anko sqlite database migration Does anyone know how database migration work with Anko Sqlite? I see this code but there is little documentation override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) { // Here you can upgrade tables, as usual db.dropTable("User", true) } I don't want to drop the table User when upgrading to a new version of the database, I want to keep the customer's data.

Is it fine if I put a button onClickHandler which gonna show a alert in view model? The View model it self has no knowledge of the view. class AuthViewModel( private val userPreference: UserPreference, private val deviceId: DeviceId, private val authHelper: BaseAuth ) : BaseViewModel() { } But inside it, I have a event handler for a button which will show a dialog, no matter which view it gonna binds to. It always gonna show a alert after pressing. So I add some code like the following: fun letMeJoinHandler(view: View) { with(view.context) {...

How to make indeterminateProgressDialog in Anko non cancelable? How to make indeterminateProgressDialog non cancellable? There is a isCancelable property for alert, but seems not the case for indeterminateProgressDialog, how to solve it?

Refresh View Whilst Function Still Executes I am trying to play the simplest "animation", by making a TextView say "foo", wait a second, then say "bar". The problem is that instead of seeing the label nicely shifting, it freezes for the whole second and then just says the last requested text. val label = findViewById(R.id.textView) val button = findViewById(R.id.button) button.setOnClickListener { label.text = "foo" // some "label.update()" has to be called here Thread.sleep(1000) label.text = "bar" } In C# I would...

ndroid.view.InflateException: Binary XML file line #11: Error inflating class de.ehsun.coloredtimebar.TimelineView hi i'm working on a app in which user can reserve a seat. user has to choose a time range for his booking. i wanted a time range picker in which i can customize the time whereas user can only choose time from 07:00 to 19:00. i found library called colored-time-selector https://github.com/ehsunshine/colored-time-selector this library has everything what i was looking for. but i'm facing below error...

Add relative location RelativeLayout.BELOW I've the below code, in which I construct a "card" and adding to it both Switch and button, I need the button to be exactly under the switch, how to make it! val swithy = Switch(this).apply { text = "active" isChecked = true id = View.generateViewId() } val mcard = CardView(this).apply { background = getDrawable(R.drawable.card_background) radius = 12F setContentPadding(25, 25, 25, 25) setCardBackgroundColor(Color.LTGRAY) cardElevation = 8F...

How can I extension Java class with Kotlin to use like static fun? public class TestA { public static a() {} } fun TesstA.b(){} How can I extension Java class with Kotlin to use like static fun ? just like TesstA.b() to use this fun

Type mismatch error for an interface I am creating an android application with kotlin (just learning). I need to use a callback interface, the interface documentation is here. This interface has two arguments, first is String type and second is std_msgs.String type (i have supplied the right arguments), but it is not working. I am receiving an type mis-match error as...

Kotlin Generic List Parsing I was looking other questions but this one is using a different method. I’m using MVVM in my Android app. Actually this is the way that I’m getting data from my server: Inject dataManager into viewModel. viewModel calls dataManager->fetchUsers fetchUsers make request to server and return an Observable of Several which in this case should be Several but it’s generic. viewModel subscribe to this request and expect a Several. At this point everything works besides Several doesn’t...

How to test whether the activity has not been routed with Robolectric? I have an activity which is as simple as this: class HomeActivity : BaseActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_home) if (!this.userPreference.memberRegistered) { goToActivity(AuthActivity::class.java) } } } So if the user is registered, it will stay at HomeActivity, otherwise it will route to AuthActivity. userPreference is a wrapper around...

How to access Javascript module with Duktape in Android I am successfully parsing and evaluating a javascript file with Duktape in my Android application using Kotlin. val file_name = "lib.js" val js_string = application.assets.open(file_name).bufferedReader().use { it.readText() } val duktape = Duktape.create() try { Log.d("Greeting", duktape.evaluate("'hello world'.toUpperCase();").toString()) duktape.evaluate(js_string) } finally { duktape.close() } The javascript file was created with Browserify, so it is one single file with...

