Combine queries in Firestore Currently I am working on a running tracker app for Android phones. For this I will make a follower part also and a news feed. My question is, is there any possibility the combine queries? First I have to check the followed people by the currently logged in user, after that I have to check the time of there last training and order it by descending. So what I need is a list about the followed people what is ordered by there last training. Can I do it with one combined query?

How to create Popup Menu in Context Menu? I want to create a pop menu for context menu, so that when I long press the context menu, it shows another pop up menu. This is the code I've written for context menu override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val button = findViewById(R.id.btn) registerForContextMenu(button) } override fun onCreateContextMenu(menu: ContextMenu?, v: View?, menuInfo: ContextMenu.ContextMenuInfo?) {...

Do sub-type objects going into a data structure become that data structure's declared type? Do sub-type objects going into a data structure become that data structure's declared type? For example, if I put dog objects into a list of mammals, does the objects' type change? open class Mammal(str: String) class Dog : Mammal("") val d : Dog = Dog() var listOfMammal: MutableList = mutableListOf() listOfMammal.add(d)

BleGattCharacteristicException: GATT exception status 129 when trying to Indicate->write->notify to BLE glucometer I am trying to read all the records stored in a glucometer using rxAndroidBle library. According to several resources that I have found the process consist of three main steps after pairing/bonding and connecting to the device: 1.Setup indications in the Record Access Control Point characteristic (RACP) 2.Setup notifications on the Glucose measurement characteristic 3.Write on the RACP characteristic two bytes 0x01, 0x01. Then the notifications should flow if there are any records. Now,...

Kotlin : how to Convert String with ascii code to String without ascii code I am trying to convert all ASCII Codes in a string. I want to convert a String like "Let's find" to "Let's find"in Kotlin i tested these but not worked: str.toByteArray().toString(Charsets.UTF_8) str.replace("'" , "\'")

Swipe left only one time at a time in Recyclerview How can I close already swiped itemview when we swipe a new Item? I tried calling adapter?.notifyItemChanged(viewHolder.adapterPosition) under onSwipe method but didn't help.

Is there a need to suspend DiffUtilCallBack using coroutines when it is used to search or filter a list? fun updateItems( newItems: List?, itemSame: (T, T) -> Boolean, contentSame: (T, T) -> Boolean ) { val diffResult = DiffUtil.calculateDiff(DiffCalc(this.items, newItems!!, itemSame, contentSame)) diffResult.dispatchUpdatesTo(this) items = newItems } Is it a good practice to suspend this using coroutines?

How do I send current location data to another activity? (Kotlin) all good friends? I need to send the current location data to another Activity. How do I send current location data to another activity? And to get this data in another Activity you have to use "getStringExtra" I can get the data from the current location, but I can't send it to another activity. Could you help me, please? class MainActivity : AppCompatActivity(), OnMapReadyCallback, GoogleMap.OnMarkerClickListener { override fun onMarkerClick(p0: Marker?) = false private...

How to test in-app update API in android? I want to integrate flexible updates in my app. Here is my code: fun checkForUpdates(){ val appUpdateManager = AppUpdateManagerFactory.create(this) val appUpdateInfoTask = appUpdateManager.appUpdateInfo val listener = InstallStateUpdatedListener { if (it.installStatus() == InstallStatus.DOWNLOADED){ val snackBar = Snackbar.make(parentLayout, "An update has just been downloaded.", Snackbar.LENGTH_INDEFINITE) snackBar.duration = 10000...

How to get url from okhttp3.ResponseBody? I use Retrofit 2 in my project. I need to handle the errors of parsing and log the request URL in case of an error. I want to do everything in one place. So I made a wrapper for parsing at the retrofit level. Factory: import okhttp3.RequestBody import okhttp3.ResponseBody import retrofit2.Converter import retrofit2.Retrofit import retrofit2.converter.gson.GsonConverterFactory import java.lang.reflect.Type import javax.inject.Inject class LogGsonConverterFactory @Inject constructor(private...

