Why onCreate() remembers value of local varaible? From working with all other languages functions don't remember stuff that are in them between function calls. So why is it that value of myVariable is being remembered? How many times is onCreate() actually being called? Is this function somehow being transformed into Class to allow remembering variables by storgin them as Properties? class MainActivity : ComponentActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) var myVariable =...

what is the equivalent of double colon (::) java in kotlin? orgList.getOrgMigrationMap().entrySet().stream() .filter(//some logic) .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)); Trying to get the kotlin equivalent of this code, but looks like double colon :: in kotlin means something else than java. Can someone suggest?

Permission Testing on Jetpack Compose I'm using Jetpack Compose for rendering the UI of my app. I'm currently developing some tests for a library, but I can't manage to find any proper ways to check for permissions. I'm currently using the Accompanist Permissions library to check for permissions. However, it seems like the permissions are already granted when the test starts, even though I'm currently checking for location permission, which...

Positioning or animating a view programmatically during launch phase I have a Fragment and viewBinding is available. I want to re-position a View in my ConstraintLayout. Let's say I have three views (RedView, GreenView and BlueView), RedView and GreenView are fixed in their position and BlueView should position itself on top of one of these fixed-positioned views when I want. Scenario: position BlueView on RedView when I launch the app. override fun onViewCreated(view: View, savedInstanceState: Bundle?) { binding.blue.alpha = 1f // this changes alpha...

Navigating to a composable using a deeplink with Jetpack Compose When a user enters a geo-fence in our app, we show them an offer notification about the area, which when clicked, should direct them to a specific composable screen called SingleNotification. I've followed google's codelab and their documentation but I haven't managed to make the...

How to get listitems in JSONObject? my JSON is supposed to look like this. {"zip":123, "people":[{"firstname":"Thomas", "lastname":"Tatum"}, {"firstname":"Drew", "lastname":"Uncle"}]} (I am using import org.json.JSONObject) I have a MutableList, in the List are Person (it’s a data class with firstname and lastname). But I don’t know how to get my list items in a JSONObject to fit in json (see below). val json = JSONObject( mapOf( "zip" to 123, "people" to //I don't know how to get my...

Which one should I choose between Modal drawers and modal navigation drawer in Scaffold when I use Navigation Compose? I have read the article. I know there are two ways to implement a modal navigation drawer, one is Modal drawers, and another is modal navigation drawer in Scaffold. I hope to use Navigation Compose in my project, I found a sample <a href="https://github.com/android/architecture-samples/blob/main/app/src/main/java/com/example/android/architecture/blueprints/todoapp/TodoNavGraph.kt"...

password validation no Character sequence ( kotlin android studio ) I have the task to create a password validation that has to consider some things. The only problem I have is that one of the criteria of the password validation is that the password must not contain any sequences, e.g. (12345), (abcdef), (asdfghjk). I have already searched a lot and do not know how to implement this. Can anyone help.

Expected start of the array '[', but had 'EOF' instead I'm trying to fetch data from API. My app crashes and it gives me this error: kotlinx.serialization.json.internal.JsonDecodingException: Expected start of the array '[', but had 'EOF' instead JSON input: { "generated_at": "2022-05-20T102936+00:00", "summaries": [] } I searched for a solution and found a website that corrects any errors in a json response, but unfortunately it didn't work. This is my json response (Not the whole response, just one item): {...

Ktor - Unit testing is throwing 404 I have a simple program in Ktor. It runs perfectly, but when I run the unit testing class it only throws this error: "expected: but was:" This is my unit test code: class ApplicationTest { @Test fun testRoot() = testApplication { val response = client.get("/") assertEquals(HttpStatusCode.OK, response.status) } @Test fun testStart() = testApplication { val response = client.post("/start") assertEquals(HttpStatusCode.OK, response.status) } } This is my Application.kt: const...

Kotlin DSL - type inference on returned value I'm trying to introduce the following (simplified) DSL: fun myDsl(specFn: DslSpec.() -> Unit) { val value = DslSpec().apply(specFn).fn!!() println("value is: $value") } class DslSpec { internal var fn: (() -> T)? = null fun getValue(fn: () -> T) { this.fn = fn } } fun testCase() { myDsl { getValue { "abc" } } } But it fails to infer T based just on the returned type of getValue ("Not enough information to infer type variable...

