Save activity state Android studio How could i save the activity state and values after closing application and when i open it again it have the values of radio button and spinner and edit text in android studio in kotlin or in java

Error in Appcompat Dependencies when implementing MaterialProgressBar in build.gradle I'm getting an error in my mplementation 'com.android.supportappcompat v728.0.0' at gradle.build file after implementing implementation 'me.zhanghai.android.materialprogressbarlibrary1.6.1' dependencies { implementation fileTree(dir: 'libs', include: ['*.jar']) implementation"org.jetbrains.kotlinkotlin stdlib jdk7$kotlin_version" implementation 'com.android.supportappcompat v728.0.0' implementation 'com.android.support.constraintconstraint layout1.1.3'...

Downloading pdf with okhttp and okio I'm facing some problems downloading pdf inside my app. Some pdfs cannot be opened, because of the following message (invalid format) Error = cannot create document: File not in PDF format or corrupted Code for Okhttp setup: val file = File(Environment .getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS), mArgs.docName) val request = Request.Builder() .url(mArgs.url) .addHeader("Authorization", "Bearer $token") .build() if (mOkBuilder == null) { mOkBuilder =...

Cannot call suspend function from launch Im new to kotlin coroutines and I'm trying to call a suspend function from oncreate using launch. But the code would not execute. launch { callSomeApi() } suspend fun callSomeApi() { withContext(Dispatcher.IO) { //perform network call } } It says suspend function should only be called from a coroutine or other suspend function. Although Im calling it from launch. Please let me know what am I doing wrong?

Spring Boot File not Found [duplicate] This question already has an answer here: Classpath resource not found when running as jar 8 answers My Code: val csvFile = this::class.java.getResource("/static/sampledata.csv").file if I run it from the ide, everything works fine. But if I build the app, I get:...

Allow Android app to connect to site with self-signed SSL certificate (Trust anchor for certification path not found) I'm setting up an app to connect to and retrieve data from a custom backend using Retrofit2 and RxKotlin2/RxJava2. It's my first time using both Retrofit and RxJava. I've already tried using just http:// instead of https://, this just results in the app timing out and not connecting with a java.net.SocketTimeoutException. Here's my Retrofit client: val requestInterface = Retrofit.Builder() .baseUrl("${BASE_URL}") .addConverterFactory(GsonConverterFactory.create())...

TextView not showing up when I add it to LinearLayout I try to create a cardView that contains an image and beside that image I want to add two lines of text (vertically stacked on each other). Below is the code I have written to do this (the function returns a cardView). However, in my cardView nothing is appearing. If I remove the linearLayout and the textViews than I get a card which shows the imageView. So I assume I'm doing something wrong with the way I set the linearLayout on my textViews or the way I add my linearLayout to my tableRow....

Error: Kotlin: The floating-point literal does not conform to the expected type Float I was making a simple maths calculator in kotlin, an error appeared on my screen when I tried to initialize the value of one of the variables used as 0.00 for float integer. var x:Float= readLine()!!.toFloat() var y:Float= readLine()!!.toFloat() var sum:Float=0.00// the error message is showcased in this line sum=x+y println("Addition " + sum)

Conversion of put() in Kotlin I have the following function in java and I need to convert it to Kotlin. @Override public void afterTextChanged(Editable s) { if (s != null && !"".equals(s.toString())) { int position = (Integer) mHolder.numEdit.getTag(); // Saved to the data variable when the data changes mData.get(position).put("list_item_inputvalue", s.toString()); } } So in this way I do not...

How to use recyclerview-selection by setting the key as a string? Using the android library androidx.recyclerview.selection, I have tried to implement multiple selection in RecyclerView following the tutorials here and here. But, I want my key to be a String, instead of Long, but I am facing two errors as...

How to configure google app engine on gradle IntelliJ Kotlin "JS Client and JVM Server" project? I would like to create a Kotlin project where the client site is JS and the server side is a Google App Engine standard enviroment application. On IntelliJ, exist a New Project Kotlin option called "JS Client and JVM Server | Gradle". This project creates this build.gradle: buildscript { repositories { jcenter() } } plugins { id 'org.jetbrains.kotlin.multiplatform' version '1.3.40' } repositories { jcenter() maven { url "https://dl.bintray.com/kotlin/ktor" }...

