Android Studio: Kotlin Random Number Generator not working? I am using CardView in RecyclerView for displaying a list of City names. Along with the city name, I would like to add a curved square image containing a random background colour and the starting letter of the city name, just like the default image of our Gmail accounts. I have tried the following approach for generating a random index in the colours array and passing the colour to the ViewHolder class of my CustomAdapter. colors.xml #FFBB86FC #FF6200EE #FF3700B3 #FF03DAC5...

Kotlin Infinite Recursion val minesAround = checkIfMinesAround(row, column) if (!minesAround) { explore(row, column) ... private fun explore(row: Int, column: Int) { displayedMinefield[column][row] = Symbol.FCell.symbol for (i in determineRange(column, minefield.lastIndex)) { for (j in determineRange(row, minefield[i].lastIndex)) { displayedMinefield[i][j] = minefield[i][j] if (!checkIfMinesAround(i, j)) {...

How to post a selected image to a python API which will save the filename to mySQL db and then upload the image to an online folder This is my Kotlin code imageButton.setOnClickListener { val gallery = Intent(Intent.ACTION_PICK, MediaStore.Images.Media.INTERNAL_CONTENT_URI) startActivityForResult(gallery, pickImage) } } override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) { super.onActivityResult(requestCode, resultCode, data) if (resultCode == RESULT_OK && requestCode == pickImage) { imageUri = data?.data imageView.setImageURI(imageUri)...

Failed to initialize detector error in MLkits I want use mlkits in my app for object detection with kotlin but i get this errors E/MobileVisionBase: Error preloading model resource com.google.mlkit.common.MlKitException: Failed to initialize detector. how can i fix?

access child database in firebase always returns null using android studio & kotlin ive been having problems accessing this child database in firebase, it always return null, been searching up online for days and still got no answer...heres my code, im using kotlin and firebase auth = FirebaseAuth.getInstance() database = FirebaseDatabase.getInstance() databaseReference = database?.reference!!.child("users") val nikReference = databaseReference?.child("nik") val mainDB = nikReference?.child("jabatan") val user = auth.currentUser etEmailUserShow.text = user?.email...

Flood Fill Algorithm for Kotlin How would I implement the flood fill algorithm in Kotlin? I'm trying to use it for a two-dimensional array to change the surroundings of certain elements. I'm not using this for painting.

can anyone help me out why I am getting null value even there is no error in the code package com.example.myquizapp import androidx.appcompat.app.AppCompatActivity import android.os.Bundle import android.util.Log import android.widget.ProgressBar import android.widget.TextView here is my code class QuizActivity : AppCompatActivity() { private var progressBar : ProgressBar?= null private var tvProgress : TextView? = null override fun onCreate(savedInstanceState: Bundle?) { progressBar = findViewById(R.id.progressBar) on hover R.id.progressBar I get...

Uploading png error with MultipartBody.Part and RequestBody in Kotlin I am currently making a project for attendance application in Kotlin and I am trying to send a selfie image to the back-end for proof of attendance. I used MultipartBody.Part to send the image file and RequestBody to send the other stuff. @Multipart @POST("shiftentry/clockin") suspend fun clockin( @Header("Authorization") auth: String, @Part("shift_entry_id") id: RequestBody, @Part("location") location:RequestBody, @Part file: MultipartBody.Part ):...

my app keeps crashing in android studio for some random reason so basically, i am trying to develop an app in android studio but it keeps crashing. I got no idea why. can som1 help? This is the error code below: 2022-07-24 12:45:13.430 9938-9938/com.example.aviationista E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.aviationista, PID: 9938 java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.aviationista/com.example.aviationista.MainActivity}: java.lang.InstantiationException: java.lang.Class cannot be...

I can not open downloaded from the server on android add-on files minecraft I have a task, I need to download from the server add-on files for minecraft (.mcaddon, .mcpack, etc.) on android. For this I use DownloadManager. It downloads the files, but I can't open them in minecraft. I assumed that the problem is in MimeType, tried several solutions (application/x-freearc, application/octet-stream, application/zip, multipart/x-zip, application/x-zip-compressed) they did not work. i attach my code and the link to the file i use. <a...

