I have this POST request to an api but it crashes. Im not sure on how to have the function run in the background instead of the main thread I tired to use Async But im not sure on how to use it. All I know is that The function has to run on the background Thread button.setOnClickListener { run() } } } fun run() { val client = OkHttpClient() // this sets up the header and body settings val mediaType = MediaType.parse("application/json") val body = RequestBody.create( mediaType, "{\r\n \"dateTime\": \"2019-07-01T000000-07:00\",\r\n...

How to fix version incompatability in gradle.app in the gradle file i cant compile the project due incompatability with the line implementation 'com.android.supportappcompat v727.0.0' to fix this isssue, i tried to modify it to v7:28.0.0..but it did not fix the issue please let me know how to solve it code: apply plugin: 'kotlin-android' apply plugin: 'kotlin-android-extensions' android { compileSdkVersion 27 defaultConfig { applicationId "com.example.kotlindynmaicfragment_v1" minSdkVersion 19 targetSdkVersion 27...

How to convert Java lambda based on functional interface to Kotlin one? I have the next java functional interface @FunctionalInterface public interface FragmentHandler { void onFragment(DirectBuffer buffer, int offset, int length, Header header); } I have a very simple interface implementation public static FragmentHandler printStringMessage(int streamId) { return (buffer, offset, length, header) -> { byte[] data = new byte[length]; buffer.getBytes(offset, data); System.out.println(String.format("Message to stream %d from...

Getting null instance from dagger 2 I am developing an app in which I have defined multiple layers and using dagger2 for instance management etc. I have managers, services and views. I am trying to set manager in a @Module like: @Module class ManagerModule { @Provides @Singleton fun provideDatabaseContext(userManager: UserManager) : DatabaseContext { var databaseContext : DatabaseContext = DatabaseContext(); databaseContext.setUserManager(userManager) return databaseContext } @Provides @Singleton fun...

RecyclerView in Fragment crashes when navigating to another Fragment I've been following examples on the web to create a RecyclerView. The only thing I made different is to put the RecyclerView in a Fragment instead of having it in the MainActivity. The RecyclerView displays nicely with the data. But when I navigate to another Fragment the App crashes with an Exception relating to RecyclerView: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.support.v7.widget.RecyclerView$ViewHolder.shouldIgnore()' on a null object reference...

Access build.gradle version property in application code I have a basic build.gradle file like so where I define my apps group and version properties as outlined in Build Script Basics: build.gradle ... group 'my-group' version '0.1.0' ... How can I access the version property in my application code? Currently, I am just hardcoding the value a second time. Would be nice if I can grab it from the build.gradle file app.kt object...

How can i get DEVICE_ADMIN permissions on Android TV? I work for my simple app. It must lock the device screen. The application requests DEVICE_ADMIN rights to lock the screen, send to sleep. I work in Android Studio. On the smartphone emulator Pixel it works. But on Android TV does not work. White screen and all. Permissions are not requested at start app. How can I get rights to Android TV? (as I described in the Manifesto). Maybe I did something wrong? I show you my manifest. Some code to show? Thanks in advance Manifest:

How to do url encoding for query parameters in Kotlin I am new to Kotlin & I am trying to url encode my url which has query parameters. private const val HREF = "date?July 8, 2019" private const val ENCODED_HREF = print(URLEncoder.encode(HREF, "utf-8")) private const val URL = "www.example.com/"+"$ENCODED_HREF" Error: Const 'val' has type 'Unit'. Only primitives and Strings are allowed for private const val ENCODED_HREF

Is the addSource onChange callback of Mediator LiveData executed on the main thread by default? From the documentation: addSource (LiveData source, Observer onChanged) Starts to listen the given source LiveData, onChanged observer will be called when source value was changed. onChanged callback will be called only when this MediatorLiveData is active. If the given LiveData is already added as a source but with a different Observer, IllegalArgumentException will be thrown. From the source code, it says that the addSource function is always...

How to make the viewmodel observe the repository without lifecycle object I'm building an android application with MVVM design and I have multiple layers(view, ViewModel, repository and dataSource both local and remote). I want that my repository object will observe the dataSources, do all of his logic for how and when storing cache, map the data to the correct form for the above layer and only then notify the view model about the new data. Similar to that I want the ViewModel to observe the repository for new data arrival, then doing all the business logic and...

