Firestore error Could not deserialize object I am trying to make a kotlin application. I am getting error like this: java.lang.RuntimeException: Could not deserialize object. Class com.manager.mymanager.models.Task does not define a no-argument constructor. If you are using ProGuard, make sure these constructors are not stripped (found in field 'taskList.[0]') The function where it is pointing the error is: fun getBoardsList(activity: MainActivity){ mFireStore.collection(Constants.BOARDS)...

Device dimensions in Kotlin not java How do i calculate the dimensions of a device in kotlin android studio? I have tried: val displayMetrics = DisplayMetrics() windowManager.defaultDisplay.getMetrics(displayMetrics) var width = displayMetrics.widthPixels var height = displayMetrics.heightPixels It gives me following error: "getter for defaultDisplay: Display!' is deprecated. Deprecated in Java:" Thank you

How to achieve custom back navigation from fragment using activity toolbar up button? given using navigation component toolbar and navigation drawer val drawerLayout: DrawerLayout = findViewById(R.id.drawer_layout) val navView: NavigationView = findViewById(R.id.nav_view) val navController = findNavController(R.id.nav_host_fragment) appBarConfiguration = AppBarConfiguration( navController.graph, drawerLayout ) NavigationUI.setupWithNavController( toolbar, navController, appBarConfiguration ) setupActionBarWithNavController(navController, appBarConfiguration)...

Reading, Comparing and returning values from firebase for android app So i have data stored in the firebase realtime database in a way as represented below [ { "Course": "bcom", "a": 1, "b": 11, "c": 13 }, { "Course": "bsc", "a": 2, "b": 22, "c": 5 } ] here i want the user to first enter the course they want to pick. For example if they chose bcom, i then want them to enter a percentage which is right next to the colleges titled a b c. and if they are greater than or equal to the number next to the collegenames for a...

How can I code buttons to change layouts in Kotlin? I am trying to make a text-based choice game for Android, very similar to the game called "Magium" https://play.google.com/store/apps/details?id=com.magiumgames.magium&hl=en Users will choose from a few options by pressing respective buttons to progress the story. After a buttons press, I want the app to show another layout. Let's say there is only one button (named button1) in...

How to extract specific text from webpage using Kotlin? I am working on an Android app using Kotlin. I want to extra the paragraph under Movie Info in this link https://www.rottentomatoes.com/m/john_wick_chapter_3_parabellum I can see the content is in the div tag with id=movieSynopsis. How can I extract this text using Kotlin? Thank you!

How to check which item is visible on screen of recyclerview I want to know the visible item on screen so that if the exoplayer of that item is running I can stop it. Here I have tried many ways to stop already running exoplayer but I've not found any appropriate solution. Can anyone tell me how can I achieve this. Using all these four methods is not giving me visible items of recyclerview. It's only giving me the last item and the first item visible on the screen as their name suggests rvTips.addOnScrollListener(object :...

Pass string from onLoadFinished method to another activity I have created a content retriever which calls data from the content provider in another application, I can read the data successfully, but I want to pass the data from the onLoadFinished Method in my content retriever to an activity which should display the data on button press. But I am unsure of how to do it, I tried using a getter and setter, but it does not print anything. Here are the rows in my content provider: String[] columns = new String[]{"_id", "item"}; MatrixCursor matrixCursor...

NonNull MutableList throws NullPointerException I'm facing a strange issue where a NonNull MutableList throws a java.lang.NullPointerException. Below is what my code looks like: private var events: MutableList = mutableListOf() fun onCallback(e:String) { events.add(e) //NullPointerEception here } fun otherCallback(){ events = mutableListOf() } Nowhere I'm assigning null to the list. (It wouldn't be possible to do so anyway) but I'm suspecting that at some point during the concurrency the list becomes null, just before re-initializing...

Call requires API level 26 while using Java 8+ API desugaring support I'm testing Java 8+ API desugaring support on a project with minSdk 23. When I use the java.time library, for example val instant = Instant.now(), I get the following error: Call requires API level 26 (current min is 23): java.time.Instant#now The code compiles and executes correctly. Can I assume it will work for all devices?

How to check if a file has existed or not form android Q and above using Kotlin I used this code before and now this code is not working because of android 10 update val direct = File(Environment.getExternalStorageDirectory().toString() + path + title) return direct.exists()

What's the difference between sumOf() and sumBy() in Kotlin 1.4? How is the new sumOf() function in Kotlin 1.4 different from sumBy() or sumByDouble() functions?

How can I scroll to a specific location in Scroll View via Kotlin? I am brand new to Kotlin/App Development {2 weeks}. Currently I have a Scroll View and I would like to go to specific locations within the scroll view. One of my issues is I can't seem to find much Kotlin code on here. I've tried to convert the Java but not having much success. I'm also not sure where to put the code that I have indeed found. This is what I have so far: class AKCell : AppCompatActivity() { public fun civilClick(view: View) { val ascrollView =...

Why min() and max() collection methods are being deprecated in Kotlin 1.4? It seems that min() and max() methods are being deprecated in favor of minOrNull() and maxOrNull() functions. What's the reason for this?

How to save information to LevelDB and then process this information in another route? I want to save information being processed to a level DB, right now what I have is from(sourceUri) .transacted() .unmarshal().json(JsonLibrary.Jackson, HashMap::class.java) .log(LoggingLevel.INFO, "input ${body}") .end() So what do i put there to save the data incoming into a levelDB? I dont want to use aggregator as it doesn't fit what im doing so at the moment I need to save it into the...

Parsing CSS data in Kotlin I'm working on my mobile app now and I trying to create home fragment in navigator bar which show me news from one site. For now I created a function that parsing html data with Jsoup and it already returns me title , subTitle and image ref. But also I need to know the style of that texts. Bold it , italic or which color is it. I found this question on stackoverflow question and maybe you know some...

