kotlin can't connection to mysql this is my code package com.example.mysql_connect import android.util.Log import java.sql.Connection import java.sql.DriverManager import java.sql.SQLException object Test{ @JvmStatic fun connectiom(){ val cn:Connection var studentScore: Float println("into") try { Class.forName("com.mysql.cj.jdbc.Driver"); Log.v("DB", "OK") } catch (e: ClassNotFoundException) { Log.e("DB", "error") return...

Why doesn't App crash when I use collect a flow from the UI directly from launch in Jetpack Compose? I have read the article. I know the following content just like Image B. Warning: Never collect a flow from the UI directly from launch or the launchIn extension function if the UI needs to be updated. These functions process events even when the view is not visible. This behavior can lead to app crashes. To avoid that, use the repeatOnLifecycle API as shown above. But the Code...

How to solve foreground service issue in android 12 I am using foreground service for detect the trip in background. Everything is working fine in android 11 and below 11 version. but When i test the app in android 12, then background operations is not performed properly. Service is always destroying in background. how we detect the trip in android 12. Because it is important for trip detection. can anyone suggest me how to solve this problem.

a plugin version that doesn't match the code will there be a problem? I want to install gradle 7.2 into a finished android project (because there is no gradle), but in gradle 7.2 the plugin version must be included, if the version I enter doesn't match the code, will there be a problem? is there a solution so that the project can be installed gradle and run?

This is a toggle able button i did using xml.Is there a method to implement this using jetpack? A toggleable button with the texts in progress and completed.The selected button is yellow and lightgray when not selected . @ views are displayed when the buttons are selected and not selected.

How to switch to "single activity"? | Kotlin I wrote a simple program with two activities. I want to change the second activity to a fragment. How should I do it? Below is the code of the activity that I want to turn into a fragment and switch to a single activity. I want to move to single activity architecture. But i don't know how to create fragment from this. import android.content.Intent import android.os.Bundle import android.widget.Button import android.widget.EditText import android.widget.Toast import...

How to get new variable value from inherited class? open class Parent(){ protected var z : Int? = null private fun getMyAge(){ val x = 65 val y = 10 val z = x % y } } class Child:Parent(){ println(z) //here I get null } My question is: why I get null? Am I getting a variable from an inherited class incorrectly?

Nullable variable throws NullPointerException on get() Here is some mistic error. I have such a code: if (countryCode.value.code != US_CODE){ doSomething() } "If" line throws Error: NullPointerException: Attempt to invoke virtual method 'java.lang.String com.data.models.CountryCodeValue.getCode()' on a null object reference "code" field is nullable, and I don't get why it happens CountryCodeValue model: data class CountryCodeValue( val code: String? = null, val name: String, var description: String )

What are differents between handleMeter.uiState.collectAsState() and remember { handleMeter.uiState } in Kotlin? uiState is MutableStateFlow in ViewModel() , Code A and Code B can update UI automatically based latest value of the flow. 1： What are differents between handleMeter.uiState.collectAsState() and remember { handleMeter.uiState } in Kotlin ? 2：Code C is wrong, I can't wrapped handleMeter.uiState.collectAsState() with remember , why? How can I remember the latest value of the flow? Code A @Composable fun Greeting(handleMeter: HandleMeter,lifecycleScope: LifecycleCoroutineScope) { Column(...

Set background color according to text recycler view Kotlin I've a simple recycler-view which has a list of names. Now what I want to achieve is like if the name starts with A the color should be red and if it starts with B it should be blue and so on. How can I do it?

Convert Observable to Flow UseCase should return Flow from Observable. When i try to use .asFlow() - i get error Unresolved reference: asFlow class GetHistoryUseCase( private val repo: HistoryRepo, backgroundScheduler: Scheduler, postExecutionScheduler: Scheduler ) : UseCase( backgroundScheduler, postExecutionScheduler ) { override fun buildUseCaseObservable( param: Params ): Observable = Observable.just(repo.observe(date = param.date).asFlow()) class Params( val date:...

Micronaut openapi page is blank when using jar file I use micronaut with Kotlin and Gradle with Kotlin DSL. Enabled OpenAPI which works fine when running the application from Intellij. But when starting the JAR, I get a blank page when opening for example: http://localhost:8080/swagger/views/redoc Not a 404 but 200, just a blank page - no content is transferred to the browser. Using this compiler args: kapt { arguments { arg( "micronaut.openapi.views.spec",...

Unable to get DATA from Local Server Created on another machine using Retrofit Kotlin I was using a Fake Api till last day which worked very fine for me. But today i was told to use Local Server created on another machine. The url i was using till yesterday to fetch data was https://my.api.mockaroo.com/products?key=57b501f0 But Now i have to access this : http://192.168.18.59:8000/hot-products/ But I am...

get firebase notification in android and redirect to fragment I want to send the posts shared in my application as notification to users whenever I want. Users should get the post's user ID when they click on the notification. I am posting the retrieved uid to my detail page so I can get the data of the incoming UI in my detail page. I do the process like this, but I don't think it's the right usage. How should it be used correctly?

io.ktor.client.features.ClientRequestException: Client request invalid When calling the getUser function, I make an HTTP request that retrieves information about a user. If the user does not exist I get the error: io.ktor.client.features.ClientRequestException: Client request(https://api.intra.chocolat.fr/v2/users/fff) invalid: 404 Not Found. Text: "{}" I am unable to catch the error, and to continue the execution of the program. package com.ksainthi.swifty.api import...