Installing Kotlin & Eclipse from command line I have installed Java & Eclipse with these commands: sudo apt install default-jre sudo snap install --classic eclipse Kotlin Plugin for Eclipse says 'to drag this button into a running Eclipse window:' How can I use the command line instead?

Mapbox navigation getRoute() is successful, but doesn't show route I'm following Mapbox's Route Generation tutorial for android and I used the exact same code as the documentation: val origin = Point.fromLngLat(124.132465, -35.752721) val destination = Point.fromLngLat(125.132465, -36.752721) NavigationRoute.builder(context) .accessToken(getString(R.string.mapbox_access_token)) .origin(origin) .destination(destination) .build()...

text formating does not accept complex objects I want to form this text string which is having multiple quotes like this {"TO":"getWatsonMessage","JR":{"Text":"Hi","userID":"4","Context":{"userprofile":[{"sex":"male","date of birth":"2010-01-03","image":"","clinics":[1],"primary_provider":[{"clinic":1,"patient":1,"providers":1}],"role":"patient","last name":"John","address":"300 east main st. San Jose, Ca 95014","first...

How to find and debug where the actual code line Java Error: Fatal Exception: java.lang.IndexOutOfBoundsException: I have following error coming up in my crashletics log, I know this error is related to array index is out of bound and i know how i can fix it, However, my question is how in the world I find where this happens from this below log, Because all the hints in the logs are GENERIC and code-base pretty large that it's hard to check everywhere with breakpoints, And since happens very rarely on some race condition, Can anyone can give me a clue on the right direction on how to find out ? Fatal...

Is there a way to perform a Firestore query that would work like `whereEqualToAny(field, list/array)`? I have a requirement where in I need to query all documents with a field that can match any of the values inside a long list of strings. Specifically this is for a newsfeed and post like feature. So each user will have a posts, followers, and following collection. The newsfeed screen will then have a query of something like: firestore.collectionGroup(“posts”) .whereEuqalToAny("postBy", [my.followers]) .orderBy(“dateAdded”, SortOptions.DESC) .limit(10) .get() This query would...

Kotlin - path in Activity when passed to Fragment shows up as null and then changes value I have a situation in which I am trying to pass the path from an Activity to a Fragment. Below is a snippet of my MainActivity.kt file: MainActivity.kt override fun onCreate(savedInstanceState: Bundle?) { val myDir = File(getApplicationContext()?.getExternalFilesDir(null)?.toString() + "/") // below line displays the path Toast.makeText(applicationContext, "MainActivity: " + myDir.toString(), Toast.LENGTH_LONG).show() super.onCreate(savedInstanceState)...

How to update particular columns of mutliple rows with different values using Room? Say I have a table 'cities_with_customers' with columns id | city | customers ---+------------+---------- 1 | London | 5 2 | Bristol | 6 3 | Birmingham | 7 and a map with no ids val map: mapOf("London" to 20, "Birmingham" to 5) // No ids! Now I could go on and do this @Query("UPDATE cities_with_customers SET customers = :v WHERE city LIKE :k") } fun update(k: String, v: Int) and for((k, v) in map) dao.update(k,v) But is there a way to optimise it to a single...

Manifest merger failed : Referenced navigation file not found I am trying to add a nested graph to my Navigation XML file. The main graph is in the app module and the nested graph is in a dependent library module. I am adding the subgraph with tag. When I do it my build fails with manifest merger error. I have the main graph referenced in app's Manifest as tag to support deep linking. I do search in the project but I can't find any references to my subgraph but in the include tag. Manifest merger failed : Referenced navigation file with...

How to open request in default browser for onCreateWindow in Android? I am working on Android/Kotlin WebView. I have set, webView.webViewClient = MyWebViewClient(mContext) webView.webChromeClient = MyWebViewChromeClient(mContext) val settings = webView.settings settings.userAgentString = "App Agent" settings.javaScriptCanOpenWindowsAutomatically = true settings.setSupportMultipleWindows(true) Now, when a new window request comes from web app,currently it's opening the new window with apps webView like, class MyWebViewChromeClient(private val...

