Is it a bad practice seeking a data in list by index multiple times? I have like below code, override fun onBindViewHolder(holder: ViewHolder, position: Int) { val view = holder.view view.apply { name.text = list[position].name age.text = list[position].age address1.text = list[position].address1 address2.text = list[position].address2 zip_code.text = list[position].zip_code } } it's seeking the data multiple times to get each property, like name, age, address1.. And I'm wondered is it better assign the...

Why immutable properties doesn't work with Room entities in Android I have been exploring Room database object mapping library and I figured something weird. An entity data model cannot have val properties, as this answer suggests. But I checked out <a href="https://github.com/googlesamples/android-architecture-components/tree/master/BasicRxJavaSampleKotlin" rel="nofollow noreferrer">google's...

How to pass a string to a var without escape symbol in Kotlin? I hope to pass the string {"name":"My Settings 1"} to a var aa I have to write it using the code var aa=" {\"name\":\"My Settings 1\"} " Is there a simple way in Kotlin when I use Android Studio 3.0 ? I know is good for XML content

Kotlin coroutines in Android: Why use bg() from Anko instead of async()? I started using Kotlin coroutines on Android today and I noticed that Anko has its own set of helper methods for them. I understand why asReference() exists, but I can't figure out why bg() does, given that the core coroutines lib already has async(). The bg() code is quite simple and it uses async() inside: @PublishedApi internal var POOL = newFixedThreadPoolContext(2 * Runtime.getRuntime().availableProcessors(), "bg") inline fun bg(crossinline block: () -> T): Deferred = async(POOL) {...

How to set FloatingActionButton border width with Anko I've just switched from Java to Kotlin and I'm using Anko for building layouts. and this is my layout : relativeLayout { floatingActionButton { imageSource = R.drawable.kotlin_is_amazing }.lparams { width = wrapContent height = wrapContent } } now the question is how to set app:borderWidth with Anko ?

Obtaining the value from Flux&amp;lt;&amp;gt; in Polymer based client app I have created a simple Spring boot 2.0 based application which has a controller that produces MediaType.APPLICATION_STREAM_JSON_VALUE. Here is the code for controller method: @GetMapping(path = arrayOf("/all"), produces = arrayOf(MediaType.APPLICATION_STREAM_JSON_VALUE)) fun getAll(): Flux = registry.getAllPersons() .delayElements(Duration.ofSeconds(1L)) When this REST API is called directly from the browser or Postman, it produces expected result ie. each Person object is...

List of objects that implements interface With interface Anint { fun doStuff() } class AClass : Anint { override fun doStuff() = print("hello") } class AnintManager { //val l = listOf fun manage() { //for each Anint, doStuff() } } fun main(args: Array) { val a = AClass() val b = AClass() AnintManager().manage() } How can I do so that every time I instanciate a new object that implement "Anint", that object gets added to list in the "AnintManager"? It'll be cool if the code for achieving this is...

PlaceAutoCompleteFragment closing issue I facing sudden closing of PlaceAutocompleteFragment. I am getting this error Status{statusCode=ERROR, resolution=null} My xml layout MyKotlin code override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main3) val autocompleteFragment = fragmentManager.findFragmentById(R.id.place_autocomplete_fragment) as PlaceAutocompleteFragment val typeFilter = AutocompleteFilter.Builder()...

Can you use object that is synchronized as a lock Is this code ok, or should I create a separate lock object? var foo = false fun bar() { synchronized(foo) { foo = !foo } }

Is there a way to change my method to Observable stream which will be a chain of modifiers? Originally i have a function like this: private fun rxSaveEvents( events: List, locationUpdatesAboutToStop: Boolean): Boolean { synchronized(mEventsMonitor) { if (events.isNotEmpty()) { val locationEvents = LocationEvents() segregateLocationEvents(events, locationEvents) scoreReadings(locationEvents) sendLocationEventsInternal(locationEvents, locationUpdatesAboutToStop) Completable.fromCallable {...

Android - Add UNDO SnackBar to Swipe to delete I have successfully implemented the swipe to delete action within my recyclerView. The list I inflate the recyclerView with is locally stored and isn't in any database. What I tried to do is to save the element to a temporary variable and if the user presses the undo button, I would restore it. This is my code: override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) { val position = viewHolder.adapterPosition //get position which is swipe...