Android Kotlin Cannot serialize class I apologize in advance if I wrote my question wrong. I need the following class (AddressPointMo) to be serializable because I am sending this object using the HttpTransportSE :: call method. I have searched many reports and cannot find a solution. After executing HttpTransportSE :: call, it gets Cannot serialize: com.xxx.ksavi.android.model.AddressPointMo@f0678a47 open class AddressPointMo :Serializable, MobileTransferObject() { @PrimaryKey @NonNull @ColumnInfo var id: Long?...

kotlin clock &amp; timer I have a timer and I want to add the timer time to a clock to let the user see at what time the timer will stop. For example the timer start at 12:28pm and will finish after 12 min at 12:40pm How can I do this in Kotlin.

Jetpack Compose actually works with Classes and not Functions? When you declare @Composable Function you are actually declaring a Class Every variable that you declare inside that Function actually acts as Class Property Every Event that you declare inside that Function (like onClick) actually acts as Class Method This is why variable value is remembered between onClicks. Every click executes Class Method which increases Class Property. This can be seen in Console since we are not updating UI at this point (there is no recomposition taking place). So...

Kotlin: How to serialize a interface and ignore the class attributes interface MyInterface { fun schemaName(): String fun data(): Any } data class Object1( val name: String, val title: String, val description: String, val list: List ): MyInterface { override fun schemaName(): String = "SCHEMA_FOR_OBJECT1" override fun data(): Any = this } With this MyInterface and Object1, Kotlin serializes my Object1 into { "name": xxx, "title": xxxx, "description": xxxx, "list": [ "xxxx", "xxxx" ] } This...

Kotlin - lateinit property fragmentHomeBinding has not been initialized I am working on a kotlin application that contains fragments. I am converting an app I created using activity to fragments but I am having an issue. I get an error when running the app that the property fragmentHomeBinding has not been initialized and the app closes. Here's the fragment Home.kt class Home : Fragment() { private lateinit var fusedLocationProviderClient: FusedLocationProviderClient private lateinit var fragmentHomeBinding: FragmentHomeBinding...

How to scope a Usecase to a Feature / Activity in Koin I'm maintaining a large app (mostly) using a "one feature one activity"-architecture. Now i'd like to scope a usecase, so it lives as long as the activity, something like this: // koin module scope { viewModel { MyFeatureActivityViewModel() } viewModel { MyFeatureFragmentAViewModel(usecase = get()) } viewModel { MyFeatureFragmentBViewModel(usecase = get()) } scoped { MyFeatureUseCase() } } // fragments class FeatureAFragment: AppCompatDialogFragment(){ private val...

Recycler view updates wrong fields with data binding I have an view with this elements: When loading image into image view with glide it works fine: @BindingAdapter("loadWithGlide") fun ImageView.loadUrlWithGlide(url: String?) { val factory = DrawableCrossFadeFactory.Builder().setCrossFadeEnabled(true).build() Glide.with(this) .setDefaultRequestOptions(RequestOptions().placeholder(R.drawable.placeholder)) .load(url) .transition(DrawableTransitionOptions.withCrossFade(factory)) .into(this) } But I have an movie rating that...

New format build.gradle? I used to connect the plugin OneSignal like this How connect the plugin in new format with plugins?

What type is it in Kotlin？ when i covert the API response to object, the data would be wrong. I have no idea. My API response is Any type.Every data is correct without number data. for example D/OKHttp: result":[ 0, {"memory": { "distribution":"OpenWrt" "total":1037029376, "shared":253952, "free":946176000, "cached":27062272, "available":933396480, "buffered":2101248 }, { ......

Is there any reason to use suspend fun fn(...): Either&lt;Throwable, A&gt; over suspend fun fn(...): A? I'm mulling over something regarding suspend that Arrow's documentation explains in detail: suspend () -> A offers the same guaranties as IO<A>. So, according to the documentation, just using suspend we are converting our impure functions into pure functions: Impure fun log(message: String): Unit = println(message) fun main(): Unit { // The edge of our world log("Hey!") } Pure suspend fun log(message: String): Unit = println(message) fun main(): Unit = runBlocking { log("Hey!") }...

