custom sqrt algorithm optimising (yes, this is a leetCode problem) the problem: Given a non-negative integer x, compute and return the square root of x. Since the return type is an integer, the decimal digits are truncated, and only the integer part of the result is returned. Note: You are not allowed to use any built-in exponent function or operator, such as pow(x, 0.5) or x ** 0.5. my solution: class Solution { fun mySqrt(x: Int): Int { var start = 1 var end = x var ans = 0 while (start...

How to use the latest version of CardStackView in Android Kotlin? I tried using this github repo (https://github.com/yuyakaido/CardStackView) in my android app but I couldn't get it to work. val cardStackView = findViewById(R.id.card_stack_view) cardStackView.layoutManager = CardStackLayoutManager() cardStackView.adapter = CardStackAdapter() The setup code in the documentation no longer works fully. The first line works but the second and third lines result in errors...

Is it possible to extend a class with a static method in Kotlin or Java? I would like to create a Java Instant from a Long representing a nanosecond epoch. While Instant has nanosecond precision, the only way to do this would be to use the nanoAdjustment argument of Instant.ofEpochSecond: val nanos: Long val instant = Instant.ofEpochSecond(0, nanos) But it would be more convenient and readable if I could simply do: val nanos: Long val instant = Instant.ofEpochNanos(nanos) To achieve this, the only solution I could think of was package util object Instant {...

How can I take a map with percentages to a value in Kotlin? So I have a map of items to probability. ----------------------------------- | enum_example | int_ probability | | ENUM.ITEM1 | 89 | | ENUM.ITEM2 | 10 | | ENUM.ITEM3 | 1 | ----------------------------------- And I want to take this data, and use it to get each item that percentage of time. So, 89% of the time I get ITEM1, 10% of the time I get ITEM2, and 1% of the time I get ITEM3. I want to always get at least one of the items.

The return value dosn't give me a number in Kotlin This question is to find the sum of the longest path of a tree in recursion. Here is my code that I have come up with. class TreeNode(var key: T){ var left: TreeNode? = null var right: TreeNode? = null } fun maxPathSum(root: TreeNode): Int{ val leftChildPath = (root.left?.let { maxPathSum(it) } ?: Int.MIN_VALUE) val rightChildPath = (root.right?.let { maxPathSum(it) } ?: Int.MIN_VALUE ) val maxChildPath = leftChildPath + rightChildPath return root.key + maxChildPath }...

Flutter local_auth platform exception requires activity to be a fragmentactivity flutter I am using the plugin local_auth to let users authenticate by their fingerprint, now I know that there are some changes that need to be done on 'mainActivity.kt' so the plugin gets working without the error local_auth plugin requires activity to be a fragmentactivity flutter but the problem is I am using google_ads plugin too and I am registering native ads with it that using the context inside the class FlutterActivity so I can't change it to FlutterFragmentActivity or I am getting...

I can't find why is my data not being displayed in firebase real time database I have debugged this and it seems to be correctly linked and all data is saved as it should but when comes time to add to the server it doesn't do anything ## What are some things that I am doing wrong and what can I change for it to work? This is written in kotlin with a firebase real-time database and yes, I have changed the permissions in firebase to be a able to read and write class AddItemToDataBasePage : AppCompatActivity() { private lateinit var etName : EditText private...

Convert map of probabilities to value So I have a map of items to probability. ---------------------------------------- | enum_example | int_ probability | |______________________________________| | ENUM.ITEM_ONE | 89 | | ENUM.ITEM_TWO | 10 | | ENUM.ITEM_THREE | 1 | ---------------------------------------- And I want to take this data, and use it to get each item that percentage of time. So, 89% of the time I get ITEM1, 10% of the time I get ITEM2, and 1% of the time I...

I got an error in android 11 saying no such file or directory, can someone help me with this java.io.FileNotFoundException: /storage/emulated/0/DocScanner/doc_img/1.jpg: open failed: ENOENT (No such file or directory)

How to create watermark text effect in jetpack compose I would like to create a watermark effect in my app using text as shown in the picture below. I achieved this by using canvas and bitmap, is there any other reliable way to do this? Here is my composable function @Composable fun WaterMark( modifier: Modifier = Modifier, content: (@Composable BoxScope.() -> Unit)? = null, ) { val watermarkText: String = "some mutable text" val paint = Paint(Paint.ANTI_ALIAS_FLAG) paint.textSize = LocalContext.current.dpToPx(24).toFloat()...

how to save the reached level in a quiz app I'm new to kotlin and android app developpement in general and I want to make a Quiz app with jetpack compose not XML, and this app has multiple levels and when the user starts the quiz if he decides to stop playing in a certain level and quit the app i want to save that level so next time when he come back to play he's gonna start from the same level he stopped. I've tried to use preference datastore but it doesn't seem to work. this is my Datastore class: <a...