Optimize Dependency Tree Calculation. - Kotlin following snippet sorts a list of Table based on its dependencies upon each other. Table(s) with no dependencies should come first followed by Table(s) which depends on its preceders. data class Table( var name: String = "", var dependencies: ArrayList = ArrayList(), var dependencyTree: ArrayList = ArrayList(), var syncOrder: Int = -1 ) : Comparable { override fun compareTo(other: Table): Int { val thisHasNoDependencies = this.dependencyTree.isEmpty()...

Unsolved reference: AmazonDynamoDBClientBuilder I am trying to add DynamoDB to my Kotlin + Gradle project. However, when I want to use: val builder = AmazonDynamoDBClientBuilder.standard() I get Unsolved reference: AmazonDynamoDBClientBuilder. However, I can reference AmazonDynamoDB, AmazonDynamoDBClient, AmazonDynamoDBAsync and AmazonDynamoDBAsyncClient. I use Gradle 4.10.1, so I followed the second section of the <a href="https://docs.aws.amazon.com/sdk-for-java/v1/developer-guide/setup-project-gradle.html" rel="nofollow...

Refer to own type in Kotlin object member I have some objects like so: interface Maker interface Thing I want Thing to hold a reference to its Maker, but I can't figure out how: interface Thing { val maker: Maker // ?? } so that I can have something like: class BallMaker : Maker object Ball : Thing { override val maker = BallMaker } How can I achieve this?

How to update cursor inside MainActivity from RecyclerViewHElper class I have MainActivy class and inside of it I have cursor (I get it from SQL database). I use this cursor to make RecyclerView inside of MainActivity: recyclerViewOfLists = RecyclerViewHelper(cursor, this) When user presses on reciclerView itemView he can delete that item (code below is inside of RecyclerViewHelper) itemView.delete.setOnClickListener { deleteItemFromRecycler(position) } fun deleteItemFromRecycler(position: Int){ val db = DataBaseHelper(context)...

Type erasure on Map.minus(Map) result key Sample code: val map1: Map = ... val map2: Map = ... val result = map1 - map2 The type of result is indicated as Map in Android Studio, forcing me to resort to: val result = (map1 - map2).mapKeys { it.key.toString() } Documentation leads me to expect preservation of type K, or am I missing something here? /** * Returns a map containing all entries of the original map except those entries * the keys of which are contained in the given [keys] collection. * * The returned map...

how to remove previous result list immediately when updating recycler view? here is the short video of my problem: https://drive.google.com/file/d/108Tk9rmJtF3Ir7Nj9hheW2JkvlqXggcj/view so, I have a vertical recycler view that can be refreshed when the tab layout is tapped. If I tap the first index of the tab, it will fetch some data from the server and populate the adapter and recycler view. but if I tap the second index, the data from server is actually...

Kotlin String replace including delimiter I have a common pattern where I want to operate on a string like abckey123 where I want to clear the string before key but also remove the key. Is there a commonly accepted way to do this? Or even better a way to make this a single method call on all string objects? Ideas: item.replaceBefore("key", "").replace("key", "") item.split("key").last()

Best way to associate an entity JPA I have a manytoone relationship between two entities and i want to know if there's a better option to save using an existing id, for example, in the example below, should i send a company id inside json or first create a Role and the using PUT update the Role with company Id. Or maybe inside the Controller find the company entity and then set in the new Role entity and after that, save it. How to proceed in this case? @Entity data class Role( val name: String = "",...

Kotlin Testing Quickstart What is the quickest/easiest/best way to add testing to a Kotlin project? I have more experience in the Python ecosystem where I can use pytest or unittest to find classes and/or functions starting or ending with test_ or _test. Is there an analogous project in the Kotlin ecosystem? I found documentation for <a...

