How to use graphview with graphview library I am trying to create a graph with the graphview library and create a simple graph When I included the dependency in my build.gradle, I got an error that I can't solve. build.gradle (.app) plugins { id 'com.android.application' id 'org.jetbrains.kotlin.android' id 'kotlin-android' id 'kotlin-android-extensions' } android { compileSdk 31 defaultConfig { applicationId "com.example.lightrdetect" minSdk 23 targetSdk 31 versionCode 1...

How to connect with other device via Bluetooth programmatically android kotlin I would like to connect with other device programmatically via Bluetooth in kotlin, I tried to find methods but I couldn’t find any good and new methods in kotlin. How to do it?

How to build an intermediate code generator for Kotlin? I am only aware of how to make lexical and syntax analysers for Kotlin [The lexical analysers and syntax analysers created can be found here :- https://drive.google.com/drive/folders/1uT6MOe5zONkvNKyUw8Knq2dmzSK7po5m?usp=sharing ]. I am looking for a step by step guide on how to proceed ahead and create an intermediate code generator that produces three address code and has associated semantic actions. Please help.

Kotlin Ternary conditional operator to typical if-else Can someone turn this to if-else statements in Kotlin so that I can get an understanding of the code? return email != null ? email.isEmpty ? "Please enter your email!" : RegExp("^[a-zA-Z0-9+_.-]+@[a-zA-Z0-9.-]+.[a-z]") .hasMatch(email) ? "" : "Please enter a valid email!" : "Please enter your email!";

Android EditText: Smooth expanding animation when new line is started I have noticed that Telegram has a smooth animation in their chat EditText when a new line is inserted / started. Below I have two GIFs. The first is Telegram, the second is my app. How can you achieve such an animation effect? I tried to google it, but I didn't find anything. I know Telegram is open source, I tried to find out from their...

Generate 72 hours of timeslots with 15 minutes of interval in android I am trying to generate an array of 72 hours timeslots with 15 minutes of interval but it starts with 00:00 after 24 hours, so basically it prints whole 24 hours timeslots 3 times, but i want to start from 0015..2345..2400..2445..2500..2515..72:00 I have less experience working with Calendar APIs, Here is my code, val start_duration = "00:15" val end_duration = "72:00" val _start_duration = durationFormatter.parse(start_duration) val calenderStartDuration...

button.setOnClickListener is crashing my app. Kotlin 1.3.72 So firstly I know that kotlin android extensions are not supported anymore. I will change that later. First I want to make sure my app works and has what it needs then Ill converge over. I am somewhat new to android studio so there is a chance I missed something simple. I did Import button and toast. My app works fine if I remove the button onclick listener so I assume it must be the culprit. Main activity button1.setOnClickListener { Toast.makeText(this@MainActivity,...

How to fix java.lang.ClassCastException: androidx.emoji2.text.SpannableBuilder cannot be cast to java.lang.String ? cannot set text to Google Material [duplicate] I want to set text programatically to a Google Material Edit Text, but I get this error: java.lang.ClassCastException: androidx.emoji2.text.SpannableBuilder cannot be cast to java.lang.String Here is the layout snippet: And this is how I tried to set the text, whether it was using name_input or edit: binding.nameInput.editText?.setText("TEST") /n binding.edit.setText("TEST") I've set android:bufferType="spannable" as explained in the latest answer <a...

How to Fix "Registrar cannot be converted PluginRegistry" I'm trying to create my custom plugin for Flutter on Kotlin. I see this error when i run my app. example\android\app\src\main\java\io\flutter\plugins\GeneratedPluginRegistrant.java21 error: incompatible types: Registrar cannot be converted to PluginRegistry I created an issue to GitHub : https://github.com/flutter/flutter/issues/99899

java file not imported in my kotlin project Please I am working with kotlin and when I tried to move from one Activity to another using an intent, i got an error on the java keyword which says "unresolved reference" when i click to see some suggestions they told me to create an Extension property of Kclass.java. I don't really know what is the issue as i have tried so many suggestions but still cant solve it. Here is the code. class WelcomeActivity : AppCompatActivity() { var firebaseUser: FirebaseUser? = null override fun...

start another activity and pass the image back to the first activity I have the MainActivity from where I am starting the SecondActivity. There, I select an image from gallery and I want to push it back to the MainActivity. MainActivity: override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) ... srButton = findViewById(R.id.super_resolution) srButton.setOnClickListener { view: View -> val intent = Intent(this,...