Intellij running multiple kotlin files inside project, instead the one selected Learning Kotlin and IntelliJ, Before yesterday if I wanted to run one single .kt file, it was all good. Many ways to do it. I was doing various exercises, all in the same file exercises.kt. After finishing a code, I would just transform it into a comment and start the next one in the same file. After many exercises, I decided to create a .kt file for each one. But, now, when I run a single file for one exercise Intellij is running ALL files inside the project, instead of just the one I selected.

What's different between words "convert", "transform" and "mapper"? What's different between words "convert", "transform" and "map"? To copy properties from beanA to beanB, use convert or transform or map? To parse a String to a formated Object (such as JsonObject), use convert or transform or mapper? In Kotlin there are many params called transform which is used to map a type to another type such as Iterable.map(transform: (T) -> V) (in java they commonly called mapper).

OnCreate for sqlite databse in android is not called automatically even though I am using writabledatabase I am new to SQLite and trying to create an SQLite database. Still, the problem is that even though I am using writabledatabase before inserting the data in the addData() method I still get the error "no such table". I don't know where the bug is. This is the code for the database class. Of course, I am creating DBHelper in the MainActivity and I pass this as the context. class DBHelper(context: Context, factory: SQLiteDatabase.CursorFactory?) : SQLiteOpenHelper(context, DATABASE_NAME,...

Gradle plugin must not include version I have a multiproject gradle project project_android project_lib app project-lib is in its own git repository which I added to to project_android using git subtree. I'm stuck. In order to build project_lib by itself, I need to specify a version for this plugin. If I don't have the version plugins { id 'org.jetbrains.kotlin.jvm' } I get this error when building * What went wrong: Plugin [id: 'org.jetbrains.kotlin.jvm'] was not found in any of the following sources: - Gradle Core Plugins...

Compress image in webview before upload android kotlin I have created webview view in Android Kotlin with two options i.e. by opening file manager or camera help me add it before uploading from both options and compress data directly so the image size is small following code for webChromeClient() binding.webview.webChromeClient = object : WebChromeClient() { @SuppressLint("QueryPermissionsNeeded") override fun onShowFileChooser( view: WebView, filePath: ValueCallback,...

Why can't I integrate the Java templating system Pebble? It looks so simple My pom.xml has: sonatype-public Sonatype Public https://oss.sonatype.org/content/groups/public true and io.pebbletemplates pebble-spring-boot-starter 3.1.5 then I rm -rf ~/.m2/repository and mvn clean package compile but...

What is the proper way to wait for a Flow to collect? I need to have some data loaded from a database in my View Model when is it created. Since the data comes in the form of a Flow, I'm passing it to a lateinit variable using collect. However, I need to further process the data after it is loaded in it, but I don't know how to wait for the data to actually be loaded. This what I have so far: class MyViewModel: ViewModel() { ... private var _state = MutableStateFlow(MyState()) var state = _state.asStateFlow() private val myDataSource:...

How can the RecyclerView adapter talk back to parent layout? I got a parent layout activity_main.xml layout with multiple views inside it, one of which is the RecyclerView view. What happens is that, within the recycler view, there are buttons that, once the user deals with, I would like things to happen in the parent layout that is activity_main.xml. For example, if I press a button on a ViewHolder item inside the child RecyclerView, in some cases, I would like changes to happen in the parent activity_main.xml layout. However, my problem is that I...

Room databasebuilder not enough information to infer type variable T I'm new in room database and I have problem with Room.databasebuilder that shown an error not enough information to infer type variable T. Here is my code @Database(entities = [ThreadTable::class, GambarThreadTable::class], version = 2, exportSchema = false) abstract class ThreadDb: RoomDatabase() { companion object{ private var instance: ThreadDb? = null fun getDb(context: Context): ThreadDb{ if (instance == null){ instance =...

how can I save the textView on the selected date in CalendarView? I want to choose the date in the CalendarView and, I write my content on the date's EditText. And I want to save the EditText's content into the TextView. but in my code, if I choose September 1st and write content and save it, I can see the content on September 2nd, too. how can I fix it..? I can't do English, android well, sorry class SmartMirrorToDoListFragment : Fragment() { lateinit var calText: TextView lateinit var todoWrite: EditText lateinit var save: Button lateinit var diaryText:...