Can't attach the adapter to the RecyclerView Why can't I attach the adapter to RecyclerView? Just constantly getting W/RecyclerView: No adapter attached; skipping layout Fragment class class Latest : Fragment() { private var mRecyclerView: RecyclerView? = null private var mAdapter: CurrencyAdapter? = null override fun onCreateView( inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle? ): View? { val asd = HashMap() asd.put("asd", 1.2) asd.put("as2d", 3.2) Log.i(TAG, "onCreateView: " +...

Is it safe to use Coroutines runBlocking() inside onDataSetChanged of RemoteViewsFactory? I am trying to fetch some latest movie images and display it in the Android app widgets, As per the requirement the widget should refresh every hour to get the latest movies images. Since I am using coroutines throughout the app, I need to use the existing retrofit services with suspend function to get the data. As per the Android documentation, its safe to do heavy operation inside onDataSetChanged of RemoteViewsFactory So I am using this method itself to fetch data from service instead of...

Query MongoDB Realm array only at first index I need to query MongoDB Realm from synced iOS and Android app. In Swift I can write something like this: let dictionary = realm?.objects(myReamlObject.self) let results = dictionary?.where { $0.senses.glosses.term == "the term I want" } or using predicate: let results = dictionary?.filter("ANY senses.glosses.term == %@", "the term I want") Both work well, but I don't want to check ALL senses.glosses.term. Every entry has (or could have) many senses and many glosses. I would like to...

How to get rid of the resource not found exception when clicked on item view on recycler view and instead of data and activity lauch, it crashes app I have built an app to learn the use of adapter and recycler view. It contains a recycler view and adapter, it uses data class to show data on clicked to an item of the recycler view, but the app crashes on runtime whenever I click on an item of the recycler view and showing java resources not found exception, could any one please help me out from this because I am a newbie to learning and debugging this 2022-07-24 16:00:14.903 11460-11460/com.example.planetapp E/AndroidRuntime: FATAL...

Kotlin Coroutine: Dispatchers inside Flow builder Extension functions that returns save Bitmap to device storage and returns result using sealed and class that represent its state. sealed class RequestStatus { data class Loading(val data: T? = null) : RequestStatus() data class Success(val data: T) : RequestStatus() data class Failed(val error: Exception, val data: T? = null) : RequestStatus() { val message = nullableErrorMsg(error.localizedMessage) } } fun View.createAndStoreScreenshot( appName: String,...

How is a Always on Display for Android coded? My smartphone (Samsung A21s) doesn't supoort the AOD of Samsung. So i tested several apps from the Play store. But I want an app,so i decided to code my own app, which allows me to choose my own background. I want to use the pictures from the gallery. I also want a music control for the AOD. I have a accurate idea of what I want, but I don't know how to code it. Does anybody know, how a AOD is coded? I use Kotlin and I'm working with Android Studio. Thank you for your help

Can you change the color of a textview in a recyclerview adapter after a certain condition is met in Main Activity? I have a basic function that displays the elapsed time every time the button is pressed. I cannot get the logic in MainActivity to transfer to the recyclerview adapter. I simply want the text output color to change to red after the time passes 5 seconds. I have tried to research how to do this for the past week and I cannot find the exact answer. I'm hoping someone can help. I have tried it with and without the boolean in the data class. I wasn't sure if that was required. Here is my code:...

How to implement seat booking in Android? I have this json response from the server: [ { "id": 12767236, "rowNumber": "01", "seatNumber": 1, "status": "taken" }, { "id": 12767237, "rowNumber": "01", "seatNumber": 2, "status": "available" } ... ... ... ] Basically it's a list of seats with a few properties, that's all the data I have. So, question is how do I show the seats and let user pick one like below? What component should I use? <a...

