ObjectBox, sum a property by grouping another property Imagine I have this table: tagId amount 1 100 1 150 2 200 2 250 And i need to sum the amount by grouping the tagId. In SQL we can do this by: SELECT tagId, SUM(amount) FROM orders GROUP BY tagId; Query result: tagId SUM(amount) 1 250 2 450 How can I get such results in ObjectBox ?

How to make efficient list from particular object in kotlin Hey I have list of object in which I want to combine title property value into list of object. I did this successfully without any problem. My main questions is there any better approach to do in kotlin which helps in efficient, better memory management and everything when eventList is bigger in size. CombineList.kt fun main() { val newList = mutableListOf() val eventList = createData() eventList.forEachIndexed { _, event -> val title = event.title if...

Is there a way to capture the APP state in ram from Android? What i'm trying to do is get the state of ram in Android and save it to reuse later. Just like emulators with NES games. The idea is to capture the state of the app, store it, read it and set it up on future.

Google Wallet Console - Class ID I am trying to integrate google wallet loyalty cards into my application. I succesfully tested using the ids from the demo project . Now I want to prepare for production. I received access for google wallet but I do not know how to complete "class id" . Did not find in any documentation . Thanks all for your time

Query with 2 joins and subquery using kotlin-exposed I have such SQL query: SELECT parent_id, e.season_number, max_seasons.max_episode_number, b.start_year FROM episodes e JOIN basics b USING(title_id) JOIN ( SELECT e.season_number, max(episode_number) AS max_episode_number FROM episodes e WHERE e.parent_id = 944947 GROUP BY e.season_number, parent_id ) AS max_seasons USING(season_number) WHERE e.parent_id = 944947 AND e.episode_number = 1 And I need to translate it to query using Exposed library and kotlin. I extracted sub-query...

How can I write to only one user with an existing WebSocket connection instead of to all users? Here's what I have: Here, incoming messages are sent to all users. fun Route.chatSocket(roomController: RoomController) { webSocket("/chat-socket" ) { val session = call.sessions.get() if (session==null) { close(CloseReason(CloseReason.Codes.VIOLATED_POLICY,"No session")) return@webSocket } try { roomController.onJoin( username = session.username, sessionId = session.sessionId, socket =...

Concise way to find and remove items from a mutable list kotlin I have 2 mutableLists for new countries and current countries I want to remove the countries from listOfCurrentCountry only if they exist in listOfNewCountry For this I am using the removeIf and firstOrNull to check if the listOfCurrentCountry is in the listOfNewCountry. val listOfNewCountry = topsProductFilter.items val listOfCurrentCountry = selectedCountryItemsStateFlow.value listOfCurrentCountry.removeIf { currentCountry -> val result =...

Mockito deep stubs not returning the mock I want I'm trying to test my app that relies on the GitHub api. Here is the test code : val github: GitHub = mock(defaultAnswer = Answers.RETURNS_MOCKS, verboseLogging = true) val ghTreeEntry = mock() whenever(github.getRepository("foo/bar").getTree("main:data") .tree).thenReturn(mutableListOf(ghTreeEntry)) whenever(ghTreeEntry.path).thenReturn("file.yml") doStuff(gitHub) However my code which in the end does...

Combine object data value into single string in kotlin Hey I have object of Event. I want to combine all property value into single string. I did this without any problem. I want to know is there any better way to optimise this code in memory, efficiency etc. SingleEventString.kt fun main() { var newString: String? = null val eventList = createData() eventList.forEachIndexed { index, event -> val title = event.title val status = event.status if (!title.isNullOrEmpty()) { newString = if(index == 0){...

Encryption of a file in kotlin returns HEADER_TOO_LONG i'm porting an old java android app to a kotlin approach. What i'm trying to achieve here is to encrypt a file using a .der file Here what i did so far, as you can see i basically adapted the code to work in a kotlin base Kotlin val encodedKey : ByteArray = ByteArray((publicKeyFile.length()).toInt()) val publicKeyFileIS = FileInputStream(publicKeyFile) publicKeyFileIS.read(encodedKey) // create public key val publicKeySpec = X509EncodedKeySpec(encodedKey) val kf =...