TextInputLayout exposed dropdown menu suffix problem I'm updating TextInputLayout suffixText programatically. The simple example below is toggling between no suffix (null) and a "long suffix" depending on which option you select from an exposed dropdown menu. The application starts with the "long option" selected and no suffix shown. The problem is that if you select "option 2" the "long suffix" is displayed but then when you go back to the "long option" although the suffix disappears as required the suffix still appears to be occupying space...

Make a api calling application [closed] Which will have 2 textboxes Country Code Mobile Number Add one button "Submit" When user click on "Submit" button you have to call API service and pass 2 fields parameter. You have to show response from that you get from API. response will have total 5 fields so you have to show 5 fields data in 5 different textviews

Load WebExtensions on GeckoView I'm working with GeckoView and met problem with installing AddOns. As suggested on Documentation, I've provided XPI compatible with Android, but nothing changes. Copying file to Assets doesn't make a change. Browser doesn't acknowledge WebExtension. runtime.webExtensionController .install("https://addons.mozilla.org/android/downloads/file/3719055/youtube_high_definition-85.0.0-an+fx.xpi") .accept( { extension: WebExtension? ->...

RecyclerView - Add header based on object field Say I have a RecyclerView and I'm populating it with an object. And the object has a date field, and when a new date is reached, a standalone header is created with that date, and then the item is added. The following objects with the same date will not create a new header, unless it's a new date. Is it possible to do this (maybe using getItemViewType), while also being compatible with ItemTouchHelper? So, if I remove the last item under a header at runtime, it'll also remove the header? Also...

How to handle AWS Secret Manager rotation in a Spring boot project for Kafka consumers with SASL Authentication Strategy I have a spring boot application with the following configuration for Kafka consumers: @EnableKafka @Configuration class KafkaConsumerConfig( @Value("\${aws.secret-manager.sasl-auth.secret-name}") private val kafkaAuthSecretName: String, private val kafkaProperties: KafkaProperties, private val awsSecretManagerAdaptor: AwsSecretManagerAdaptor, private val applicationContext: ApplicationContext ) { private val logger = KotlinLogging.logger { } @Bean fun...

I want to put the button at the center, but i don't know where is the mistake, can you help me? Here what i done

Error: Given final block not properly padded. Such issues can arise if a bad key is used during decryption I am really stuck on this issue while generating a signed apk in android studio v2020.3.1 patch 2: I created a key store path as it was my first time, I added the path, alias, key store password and key password but after the creation when I used it, I got an error while generating the signed apk: A failure occurred while executing com.android.build.gradle.tasks.PackageAndroidArtifact$IncrementalSplitterRunnable com.android.ide.common.signing.KeytoolException: Failed to read key passvault...

Android Convert RXJava 2 Maybe to a coroutine? My project intends to replace RxJava with coroutines. Use RxJava Maybe.concat to access network and database data. First search for the data in the database, if there is no data in the database, download the data from the Internet. If the database has data, the network data will not be downloaded. Is there a way for coroutine to achieve a similar function? And, Is it necessary to use 'kotlinx-coroutines-rx2'? fun getMovieImg(): Flowable { return Maybe.concat(...

Android - Ripple and shadow on view? Is it possible to have a ripple effect on a view at the same time as you have a dropdown shadow? I can't figure it out. Thanks in advance

How to send a notification to the user once at a particular time? The user should receive a notification at a specific date and time, but the notification just comes right away, instead of arriving when needed. How to make sure that the notification comes at the right time, and not immediately? class MyReceiver: BroadcastReceiver() { private var title = "" private var desc = "" override fun onReceive(context: Context?, intent: Intent?) { try { intent?.let { title =...

Difference between launchWhenStarted and repeatOnLifecycle(STARTED) in collecting flows As launchWhenStarted and repeatOnLifecycle(STARTED) provide completely different functionality (launchWhenStarted suspends the execution of the coroutine, and repeatOnLifecycle cancels and restarts a new coroutine), if the names of the new APIs were similar (for example, using launchWhenever for the restarting APIs), developers could’ve got confused and even use them interchangeably without noticing. <a...

How do I perform a network process in a kotlin coroutine I am attempting to run the getByName method in my android app, but have found that doing so in the main activity is cause for concern. I know I need to use coroutines, or async, or threads. But I'm not sure how to go about this. I'm somewhat self-taught with the software so forgive any obvious errors. ''' class MainActivity : AppCompatActivity() { private lateinit var binding: ActivityMainBinding override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState)...

lateinit property binding has not been initialized though i did not set it as lateinit I faced that error when i was trying to update my views with new ViewBinding stuff. I don't define the value as "lateinit" but logccat says "lateinit property binding has not been initialized" why i m taking this ? Thanks in advance. The exception is on private val email and password rows. class MainActivity : AppCompatActivity() { private lateinit var auth : FirebaseAuth private lateinit var binding: ActivityMainBinding private val email = binding.emailText.text.toString() private val...

Specification Left Join with @JoinTable I'm trying to retrive some data using JPA's Specification but this is getting confusing since I have a @JoinTable annotation without a relational entity class. I have those entities: @Entity @Table(name = "tag") data class Tag(@Id @Column val id: UUID, @Column val name: String) and @Entity @Table(name = "post") data class Post( @Id @Column val id: UUID, @Column val title: String, @Column val content: String, //other fields @OneToMany(fetch = FetchType.LAZY, cascade =...

Multiple Options in reyclerview Android Hey I am working on reyclerview android kotlin. I want to create something like this in reyclerview. I am adding screenshot, how my view looks. My json looks like this Drive link In my image there is two view. First view contains strength items and second view contains quantity item. Black box is...