How to mark not to call super class' implementation when overriding? Suppose a Library's method takes a callback handler Handler, but for handling the result, the same logic is used over and over again. So, I created a class SimpleHandler that has the logic. The users that use that class are suppose to override its methods onSuccess onFail, if necessary. But if the handling is not necessary for the specific case, the user may not override them, and the SimpleHandler's default handler will be used. The problem is that when I auto-complete the methods, the IDE...

Kotlin: Documentation for property setter I am writing a Kotlin library. In one of the classes, I have the following: class SessionWrapper { /** * The time in milliseconds after which the session will expire. */ var expiryTime = DEFAULT_EXPIRY_TIME get() { mainThreadCheck() return field } set(value) { mainThreadCheck() field = value updateExpiry(value)

Android Studio NullpointerException using Intent + Bundle I'm trying to pass a text field from an activity to a fragment, using this code: EditText textPlayer1; public void goToSinglePlayer() { Intent intent = new Intent(this, ActivitySinglePlayer.class); String player1Name = textPlayer1.getText().toString(); Bundle bundle = new Bundle(); bundle.putString(player1Name, "player1Name"); intent.putExtras(bundle); startActivity(intent); } I want a player to enter the text, and then pass the name to the fragment. When I recieve...

Retreiving data from bundle in Kotlin throws android.os.BadParcelableException: ClassNotFoundException when unmarshalling I'm using org.jetbrains.kotlin.android.extensions to parcel data. This is my data class @Parcelize data class MusicTrack( val id: Long, val title: String, val albumId: String, val artist: String, val duration: String, val trackArt: String = "", val fileUri: Uri) : Parcelable This is how I send my data across to my Service override fun playTrack(position: Int, musicList: ArrayList) { info { musicList } val bundle = bundleOf(...

Which android platform should I choose? [on hold] Hello dear friends. I have the idea of implementing an android in my mind. I will do something like a knowledge game. ( trivia crack) is it better for me to choose which platform for this? -android studio (a very large platform. I used it to make more Android apps. I do not know how much you're gonna force me. Also, I do not have much knowledge in Java language) -xamarin(I am better at c # applications but the number of resources in turkish is low) -unity(in-app transitions are easy, but the...

Kotlin: Generic Iterator over Enum: how to declare type variables My (non compiling) code for a generic iterator over enumerations is as follows: class EnumIterator: Iterator { private var cursor = 0 override fun hasNext(): Boolean = cursor < enumValues().size - 1 override fun next(): T = enumValues()[cursor++] } The IntelliJ IDE marks the T in both enumValues< T > red: "Cannot use 'T' as reified type parameter. Use a class instead." How to declare the type parameters to get rid of the error?

Android unable to build project after updating kotlin runtime to 1.2.31 After updating kotlin runtime to 1.2.31 from 1.2.30 this morning, I was unable to build the project. Below are the build.gradle in project level. What I did is only changing the line of the ext.kotlin_version to '1.2.31'. The android studio also prompted me to upgrade the gradle plugin to 4.4, which i did but I don't know if it's related to this issue. buildscript { ext.kotlin_version = '1.2.31' ext.anko_version='0.10.4' ext.rxjava_version='2.1.12'...

Mixing Kotlin and Java code I want to use a Kotlin Android library (FotoApparat) in a Java Android project. In a Kotlin code base the whenAvailble function gets a kotlin callback as a param, which will be called when the async operation is done. val photoResult = fotoapparat.takePicture() // Asynchronously saves photo to file photoResult.saveToFile(someFile) // Asynchronously converts photo to bitmap and returns the result on the main thread photoResult .toBitmap() .whenAvailable { bitmapPhoto ->...

Fuel Expected Begin Array but was Begin Object I'm new to Kotlin and I'm still learning how to get an object respose but I'm having the following exception: com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 1 column 2 path $ Here's the Json Result: {"Success":"1","Message":"True","Items":[{"Id":3,"Name":"AndroidVersion","Value":"1"},{"Id":4,"Name":"IOSVersion","Value":"1.0"},{"Id":5,"Name":"AndroidForceUpdate","Value":"true"}]} Here's the model class data class...