Can't launch Fragment from RecyclerView adapter There is a code for the NameListHolder class located in the RecyclerView adapter class NameListHolder(val binding: NameListItemBinding) : RecyclerView.ViewHolder(binding.root) { fun bind(paginationLocalModel: PaginationLocalModel, position: Int, context: NameListFragment){ binding.name.text = paginationLocalModel.name itemView.setOnClickListener{ val fragment = DescriptionFragment() val bundle = Bundle() bundle.putInt("position",...

Kotlin - Custom JSON object For my Kotlin android application, I need to form a custom JSON object in the below format, Please help me on this. Values and objects are dynamic, it will change as custom. and i want to form and send as JSONobject to some other method. { "RentalSettings": { "balance": 1000, "num": 100, "is_vip": true, "name": "foo" } } I tried to create it like this.. but showing error.. JSONObject({"RentalSettings":{"RentalSettingsStatus":"Success", "Pin":pinNo.toInt()}})

Does coroutine change spring boot from 1 thread per request to multiple request per thread? I am a newbie to reactive or coroutine concepts. We are trying to see if we can use Kotlin coroutine to achieve multiple requests per thread model in Spring boot. We use CoroutineCrudRepository for the data layer and use suspend functions in the controller and service layers so the application is fully running with coroutines. Still I feel there might be more configuration changes to be done for server layer to make it possible to handle multiple requests from a single thread in spring boot...

How to fix SavedStateProvider with the given key is already registered in fragment In my application I want use this library for ImagePicker : https://github.com/SimformSolutionsPvtLtd/SSImagePicker But after add this line private val imagePicker: ImagePicker = registerImagePicker(this) show me Force close. I want use this into Fragment and this fragment info ViewPager2 . FragmentAdapter code : class FragmentsAdapter (fragmentManager: FragmentManager, lifecycle: Lifecycle) :...

Bigbucket CI/CD : Android Gradle plugin requires Java 11 to run. You are currently using Java 1.8 I am using Bitbucket CI/CD Pipelines to make a Release build of my Android Application. Here I am facing an issue while creating Android Release build. It says An exception occurred applying plugin request [id: 'com.android.application']

Failed to apply plugin 'com.android.internal.application'.

> Android Gradle plugin requires Java 11 to run. You are currently using Java 1.8. You can try some of the following options: - changing the IDE settings. - changing the...

How i can delete firestore listener? I set the listener if isNeedToListen = true, otherwise I remove it, but it still works and I have set listeners that contradict each other when I enter the same chat room from different accounts override fun listenMessage( receiver_id: String, user_id: String, messages: MutableLiveData, onSuccess: (ArrayList) -> Unit, isNeedToListen:Boolean ) { var listenUserMessage: ListenerRegistration? = null var listenReceiverMessage: ListenerRegistration? = null...

Kotlin Nested JSON Array In my Kotlin android app, I need a JSON string. Using the below code i get the below format, [{"Id":"1220w0f9198","status":"Success"}] But i need it in the nested format, like.. { "Setting": [{"Id":"1220w0f9198","status":"Movies"}] } How can i acheive this.. Pls help @Parcelize data class Dataclass1 ( @SerializedName("Id") var Id: String? = null, @SerializedName("status") var status: String? = null ) : Parcelable fun setdataJson() { var genreName =...

How to display interaction element with order way of list one in Kotlin I have two list i want to return in such that list one should match list two and output should i same order as per first list Input : Val first = listOf(1, 2, 3, 4, 5,7,9,15,11) Val second = listOf(2, 15 , 4,3, 11) Output: Val output = listOf(2,4,15,11) Please help me with how to get common value in both list in order of list first in kotlin .

convert List&lt;T&gt; to remember { mutableStateListOf&lt;T&gt;() } data class CartMeal ( val id: String = "", val userId: String = "", val meal: Meal? = null, val count: Int = 0 ) data class CartMealListState( val isLoading: Boolean = false, val meals: List = emptyList(), val error: String = "" ) @SuppressLint("UnrememberedMutableState") @ExperimentalUnitApi @ExperimentalMaterialApi @Composable fun OrderList( state: CartMealListState ) { val orders = remember { mutableStateListOf() } orders.addAll(state.meals) LazyColumn(...