Updating the Recycler View and Creating Parcelables for screen rotation (What's the best course of action here?) I've been trying to learn Kotlin slowly for two months. I made a Reddit App in Kotlin to display thumbnails in a Recycler View Grid Layout My Repository In the apiCall method in the <a href="https://github.com/ronaldosanches/RedditJustShowMeImages/blob/master/app/src/main/java/com/ronaldosanches/redditjustshowmeimages/MainActivity.kt" rel="nofollow noreferrer"...

Kotlin collections map causing a 'Type Checking Has Run Into A Recursive In Kotlin' error I have 2 classes lets call them A and B, I also have a function that converts an instance of A to an instance of B. My code that is causing issues is basically: fun fromAtoB(a: A) = B (fb1 = a.fa1, fb2 = a.fa2, fb3 = a.fa3) val listOfA: List<A> = ... val listOfB: listOfA.map { fromAtoB(it) } This won't build due to the line: fromAtoB(it) With the error: Due to the error Type checking has run into a recursive problem. Easiest workaround: specify types of your declarations...

How do get kotlintest to work with Spring? I'm trying to use kotlintest along with Spring (not Spring Boot, just the standard spring-test). I'm finding it very difficult to do. Any pointers as to what I am doing wrong? I am somewhat of a Kotlin newbie as well so I could very well not be doing something correctly. This is what I've tried so far: import io.kotlintest.matchers.shouldBe import io.kotlintest.specs.BehaviorSpec import org.junit.ClassRule import org.junit.Rule import org.springframework.context.annotation.Bean import...

how to convert json array to json object I am using Retrofit 2 in my project my app get data from tow APIs api1 and api2 api1 :- [{"id":"29867","category_id":"31","author":"admins", "title":"hi","abstract":"","image_name":"","created":"11","body":"hi"}, {"id":"29866","category_id":"14","author":"admins", "title":"hi2","abstract":"","image_name":"img.png","created":"2017-11-16 160200","body":"heloo"}] and api2 :- [{"obj":"29867","category_id":"31","obj2":"admins",...

Set value of a field without calling set method - Kotlin I've been using Kotlin to develop some apps in Android and what i want to do currently is to set a field value inside the defining class without calling the setter method. Here is the code inside my class: var projectList: List? = null set(value) { saveProjects(value as ArrayList) field = value } //GO to the database and retrieve list of projects fun loadProjects(callback: Project.OnProjectsLoadedListener) {...

super.onCreateAnimation always returns null Im trying to use the android.support.v4.app.Fragment's onCreateAnimation(int transit, boolean enter, int nextAnim) method. When I override this method in a subclass fragment and call super.onCreateAnimation(transit, enter, nextAnim) I always get a null pointer exception because it returns null. This is the code I have in my fragment: override fun onCreateAnimation(transit: Int, enter: Boolean, nextAnim: Int): Animation { return super.onCreateAnimation(transit, enter, nextAnim) } If...

Spring Kotlin @Autowired with @Qualifier using wrong Type? I am using Kotlin with Spring Boot. I have multiple XML files that have my queries external using Spring util namespace. When I try to inject it though it is telling me it expects java.lang.String??? *************************** APPLICATION FAILED TO START *************************** Description: Field queries in com.xxxx.xxxx.xxxx.brand.JdbcBrandService required a bean of type 'java.lang.String' that could not be found. Action: Consider defining a bean of type 'java.lang.String' in your...

with c++ knowledge can i learn kotlin language/script ?? [on hold] I am planning to learn android programming, I’ve good knowledge on c++, recently I heard about “KOTLIN” by which we can develop android application, for me is there any pre-requisites are required to learn KOTLIN??

Set custom notification sound in Kotlin? Id like to have a special tone go off to tell the user the joke of the day has been delivered. Everything works, except my custom tone, drumroll.mp3 won't play. Here's the code that builds out my notification: var builder: NotificationCompat.Builder? val tone = Uri.parse("android.resource://" + context.packageName + "/" + "R.raw.drumroll") builder = builder .setSmallIcon(R.mipmap.ic_launcher_round) .setColor(Color.BLUE) .setContentTitle("Content Title") .setTicker("TICKER Text")...