How to fix 'JAVA_LETTER_OR_DIGIT' in Android Studio I'm trying to build a project, but when tried to do that, I got the following on console: JAVA_LETTER_OR_DIGIT this is the stack trace: org.gradle.api.ProjectConfigurationException: A problem occurred configuring project ':app'. at org.gradle.configuration.project.LifecycleProjectEvaluator.addConfigurationFailure(LifecycleProjectEvaluator.java:94) at org.gradle.configuration.project.LifecycleProjectEvaluator.notifyAfterEvaluate(LifecycleProjectEvaluator.java:89) at...

Convert android studio environment from kotlin to java I'm still beginner in android studio ,and I'm asking if I can change the whole android studio code files from kotlin to java ?!

Static BroadcastReceiver not working ANDROID I'm trying to create a static broadcast receiver, but it is not working. AndroidManifest ScreenReceiver.java package com.example.broadcastreceivertry; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.util.Log; public class ScreenReceiver...

Terminating the readLine() function when encountered with a whitespace So, I have started using Kotlin to solve some basic problems at websites like CodeChef and Codeforces where I got caught up on a problem. The question requires us to input 2 integer variables, say x and y, followed by y-spaced integers, say m1, m2, m3 and so on till mY. But the way it is being input is as shown: 4 3 3 2 3 And my Kotlin code for input is this: fun main(args: Array) { val n = readLine()!!.toInt() val m = readLine()!!.toInt() var a:Int for(i in 1..m) {...

Any advise about the pie chart library for android? I have no idea which library is suitable for my project. I'm using kotlin to develop the mobile application and i just want only pie chart to display the added information. Any advise?

Android: CalendarProvider events not created and sometimes disappears after created(in few devices) I am creating calendat event programatically(Android platform). Following is my piece of code: Here User has right to select plan date(planDate.value), start time(planStartTime.value), end time(planEndTime.value) and enter plan name(planName.value) private fun createCalendarEvent(context: Context) { val startDateObj = SimpleDateFormat(simpleDateFormateMM, Locale.US).parse("${planDate.value} ${planStartTime.value}") // Here I am fetching data selected by user val endDateObj =...

Menu item inside NavigationView onClick is triggered only on double click I've created menu for NavigationView by adding ListView inside my NavigationView. Then I made custom ArrayAdapter where each menu item is added. Each menu item has custom xml layout attached to it. Root of this layout is used by onClickListener triggering function passed to menu item class as parameter. Everything works perfectly, but as I click on item, it will not trigger this function, only as I double click. Why is this behavior happening? Code: This is class for menu item (multiple...

How to equals Kotlin & Java BasicTypes I want to getTypeByClass() in my Android Application. This function is exchange the class to string. public fun getTypeByClass(type: Class): String { return if (type == String::class.java) { "TEXT" } else if (type == Long::class.java) { "INTEGER" } else { "NULL" } } System.err.println(getTypeByClass(Long.class)); The output is NULL，but i need INTEGER.

Android SecurityException: uid 10178 cannot explicitly add accounts I receive the error message java.lang.SecurityException: uid 10178 cannot explicitly add accounts of type: net.roughdesign.swms even with the most basic example I could create. It consists of: Account configuration account type in strings.xml net.roughdesign.swms authenticator.xml SwmsAccountAuthenticator.kt class SwmsAccountAuthenticator(val context: Context) : AbstractAccountAuthenticator(context) { override fun addAccount( response:...

RxJava stream repeats twice for each record retrieved from database I have an RxJava stream that goes through all the records in a table, one at a time, sends an email for each recipient in each record and stores the status of whether the sending was successful or not. This loop repeats itself until all recipients have been read from the database and messages sent to them. The problem I am having is that code from the start of the stream (starting at getMessagesToSend) up to the storeMessageSent gets called twice for each recipient (except for the first...

Why is there a separation between the iterator operator and Iterable interface in Kotlin? I am very confused about the separation between operator fun iterator() and the Iterable interface. The only function that Iterable requires is operator fun iterator(), which is already built into the language. I can't figure out why there would be any case that you would implement operator fun iterator() but not the Iterable interface as well. This begs the question: why are you able to make something iterable without implementing the corresponding interface? It seems like it would be a...