Zebra write RFID in Android Kotlin preforming correctly with some tags but not others I am working on a inventory management system where it's required to write asset ids (with length of maximum 17) in to an RFID tag. First the problem was that when I write on a tag an ID with shorter length than the already written one, it keeps the non overridden characters in the tag. for ex: if the tag has the ID "123456789" written on it and I write id "abc" on the tag. The tag's asset id becomes abc456789. I tried killing and erasing the tag before writing but it didn't work. After that,...

How do I read json data (Latitude, Longitude) and convert it to polyline (Kotlin) I have a list of lat,long data in json format (AIRPORTS.jsin), I want to read it and convert it to polylines. After writing a function to do that, It does not show in the mapActivity This is what I have done fun getPolylines(fileName: String?): MutableList? { var polyline: LatLng // array list of lines init val polylines = mutableListOf() val inputStream = fileName?.let { application.assets.open(it).bufferedReader() } var Json_string...

Custom Listview whole row is not selected in Dialog Fragment in kotlin using viewbinding Data Set custom listview in Dialog Fragment using BaseAdapter. when select list item then only text item selected, whole row is not selected. CustomDialog.kt class CustomDialog(val servList: ArrayList) : DialogFragment() { override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? { val inflater = context?.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater val binding =...

Android launching intent retrieved by webview (convert string to intent) I am building an in-app browser for handling firebase authentication with external providers (for example Microsoft login). I have button in my main page which calls auth.startActivityForSignInWithProvider(this, provider).addOnSuccessListener{} and it launches the activity with a webview. The issue is once I finish completing the login with the provider, the webview receives a url (which is a string) showcased below. How can I parse this string into an intent in-order to launch it?...

Cant set text to Edit Text Material , give solution to error please Error java.lang.ClassCastException: androidx.emoji2.text.SpannableBuilder cannot be cast to java.lang.String NOTE: @GHH user instantly closed my previous post even though he didn't give me a solution. There is a difference between my post and the so called "duplicate" answer here because it doesn't give me the solution as I tried. I want to set text...

How to update two types of app widgets using Alarm Manager? I want to make two different types of appwidgets, which would update at the exact time using Alarm Manager... Every type of the appwidgets has own layout, xml file with meta data and AppWidgetProvider. Inside every AppWidgetProvider for each type of widgets in onReceive, onEnabled, onDisable methods I have the code for updating app widgets with Alarm Manager. The examples for one type of the widgets are below. (Similar code is for another type) onEnabled: override fun onEnabled(context:...

Use Int as a parameter for Kotlin data class got a bit of a problem with creating a data class. First post, and a bit of a noob - be gentle :) I'm trying to create a Kotlin data class to handle some responses from an API we use; the response of which looks a bit like this: "data": { "devices": { "600": [ { "device_id": "[deviceId]", ... What I'm having trouble with is the "600" bit - I can't find a way to create the data class with this as a parameter. Each time I declare the...

I need to develop a game which players will be using to practice their arithmetic calculative skills I am stack on these tasks: Clicking on the New Game button, the user will be presented with the game screen which they interact with. The screen displays 2 random arithmetic expressions one on the left and one on the right and 3 buttons below them (Figure 1). Each of the 2 arithmetic expressions involves 1, 2, 3 or 4 terms and it should be random (i.e. not hardcoded, or fixed, neither for the terms nor for the operations). Every time the game screen reappears, the user is displayed with 2 new...

How to reset a Random Number in Kotlin I tried to make Guess the Number game that the number generate using this code: var randomNumber: Int = Random().nextInt(50) and not only that, I tried to put the retry button and reset function: fun initializeGame(){ status.text = "" tGuess.text = "" randomNumber btnGuess.isEnabled = true guessCount = 0 tCounter.text = "The Chances Remain: $guessCount / $guessLimit" } The problem is I can't reset the random generator. Sorry for...