Android databinding with Kotlin map This is a basic question that for some reason Google doesn't seem to have the answer. I'm trying to use a Kotlin map object with databinding for xml. How the heck do I import the Map object in the xml? Using name="formIds" type="kotlin.collections.MapsKt" /> doesn't import the map object. I get a Failed to resolve Bracked Expr formIds["Submit"], target: kotlin.collections.MapsKt when I try to use the object. I create formIds as follows: val _formIds =...

Android bitmap file being displayed on ImageView, but it's empty on debug/log I have a simple Activity with a button where I can pick image from gallery, and show it in a ImageView. When I pick the image from gallery, it works normally and shows normally in my ImageView, but on Log.d and during the debug mode, the variable imageBitmap is "" (empty), and I can't use this on my method redirectSaving(), where I expect receive something. See the code snippet below: private fun treatImageFromGallery(it: Intent) { val selectedImage: Uri? = it.data val...

How to download and install an update in android studio app I need to download and install new updates from a URL that contains my apk file...The usual procedure is to check if there's a new version then download it and install it

Android Compose fillMaxWidth issue Why the width of red circle equal to with of gray area? Here are my code and result, Hope someone answers. @Preview @Composable fun testContent() { Scaffold { paddingValues -> Box( modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center ) { Column( modifier = Modifier .fillMaxWidth(1f) .aspectRatio(0.8f) .clip(RoundedCornerShape(size = 6.dp))...

How to make a 3D model viewer android app? I'm trying to make my own 3d viewer app. I just want it works like, Open an app (tap on my smartphone screen), Show a 3d model, Close the app when the back button is tapped. Actually, I made an app that is working like my idea. Here is the code that I'm using. val sceneViewerIntent: Intent = Intent(Intent.ACTION_VIEW) val intentUri: Uri = Uri.parse("https://arvr.google.com/scene-viewer/1.0").buildUpon() .appendQueryParameter(...

Compile libraries for Kotlin android,rust and go This question is exploratory in nature, not sure if this fits stack overlflow Q&A. Context: I have a library written in golang that I need to compile for multiple services to use. These services are in Kotlin android,Rust,Golang. The only option I am aware of is using something like SWIG to compile the go library for different languages. Problem: I don't think SWIG works for Kotlin. I am trying to fish for the best methods to do this and different approaches this can be done.

Finding the absolute value of a Byte variable in Kotlin or Java? Why isn't there any function in the standard library of Kotlin/Java for taking the absolute value of a Byte/byte variable? I'm I missing something? Math.abs() is only defined for int, long, double and float. For context: in the audio world you can run easily into byte arrays representing the amplitude. I'm interested in calculating the average of the absolute values of a byte array. I know I can cast it to an integer and take the absolute value of that, but I would still be interested why is...

How can I give the recyclerview dynamically constraint? I have layout with a recyclerview and adView. If the ad loads, it looks fine, but if it doesn't, there's a huge gap. If the ad doesn't load, the recyclerview won't have gap, how can I do it? Layout:

org.jetbrains.kotlinx:kotlinx-coroutines-android vs org.jetbrains.kotlinx:kotlinx-coroutines-android:*-native-mt New to Android development and I’m confused between these two libraries and why I would want one over the other for Android. I’ve reviewed the following: • https://kotlinlang.org/docs/multiplatform-mobile-concurrency-and-coroutines.html#multithreaded-coroutines • <a...

how to fetch current location with permission android kotlin I'm back after a while to android development. I want to have my current latitude and longitude and display it with a toast, unfortunately, it doesn't work . I added location permissions in AndroidManifest.xml And here is my MainActivity.kt : class MainActivity : AppCompatActivity() { private lateinit var fusedLocationClient: FusedLocationProviderClient override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState)...

How to handle exception and return main object in RxJava2 I am trying to return the same parameter if there is any exception in the function but it always return the error not the object. private fun setPackName(aPack: Pack): Observable { return nameRepo.getNameFromDb(aPack.verifyObject) .toObservable() .map { aPack.name = it.name } .map { aPack } .doOnError { Observable.just(aPack) } } return Observable.just(aPack) } viewModel.setPackName(pack) .doFinally {...