I'm trying to pass an ArrayList&lt;CustomObject&gt; into a fragment activity&gt; in Kotlin. How would I do that? I assume it should look something like this? Fragment1.kt import android.os.Bundle import androidx.fragment.app.Fragment import android.view.LayoutInflater import android.view.View import android.view.ViewGroup private const val ARG_PARAM1 = "param1" class Fragment1 : Fragment() { private var param1: ArrayList? = null override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) arguments?.let { param1 = it.get(ARG_PARAM1) as...

android kotlin list of dates to range I have a list of dates not in a particular order. I want to create a list of date ranges from the given list. e.g: val stringList = ["22-03-2022","23-03-2022","24-03-2022", "10-04-2022","11-04-2022","12-04-2022","01-05-2022","02-05-2022"] desired o/p: val rangeList = [("fromDate":"22-03-2022","endDate":"24-03-2022"),("fromDate":"10-04-2022","endDate":"12-04-2022"),("fromDate":"01-05-2022","endDate":"02-05-2022")]

Why is remember variable reinitialized during recomposition when I am using remember Keyword? Why is remember variable reinitialized during recomposition when I am using remember Keyword? MyComposable is depended on state Variable which is increased when I press Button. Because of that MyComposable become reinitialized. But why is it that during recomposition myProperty is reset when I am using remember Keyword? Is it because remember works only for variable which caused recomposition? MainActivity.java //====================================================================== // MAIN...

Calculate the total price from recycler view Excuse me, so this chance I'd like to calculate the final total price that calculates from the sum of total price (this calculation is from quantity per item multiplied by item price) for each item in the cart. Can anybody help me to solve this? thank you here is the cartadapter.kt class CartAdapter( private val listItems: ArrayList ) : RecyclerView.Adapter() { private lateinit var database: CartRoomDatabase private lateinit var dao: CartDao override fun onCreateViewHolder(parent:...

RecyclerView adding extra space between items I've a grid of items that change their position every few seconds based on the input from the server. Upon every change, I update the adapter and the items move around in the grid. I want to add space on top & bottom of an item if they're on second line or later lines. The items in first line of the grid have space only on the bottom of the item. The problem I'm running into is upon every data change in the grid that results in item moving around Eg. Item that's on the second line is now the...

what is difference between in creating and getting in kotlin Hey I am working in Kotlin Multiplatform. I see in gradle file I have kotlin block inside that I have getting/creating. Can someone explain me what is diifference between creating and getting with example? Getting val commonMain by getting val androidMain by getting val iosMain by getting Creating val commonMain by creating val androidMain by creating val iosMain by creating

Cursor not moving after adding click tracking on endDrawable I add onTouch tracking for EditText. Here my code: editPassword.setOnTouchListener( View.OnTouchListener { view, event -> when (event.action) { MotionEvent.ACTION_DOWN -> { if (event.rawX >= editPassword.right - resources.getDimension(R.dimen._48pxh)) { editPassword.setTransformationMethod ( if (passwordVisible) null else PasswordTransformationMethod());...

Vaadin 23 issue with production mode using spring boot with gradle task bootJar I'm trying to create an executable jar file. For this project I am using gradle. I am building executable jar file using gradle task "bootJar". Unfortunately after starting my jar file like this: java -jar -Dvaadin.productionMode=true /Users/fluento/IdeaProjects/respinewsbackend/build/libs/respinews.jar or: java -jar /Users/fluento/IdeaProjects/respinewsbackend/build/libs/respinews.jar this error occurs in console: Caused by: java.lang.IllegalStateException: Running project in development...

Find the closest stack total where number of n values should be the same in all stack Lets say I have a array of random numbers {7,5,4,8,12,10,4,78,12,32,43,12} Two values which can be changed s and n (s > 1)(n > 1) s = numbers of stacks n = fix number that each of these stacks can hold (random numbers will always be dividable by n and s so that each stack will always have the same numbers of values) I want to find closest total of all the s stacks when all the n will be added. And I Want to achieve it using Kotlin/java but you can give example in any language or you can just...