How can I save video to MediaStore by CameraX on Java? I saw this page to learn how to take some video captures and save them to a device. the Android official code: // Create MediaStoreOutputOptions for our recorder val name = "CameraX-recording-" + SimpleDateFormat(FILENAME_FORMAT, Locale.US) .format(System.currentTimeMillis()) + ".mp4" val contentValues = ContentValues().apply {...

Just another error of "Caused by: groovy.lang.MissingMethodException: No signature of method: " I researched on web and found different suggestions and even on stackoverflow some people asked similar questions but I couldn't find an answer that can solve my issue... What makes my build.gradle(app) to give this problem when I try to sync the gradle project? I would like to know what steps I should take in order to fix it. I use Android Studio IDE and Linux Debian os. Code: plugins { id 'com.android.application' id 'org.jetbrains.kotlin.android' } android { compileSdk 32...

Buffer size not large enough Facing this error java.lang.RuntimeException: Buffer not large enough for pixels Error Code Line : - val byteBuffer: ByteBuffer = ByteBuffer.allocate(1024*1024*5) bitmap.copyPixelsToBuffer(byteBuffer) I think its the error is Buffer Capacity is small for my image to copy bitmap but than what is the good approach? How much buffer capacity I must assign to not have the error?

Ktor server, a correct way to receive messages from websocket I'm new in Ktor-server and don't fully understand how web sockets receive messages. I found several solutions in different sources. (try\catch and webscoket blocks are omitted) while(true) way while(true){ val incoming = receiveDeserialized() MessageService.newMessage(incoming) } consumeEach way incoming.consumeEach { frame -> // process frame } flow way incoming.receiveAsFlow().filterIsInstance()...

divide a list in Kotlin by a rule Let's say I have a list of strings which represent people and some properties about them in Kotlin. I know the first element in the list will start with "PSN" prefix and the next list elements will be properties about that person. After X lines I will see "PSN" prefix again and so I'll know this is a new person. I want to group the list elements by the person they belong to. Original list example: val originalList : List = ["PSN Elvis Presley", "elvis property 1", "elvis property 2", "PSN...

android complex ui design for shopping apps I have requirement to implement complex UI design (Main scene for slot machine), so i am making research about the best way to do this.i want to design something like shop and when user take action like buying something and press button the item move to box and box close . where i can start from . i think that i can use unity . but i don't know C++ can i use java with it? i'm android developer.

What should I add in my code so that every time I check one of the recyclerview items it will display his numer of calories AdapterItem: class AdapterItem( val userList: List): RecyclerView.Adapter() { class ViewHolder(itemView: View):RecyclerView.ViewHolder(itemView){ var numeLista: TextView var caloriiLista: TextView = itemView.findViewById(R.id.caloriiLista) init{ numeLista=itemView.numeLista caloriiLista=itemView.caloriiLista } } override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder { var itemView =...

Fragment is not getting popped using navigation graph I am building an app where first time it opens fragment1 to get user details and once user forwards to next fragment2, I am saving the details and setting a boolean variable isUserRegistered to true in SharedPreferences so that when the user opens the app next time, he/she will be directly taken to the fragment2. I am using using navigation graph to handle these things. Following is the code: //declared at the top in onCreateView() of fragment val prefs =...

Kotlin: Styling Text in Snackbar with SDK later than 28 I am working on a Kotlin project and I wish to style the text in a Snackbar, specifically the text font. I have been to many websites that address this problem, but they all use this line in the Snackbar body: val snackbarTextView = snackbar.view.findViewById(android.support.design.R.id.snackbar_text) as TextView The problem setting the TextView with this code, is that it only works if your project targets SDK 28 or older, and legacy libraries are enabled. I am targeting SDK 30 and then the...

Google wallet is not working Android kotlin I am trying to create an application like this to save my ticket passes in google wallet https://codelabs.developers.google.com/add-to-wallet-android#0. I have done all steps but I couldn't get the result. Actually, I have a google pay on my mobile but it shows "Unfortunately google...

how to synchronise room database of android app with remote server I'm working on an android app with an MVVM pattern. I have to sync my local database with a remote server. but I have no idea how to do it. I have used the room database.