What would be the logic of a function offering the user similar posts before posting a new post? I am creating a sort of forum, and would like to create a function that gives the user suggestions for similar posts before posting a new post, just like in SO. I am not sure how to approach this and create this function in the most efficient way? What the parameter by which I determine what is a similar post? I will do it by the title of the post only, but still not sure what would be the logic behind it and I've been thinking about it for quite a while now. Also, I am working with cloud...

What native search engine can be used for my use case? I am working on an android application where some secured data will be stored in android device and frequently be queried from web app side. Right now I am storing the data in SQLite DB. When the application is opening I am loading the full data from DB and preparing a filter map for efficient in memory queries for web app. However, for large amount of data in-memory query might not be a scalable solution. I want to apply if there is well known data query framework or library in my...

Passing arguments between Fragments that are inside a ViewPager This gonna be a little long describing the issue, but I'm trying to be specific to describe it well, thanks for your time! So, I'm working with different Fragments that are hosted by a ViewPager. The main purpose of doing this is because I need to convert a paper form into a digital form, and for user-friendly purposes, I decided to let the user swipe between all the fragments and complete each of them until the end of the form. My goal is to construct an object at the end of the latest...

Android - Firestore returns an empty query using startAfter() and limit() I'm trying to implement a pagination system using Firebase Firestore startAfter() and limit() query methods. The first query is returned successfully, but the second one returns an empty snapshot. Here's my getNextPage() method : fun getNextPage(paginationSize : Long) : TrendingRepository { database.collection("app") .document("data") .collection("offers") .orderBy("discount") .startAfter(lastVisible) .limit(paginationSize) .get().addOnSuccessListener { snapshot ->...

How to set and clear error message for textinputlayout in Android databinding viewmodel I want to set an error message and clear error message for textinputlayout edittext using viewmodel architecture in kotlin

A fragment with 2 tabs without viewpager I have an app with a navigation drawer with fragments. Now I want that one fragment has 2 tabs inside of it with each tab another fragment. I search several days for an example but didn't find one in Kotlin Code. It is always an activity with tabs with fragments but never a fragment with 2 tabs en each a fragment. Who can help me to start? Searching for an example en this for weeks. Mainactivity.kt class MainActivity : AppCompatActivity(), NavigationView.OnNavigationItemSelectedListener {...

How to convert GMT +09:00 to local time? When I print date, it shows Mon Jun 24 161531 GMT+09:00 2019 val formatter = SimpleDateFormat("yyyy-MM-dd HHmmss") val date: Date? = formatter.parse(checkedDate) val transformedDate = ("${String.format("%02d", date!!.month + 1)}.${String.format("%02d", date!!.date)}.${date.year + 1900}") val title: String? = ("$transformedDate") val longGmtTime = date.time val mZone = TimeZone.getDefault() val offset = mZone.getOffset(longGmtTime)...

How to use indexOf in kotlin for ArrayList of a data class? In kotlin, I have a data class like this: data class MyModel ( val key: String, val myValue: String ) I have an ArrayList of above model: val myList: ArrayList I don't know how to get the index of an element by passing the key: fun getPosition(key: String): Int = myList.indexOf(/* what to do here? */)

How to use Ktor BoundDatagramSocket to listen to incoming udp traffic I'm using ktor for a kotlin/native app. Currently I'm testing things out on the android side and because of that I have some code directly in the viewmodel. The app needs to listen to incoming udp datagrams but it doesn't seem to receive anything. What am I doing wrong in my implementation? How I listen to the incoming data while testing: viewModelScope.launch(Dispatchers.IO) { aSocket(ActorSelectorManager(Dispatchers.IO)).udp()...

simulate keyboard keys in app inventor or thunkable or kodular like app building websites i want to somehow simulate ctrl+a and ctrl+c in my app inventor app, but how do i do so, i want to copy the whole elements(not the source code, because the web page only has elements and source codes shows nothing) of a web viewer using this method for checking a particular text/string in a web-page. bottom line is i want to simulate a keypress without pressing the key in my app. tried activity starter but there are so less examples of it. app-inventor is based on blocks but still some...