Firebase realtime database &amp; android To-do app: how to get reference (id) from specific node in db How to get "taskName" value (his id) from firebase db (node in red on picture) to remove to-do task. Each task is represented in recyclerView. [FirebaseDatabase.getInstance().getReference("Users").child(uid).child("Tasks").child(** MISSING taskName refrence (ID) *).removeValue() Toast.makeText(getActivity(), "Task successfully deleted !", Toast.LENGTH_SHORT).show()...

Why can't Gradle resolve the Kotlin Gradle plugin I'm trying to manage my dependencies in Android Studio and it cannot resolve the Kotlin gradle plugin. I've tried manually adding it to my build.gradle using the code from Maven Central and adding it using the project structure feature in Android Studio. As far as I know everything here is correct, so it should just download it and build. //Kotlin dependencies implementation 'org.jetbrains.kotlin.jvmorg.jetbrains.kotlin.jvm.gradle.plugin1.7.0-RC' implementation...

How to resize drawable/Imagespan in a textview/spannable string I'm trying to add some images to a textview, and found out how to do that simple enough using Spannable String. Works fine, however, if I want to resize the image (either smaller than original, or larger than original), I can't seem to get it to resize. There's some other similar questions that seem to answer this, however, trying to convert them to Kotlin, I'm unable to get anything to work. <a href="https://stackoverflow.com/questions/5561981/how-to-display-image-in-androids-textview">How...

Kotlin: Environmental chronometer timer handled from 2 fragments I have two chronometers in two fragments and I need them to have the same associated time. However, right now the behavior is that the first chronometer works correctly until I change the fragment and its time is reset. The second timer doesn't work and I would like the first and second timers to receive the same time and not be reset every time I change fragments. I would also like to be able to access the chronometer time from any other fragment of the application and if I wish I could...

arraylist .add Not working not adding in ArrayList [duplicate] I have been making an Music Streaming App in that for some reason .add in ArrayList is not working, Here is the Code :- var media: MediaPlayer = MediaPlayer() fun getTrack(URI: String) : ArrayList{ val tracklist: ArrayList = ArrayList() media.setAudioStreamType(AudioManager.STREAM_MUSIC) val requestQueue = Volley.newRequestQueue(App.getContext()) val jobject: JsonObjectRequest = object : JsonObjectRequest( Method.GET, URI, null, Response.Listener { response ->...

encode PBEKeySpec / decode pbkdf2Sync I have to use the "PBEwithSHAAND256BITAES-CBC-BC" why algorithm, I do not know on the server side node.js the 12345 string can not be decoded kotlin code inpit "12345" after encrypt = "eIVEpNnDQ/0nx7wJ13RBig==" fun encodeStringAESToken(saltAES: String, baseCode: String): String? { val iv = ByteArray(16) val ivParameterSpec = IvParameterSpec(iv) val secretKeyFactory = SecretKeyFactory.getInstance("PBEwithSHAAND256BITAES-CBC-BC")// val keySpec: KeySpec =...

How to Daynamically add Keys and Values to a mutable map in kotlin I am facing a strange error I can't figure out why exactly this happens, as I have a mutableMapOf and I want to keep adding keys and values to it dynamically every time they add new items. what happens is that no matter how much data its entered it only stores the last items, If I hard coded the data it stores it normally, but within the scope of the method it doesn't work and I cant figure out why? private fun showDialogBody() { val dialog = Dialog(this)...

I Have Several Problems In Gson Library in (Jetpack Compose) Hello Stackoverflow community I Would like to fetch data from this Rest Api: https://adeega.xisaabso.online/Api/android_today_dashboard.php but unfortunately i have several problems in my application so how can i solved, i am new in jetpack compose here are my problems: No value passed for parameter 'Amaahda' No value passed for parameter 'Expenses' No value passed for parameter...

Kotlin How to read and write CSV file Could you give me most simple code in Kotlin ? I tried to find good example in seraching with Google, after 5 hours or more, I could NOT find what I want. from chk[1] to chk[20] not yet : 0 done : 2 // 2 is similar Victory Sign. for example, if solved Quiz Number "1" chk[1] = 2 var chk_Q: Array = arrayOf ( 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,...