Can't build project with Android Studio 3.0 + DataBinding + Kotlin I have a huge project with databinding, kotlin, dagger. I spent a few days trying to build it using several stackoverflow's solutions and decided to ask it personally. I assume some of third party libraries uses databinding too because adding this line doesn't help. kapt 'com.android.databindingcompiler3.0.0' Android Studio says: 'androidProcessor' dependencies won't be recognized as kapt annotation processors. Please change the configuration name to 'kapt' for these artifacts:...

Spring Injecting util:map in Kotlin with type safety I have the several bean definitions in XML to store my SQL externally. I want to inject them in Kotlin as Map however the only way I've been able to make it work so far it injecting it as Map. Is there a way to ensure type safety here. Injecting it as Map feels ghetto. When I try Map or even Map I get not qualifying beans found... Example XML Injection into service @Service open class JdbcBrandService...

Using Replace function in KOTLIN I am try to replace the cyrlic characters by using Latin The following codes works val kztext83: String = kztext82.replace('ə','ä') but the actual translation is not ä , it is a' Since a' is two character i am getting errror for val kztext83: String = kztext82.replace('ə','a'') Error is - too many character in character literal ? I tried many ways including creating string , not fixing the issues

Highlight multiple items in android list view when selected I have a listview with all the user's contacts and their relevant phone numbers. I want them to be able to select multiple cells/rows and then the list must highlight the select contacts so that the user does not lose there state. I have a custom adapter setup that looks as follows. public class ContactsListAdapter extends BaseAdapter { private static final String TAG = "ContactsListAdapter"; /*********** Declare Used Variables *********/ private Activity activity; private ArrayList...

How can I integrate the functionality of this c++ code into my android application? I have written a very small program in C++ using the libtins packet crafting library. I'd like to be able to use this functionality in my android application (written using kotlin), but instead of printing the data I would like to store it in an object. I looked at possibly using the JNI to accomplish this but I am unfamiliar with it and it seems rather complex. Any help would be greatly appreciated! #include #include using namespace std; using namespace Tins; bool callback(const PDU...

The easiest way to get hotswap ability while using kotlin-to-js transpiler? What is a easiest way / tools / technologies to get hotswap ability, while coding HTML (kotlinx-html-builder) and pure javascript (kotlin-to-js) using kotlin & gradle & IDEA ? Not very desirable to use create-react-kotlin-app (since i'm coding pure simple js).

Expected single matching bean but found 3: objectMapper,halObjectMapper,_halObjectMapper in junitTest I'm having a problem with my testing. I'm using java spring and trying to run junit test to check if my server is alive. This the test I'm trying: @RunWith(SpringJUnit4ClassRunner::class) @ContextConfiguration(classes = arrayOf(ServiceContext:class,DatabaseContext:class)) @Transactional open class newtest : AbstractTestController(){ @Test fun echoTest() { var x=0 mockMvc.perform(get("/echo").contentType(MediaType.APPLICATION_JSON)).andExpect(status().isOk) } } This is...

RecyclerView - Correctly implement SnackBar UNDO deletion (Kotlin) I have successfully implemented the swipe to delete an item from the recyclerView. When an Item is deleted I want top show a SnackBar with a button that's let's you add back the item if you deleted unintentionally. I chose to store the swiped item in a variable and delete it. Then, if the user presses the undo button, it will be added back to the position it used to be. This is how I did it: override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {...

Android Retrofit Get Query encoded I'm trying to use simple get request with retrofit, but i've problem with parameters name, characters "[" and "]" are not encoded. @Headers("Accept: application/vnd.api+json") @GET("v2/point_of_sales/{point_of_sales}/books") fun retrievesBooks(@Path("point_of_sales", encoded = true) pointOfSales: String, @Query("include", encoded = true) include: String, @Query("fields[category]", encoded = true) fieldsCategory: String,...

Kotlin data class copy method not deep copying all members Could someone explain how exactly the copy method for Kotlin data classes work? It seems like for some members, a (deep) copy is not actually created and the references are still to the original. fun test() { val bar = Bar(0) val foo = Foo(5, bar, mutableListOf(1, 2, 3)) println("foo : $foo") val barCopy = bar.copy() val fooCopy = foo.copy() foo.a = 10 bar.x = 2 foo.list.add(4) println("foo : $foo") println("fooCopy: $fooCopy")...