What is parameters in constructor (context, attrs)? How I can create new object this class? Java and Kotlin I try create sound spectrum, I created class view, which show spectrum, but to it work, i must create new object this class My View class: class WaveformView(context: Context?, attrs: AttributeSet?) : View(context, attrs) { private var paint = Paint() private var amplitudes = ArrayList() private var spikes = ArrayList() private var radius = 6f private var w = 9f init { paint.color = (Color.rgb(244, 81,30)) } fun addAmplitude(amp: Float){...

ContextCompat ANR reports multiple times on firebase I got a ANR report on firebase. Its count is increasing and I cannot figure out this since it does not mention anywhere on my code. This is the ANR on firebase console. main (native): tid=1 systid=5789 at libcore.io.Linux.access(Linux.java) at libcore.io.ForwardingOs.access(ForwardingOs.java:72) at libcore.io.BlockGuardOs.access(BlockGuardOs.java:73) at libcore.io.ForwardingOs.access(ForwardingOs.java:72) at android.app.ActivityThread$AndroidOs.access(ActivityThread.java:7766)...

FeedRecylerAdapter must extend android.app.activity:13 / I am writing a news app and using adapter and ı am getting this error in Android Manifest : 1-FeedRecylerAdapter must extend android.app.activity:13 / 2-This class should provide a default constructor(a public constructor with no arguments) the code is here : class FeedRecylerAdapter (private val postList: ArrayList) : RecyclerView.Adapter() { class PostHolder(val binding : SourceNewsLayoutBinding) : RecyclerView.ViewHolder(binding.root){ } override fun onCreateViewHolder(parent: ViewGroup,...

Ktor framework study resources recommendations I am new to Ktor and would like recommendations for any resources (courses, books, blogs, or youtube videos) that would help me learn it well and understand the fundamentals of the framework. Thanks in advance.

how to resolve plugin update issue Please I dont really know what is wrong with my Android studio, I updated kotlin plugin recently and it started giving me some issues. The code is build successfully but am still getting all these red lines even when the error is not affecting the build. Here is my gradle files. The red lines is so frustrating even when the code is compiling successfully // Top-level build file where you can add configuration options common to all sub-projects/modules. buildscript { ext.kotlin_version =...

Why can't I create two databases with SqlDelight? Recently I tried to add a second databse in my app and got this error when tried to do so on line where android{...} starts in build.gradle: A problem occurred evaluating project ':app'.

No signature of method: build_ez70an6l6aemlaxhrb67ugars.android() is applicable for argument types: (build_ez70an6l6aemlaxhrb67ugars$_run_closure1) values: [build_ez70an6l6aemlaxhrb67ugars$_run_closure1@261d89e1]

* Try: Run with --debug option to get more log output. Run with --scan to get full insights....

Return a String inside the companion object function inside the CoroutineScope In the MainActivity in have a companion object function which consumes the variable outside the function. In the functioni would like to return the data as string inside the CoroutineScope. Here is the code:- class MainActivity : AppCompatActivity() { private var data = “myName” override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val data = getMyOuterValue() Toast.makeText(this@MainActivity, data,...

Kotlin gives multiple "unresolved reference" errors in Android Studio I try to follow developer.android.com/jetpack/compose/text#displaying-text and get Unresolved reference: remember Unresolved reference: mutableStateOf Unresolved reference: OutlinedTextField Unresolved reference: it What am I doing wrong? The whole function: @Composable fun SimpleOutlinedTextFieldSample() { var text by remember { mutableStateOf("") } OutlinedTextField( value = text, onValueChange = { text = it }, label = { Text("Label") } ) } Imports:...

Hello! How to play two videos one after another in Kotlin? How do I swtich from a video to another whithout a click of a button?

Create Single from other singles and completable I have a repository that returns Single. This repository calls a datasource that creates a network call to return these objects from somewhere else (datasource returns Single) . Once this data is acquired I need to make a local query to compare with the local database on a 1 to 1 basis (for each Table a new local query needs to be consulted and the original Table will change, local query returns Single). Once that item has changed I need to save it locally (it returns Completable). And once...