fresco A new Image loading tool/library for Android backed by Kotlin Coroutines is introduced recently named Coil. Going through docs I found out that it is best for loading images as compared to available image loading libraries in every aspect. So my question is whether I should start using Coil for my future projects or should wait for further modifications!

Custom Spring annotation not called In my Spring Boot project, I've created a custom annotation with validator extending ConstraintValidator to validate some fields in RequestBody. The annotation works fine for non-nested fields but validator is not called for nested ones. My annotation looks like: @Target(AnnotationTarget.FIELD) @Retention(AnnotationRetention.RUNTIME) @Constraint(validatedBy = [CustomValidator::class]) @Suppress("unused") @MustBeDocumented annotation class CustomValidation( val message: String =...

Not receiving any data from ViewModel I am new to ViewModels and I am having a hard time implementing one because I can hardly find any tutorial about this. I am trying to send an array of data for the Viewmodel to store so I can access it later. I think I was able to do it but my problem is fetching that data from the Viewmodel. Here is my Main Activity: val arrays = ArrayList() arrays.add("text1") arrays.add("text2") val viewmodel = ViewModelProviders.of(this)[Dbviewmodel::class.java]...

Count average value with MongoTemplate in Kotlin I use - Kotlin - Spring Boot - Spring MVC - MongoDB I need to count an average element value using MongoTemplate. An element has a property value with type Map In MongoDB ist a structure so: -elementType -value // list     -elementValue // list element When I want to count an average value, I become an exception "No property elementValue found for type Object! Traversed path: Element.value." That's logic, because the class Element has no property with that name, but a Document...

Android two-way databinding Float to EditText I am trying to use two-way databinding on a EditText. String values are working fine but I can't get it working for Float values. I have tried to use a binding adapter that I found in this answer with no luck: Android DataBinding float to TextView Then I found this Converter class on the android developers website. <a...

How to emit data to kotlin flow How can I emit new data to an existing Kotlin Flow? Currently I can only do it inside the flow block like this: val data: Flow = flow { emit(newData) } I want to do something like: fun someMethod() { data.emit(newData) } I can do it if I use Android LiveData: val data: LiveData = MutableLiveData() fun someMethod() { data.postValue(newData) // data.value = newData } or something likes it in RxJava2 with onNext event

Defining an interface as a property of an interface in kotlin and providing a concrete implemententation in interface implementation does not work I have interface A which has interface B as a field. When I do an implementation of A, let's say concreteA, and instead of providing interface B, I provide an implementation of B, the compiler throws me an error. I don't understand why, because since there is inheritance in Kotlin, I think this should work. I tried this with data classes by the way. interface B { .... } data class concreteB : B { ..... } interface A { var someField: B } data class concreteA : A { //The error...

Workmanager Worker class doWork() method not being called doWork() method of worker class never called in Android I want to sync the offline data with the server when the internet connection will be connected //Worker Manager Class class UploadWorker (context: Context, workerParameters: WorkerParameters, val authRepository: AuthRepository): Worker(context,workerParameters) { override fun doWork(): Result { Log.e("inDo", "work") GlobalScope.launch { val resource = authRepository.loginAsync("wmwdwnd@gmail.com",...

For loop stops at 100 instead of 20 I want to print the multiples of 5 while skipping multiples of 3. How do I get the for loop to stop at 20 instead of 100? fun main() { for (n in 1..20) { if (n % 3 == 0) { continue } println(n * 5) } }

New Gradle Sync is not supported due to containing Kotlin modules using an unsupported plugin version (changes ) i am trying to add pagination with recyclerview android. In one project with the same code project is working very nice and i am getting the position very well but in another project it just keeps on printing all the positions at one time. i don't know why. I thought it was error of old kotlin version so i updated my Kotlin version but then this error(New Gradle Sync is not supported due to containing Kotlin modules using an unsupported plugin version) is appearing when i importing the...

Uunresolved dependencies with 2 projects with multiple sourcesets in IntelliJ with Gradle I am experimenting with using a common Kotlin source-set and 2 specific source-sets for JS and JVM in Gradle. I know there is a kotlin-multiplatform plugin, but I wanted to try if I can make a setup like this. It works by running gradle from the command-line, but IntelliJ complains that either in the JS or in the JVM project (never both the same time) it can nog find the common classes. My directory structure is as follows: - common - src/main/kotlin/MyLibrary.kt - js -...

How can I redirect from an activity to another activity after some delays? I'm a beginner to Kotlin language. I have trouble redirection to another activity after for example 4 seconds. I know how to do it in Java but I have no idea about Kotlin. I tried android studio's converter (Java to Kotlin)

Dagger Nullable - Getting issues with Nullable while creating dagger bindings Getting [Dagger/Nullable] error while using @Inject for Drawable field. AppModule.kt @Module object AppModule { @JvmStatic @Provides fun provideRequestOptions() = RequestOptions.placeholderOf(R.drawable.white_background) .error(R.drawable.white_background) @JvmStatic @Provides fun provideGlideInstance(application: Application, requestOptions: RequestOptions) = Glide.with(application).setDefaultRequestOptions(requestOptions) @JvmStatic...

Is there any way to reuse a coroutines's channel values I wonder if there is any solution to reuse a channel's elements after they've been consumed. for example, irritating through channel 2 times. I've tried this: fun main() = runBlocking { //sampleStart val channel = Channel(2) println(channel.isEmpty) // true channel.send("foo") channel.send("bar") channel.close() println(channel.isEmpty) // false for (it in channel) println(it) // foo, bar println(channel.isEmpty) // false!!! for (it in...

Benchmark tests (JMH) with Spring Boot not working I'm trying to create some benchmark tests using JMH plugin for Kotlin. Project is build by gradle and used Spring Boot. I would like to run this test using provided task (./gradlew jmh) and I doesn't work for me. I run this code using command ./gradlew jmh Here is my build.gradle.kts: import info.solidsoft.gradle.pitest.PitestPluginExtension import org.jetbrains.kotlin.gradle.tasks.KotlinCompile buildscript { repositories { mavenCentral() } dependencies {...