How to create a convex path in android I need to create a convex path in android (in order to feed it into a ViewOutlineProvider for casting shadows when a specific view is getting its elevation to be more than 0) I only use path.quadTo(...) which only adds control points, so I was thinking this whole thing will be 1 contour and convex. By my app crashes when using the calculated path, as it causes java.lang.IllegalArgumentException: path must be convex. In addition, the println() is printing "false" my current function is: fun...

How to use an external .so in Kotlin I'm developing a simple Android app in Kotlin using Android Studio. I have an external .so file which was written in C++, I don't have the source code of this .so but I have the header file .h. My problem is that I'm not able to access the functions contained in the .so. I was reading a lot of topics about this but I'm not able to make it work. Basically I would like to use 2 functions from the .so : init() and getVersion(). The problem is that the init() function takes 2 parameters which I...

Android: How to open a specific calendar event with its ID I have a recyclerview which displays the events of the calendar, I want that when I click on an event it opens the event in the calendar

Is it possible to have the enum ordinal in kotlin without explicitly calling ordinal? In C enums are all numeric and you can reference the value just by the name. Example: #include enum week { sunday, monday, tuesday, wednesday, thursday, friday, saturday }; int main() { enum week today; today = wednesday; printf("Day %d",today+1); return 0; } Outputs: day 4 In Kotlin I would like something similar, at least being able to get rid of the .ordinal. Currently it's like this: enum class Week { sunday, monday, tuesday, wednesday, thursday, friday,...

Here SDK mapLoader.getMapPackageAtCoordinate return true but I never get result on callback I am using Here SDK and everything looks fine with initialization but when I call: val getMapPackageResult = mapLoader.getMapPackageAtCoordinate(GeoCoordinate(52.500556, 13.398889, 0.0)) to get maps packages to install, MapPackageAtCoordinateListener call back never get called! It is not the same when I call mapLoader.getMapPackages with no GeoCoordination! Any suggestion?

Implementation of Publish/Subscribe and Request/Response in Kotlin (targeting JavaScript) Novice Kotlin user here... Is there a way getting rid of the while loop at the bottom of the request(...) method? If possible I really want to avoid making request(..) a suspend method as I would like to call the code from Java Why doesn't the code work without the "yield()" call package com.example import kotlinx.coroutines.experimental.async import kotlinx.coroutines.experimental.yield class MessageMatcher interface Subscriber { fun onPublish(entity: Q) :...

Kotlin vs Java nested generics I'm having some trouble when trying to translate Java code with nested generics to Kotlin. Take this Java SSCCE as an example (please note the relation between S and T): public class JavaTest { private class JavaObjectContainer { public S obj; } private abstract class JavaSampleClass { private Class type; public JavaSampleClass(Class type) { this.type = type; } public Class getType() { return type; } public abstract void callMethod(S...

Pass Class Type as Parameter and Check Type Against Another Object in Kotlin I am attempting to write a method to wait for a type of activity to be present for my Espresso tests. I've seen examples of trying to wait for objects to appear on separate activities than where the test begins, but none have worked for me so far and I'm not keen to modify my production code with idling resources. In my method, I'd like to get the current activity, and then check if the activity is the specific type of class that I'm wanting. I'm basically modifying some code I found <a...

How to convert a Kotlin data class object to map? Is there any easy way or any standard library method to convert a Kotlin data class object to a map/dictionary of it's properties by property names? Can reflection be avoided?

Firestore, Give permission to read the document created by the one user to others I am using the firestore and want to apply the security rule for showing the document to the particular users to my document. Like i have created the Document D1 and want to give access to Users U1, U4, U8 and U334 to read. i.e. the document D1 will only be visible to these users only. I am unable to get any reference or help over this.