How access another fragment from a fragment in Android using Kotlin? val dialog = AlertDialog.Builder(activity as Context) dialog.setTitle("Confirmation") dialog.setMessage("Are you sure you want to log out?") dialog.setPositiveButton("YES"){ text, listener -> sharedPreferences.edit().clear().apply() println("Shared preferences cleared") println("Logged out") val intent = Intent(activity as Context, LoginActivity::class.java) startActivity(intent) } dialog.setNegativeButton("NO"){text,listener ->...

how can i make a layout skip the notch I want to create a funtion so it recieves a ConstraintLayout, and make it skip the notch on the top. private fun ajustarLayout(layout: ConstraintLayout ){ operations on "layout" so have a space from top and skip the notch } Also is possible to know if the actual device has in its hardware notch, in case that is it, make two versions of the activities one for notch device and other for non notch devices

Kotlin + Spring Boot + @Valid not worked child object's internal object Here's the code: data class Father( @Valid val sonExamResult: Son.ExamResult ) data class Son( val examResult:ExamResult ){ data class ExamResult( @field: Size(min = 0, max = 100) val math:Int, @field: Size(min = 0, max = 100) val physicalEducation:Int ) } How can I verify a data structure similar to the above? I try to pass a -1 to ExamResult.math, but nothing happend. My native language is not English, I am...

java.lang.IllegalArgumentException: onRestoreInstanceState I have an app published at google play and I receive this error many times from my users. But I don't know how to solve it, because the trace doesn't tell me where the error is in the code, so I don't know where to look. Any sugestions? java.lang.IllegalArgumentException: at android.view.View.onRestoreInstanceState (View.java:21606) at android.view.View.dispatchRestoreInstanceState (View.java:21578) at android.view.ViewGroup.dispatchRestoreInstanceState (ViewGroup.java:4693) at...

How to read and write SharedPreferences when use "androidx.preference:preference-ktx:1.1.1" with Kotlin? Normally, I use Code A or Code B to read or write SharedPreferences. At present, I update my project to use "androidx.preferencepreference ktx1.1.1" with Kotlin. Is there a better way to read and write SharedPreferences when I use "androidx.preferencepreference ktx1.1.1" with Kotlin ? Code A SharedPreferences prfs = getSharedPreferences("AUTHENTICATION_FILE_NAME", Context.MODE_PRIVATE); String Astatus = prfs.getString("Authentication_Status", ""); Code B SharedPreferences preferences =...

How to perform an async task for every item in a for loop? I have a list of urls in a mutable list and I want to perform an IO operation, cacheVideo on each of the urls sequentially one after the other suspend fun cacheVideo(mediaItem: MediaItem) = { val videoUrl = mediaItem.mediaUrl val uri = Uri.parse(videoUrl) val dataSpec = DataSpec(uri) val progressListener = CacheUtil.ProgressListener { requestLength, bytesCached, newBytesCached -> val downloadPercentage: Double = (bytesCached * 100.0 /...

Fragment transaction sometimes throwing exception This part of code inside an androidx.fragment is throwing a few daily Exceptions, I have been investigating a lot but I cannot find the problem. private fun addRatingWidget(ratingItem: RatingItemEntity) { val context = context if (context != null) { ratingContainer?.removeAllViews() ratingContainer?.visibility = View.VISIBLE val promptLayout = RelativeLayout(context) promptLayout.id = ViewCompat.generateViewId() val...

Best approach for creating message notifications to user independent of app status (Active, Paused, Stopped and Destroyed) I wish to develop my (kotlin) app so that my user receives message notifications at all times whatever the app state. I would really appreciate a pointer or two in the right direction. I need constant network access to be able to query my remote database. Thanks in advance. Chris

Add iterator to id --> R.id.+i+ i have 8 checkboxes and i want to know which ones are enabled when button clicked. So first i tried the method below. Checkbox ids: c1, c2, c3... saveBtn.setOnClickListener { for(i in 1..8){ var tempId = "R.id.c"+i+"" if(findViewById(tempId.toInt()).isEnabled){ } } } And i got the error: FATAL EXCEPTION: main java.lang.NumberFormatException: For input string: "R.id.c1" I realized that toInt() method is useless cause...

Kotlin detect linter: how to include detektTest into detect gradle step? The question is about io.gitlab.arturbosch.detekt linter for Kotlin. I also use gradle in kts format. By default "detektMain" step includes into "detect" step, "detect" step includes into "check" gradle step. My goal is finally to include "detektTest" into "check".

Time limited firbase users How to make Time Limited Users with countdown after count down finished then firbase users account get deleted or disabled automatically is this possible in java or kotlin Please help me and share me code if u know

Using Spring Data Specifications, how do you compare a division of two columns with some input value? I'm having trouble writing Spring Data Specification which is supposed to filter out some rows out of DB search query. Suppose there is a table in a database. This table contains two columns both of which have int type. I need a Spring Data Specification which would filter by division of those two columns. So if those columns are A and B, then a need to compare A/B with some known input value. Here is what I'm trying to do (I'm using Kotlin) return Specification { root: Root, _:...

MaterialAutoCompleteTextView IndexOutOfBound when recreating activity I have implemented a MaterialAutoCompleteTextView styled as an ExposedDropdownMenu to allow users to change the language in-app, but I'm experiencing an IndexOutOfBoundException on some devices after selecting the desired language. Basically I have a settings fragment in the MainActivity where there's this "spinner" from which the user can select the language (available languages are fetch from a string-array in strings.xml). When this happens the ApplicationClass applies the new...

Can any one please tell us about facebook comment dialog like scrollable animaiton [closed] I need to make this type of animation as shown in image ,Please help.