Reading a double does not get the saved value [duplicate] This question already has an answer here: Is floating point math broken? 30 answers assume the variable d below is a double d = 1564036471181.52220 d2 = d - (long)d // returns 0.522216796875 Why does the above not return 0.5222

How to send value in an other activity? Hello and sorry for my english i'm french. I'm learning Android development and i try to send int value in an other activity. I have declared an int variable to 0 and when i press a button the variable go to 1 on other value for each buttons. I know how to create an intent but how can i make it get the value of my button. Thanks.

Retrieve data from raw image taken with camera2API I have used the official sample for using the Camera2 API to capture a RAW sensor frame. The code is in java but I transformed it to Kotlin with the help of Android Studio. I tested it, and I'm capable of taking and saving a dng picture to my phone. Not a problem so far. But what I really want is to be able to retrieve some information about the picture, I don't care about saving it. I want to do the...

Kotlin: Symbol is declared in module 'jdk.internal.opt' which does not export package 'jdk.internal.joptsimple.internal' My enthusiasm to use Strings.isNullOrEmpty in Kotlin 1.2 importing jdk.internal.joptsimple.internal.Strings.isNullOrEmpty has been broken with Kotlin throwing the exception in the title. (Tested with the latest versions of JDK11 and JDK12 - at the date of this post - both of which I suspect are buggy) My main.kt file import jdk.internal.joptsimple.internal.Strings.isNullOrEmpty fun main() { print("Enter your name : ") val userName = readLine()!! if (isNullOrEmpty(userName)) {...

The best way to repeat the request in Project reactor I am quite new in reactive programming. We have an application in SpringBoot using project-reactor. Inside this we make an HTTP request to a third party service and get a Mono as a result. fun getResultFromService() : Mono { //requesting the third party REST API } I would like to: 1. check the response code 2. for some values repeat a request M times with N seconds difference between them What is the best way to do it? what should I use instead of Thread.sleep() I checked...

Spring + Kotlin - Is it possible to detect certain functions calls? I've just started using Spring and Kotlin and wanted to ask is it possible for my app to detect certain function calls? For example, say I have: fun getSuccessMessage() : String { return "great" } Then in my app runner I call that: @Component class AppRunner: CommandLineRunner { @Throws(Exception::class) override fun run(vararg args: String) { getSuccessMessage() } } Can I have another function thats listening and acts whenever its called: fun...

How to handle multiple clicks Before asking, i did search, without success for me. I have some trouble about trying to handle multiple clicks on buttons in my android app. The problem is that when spamming button, i navigate to an other fragment. So spamming button causing navigation crash. I tried a couple of solution, but no one of them that i found was working for me. I tried to : - disable the button - handle with a state (boolean) Actualy, i have navigation crash "blblbl is unknow to this navController" I...

Difference between this two Binders with Dagger2 I have two Binder classes in my project and in one I'm mapping the activities like this: @Binds @IntoMap @ViewModelKey(MainViewModel::class) abstract fun bindsMainViewModel(viewModel: ViewModel): ViewModel and in the other like this: @Binds @IntoMap @ActivityKey(MainActivity.class) abstract AndroidInjector.Factory

IntelliJ and module dependency using intellij, with 2 modules myProject and myProject2. the class First in my Project cannot seen from myProject2, //in myProject class First(){ } fun main(){ } //in myProject2 class Second(){ fun myFun(){ val c = First() } } why intillij cannot give the option [Add dependency on module myProject to let the class First working]

Check if internet is available (targetSdk: Android Q) I wish to implement a simple method isInternetAvailable in my project, which returns either true or false based on whether the internet (any network) is available right at the moment of this call. Unfortunately getActiveNetworkInfo is deprecated since 21 and getActiveNetwork requires minimum API level 23 (mine is 21). I already read about NetworkCallback, but this seems to notify on network changes, I need a method to tell whether the network is available right now or not.

This variable must either have a type annotation or be initialzied. Make a Toast only on startup (Kotlin in Android Studio) I want to make a toast message only ONCE when user enters given activity. I wrote this short piece of code but there is this syntax error 'This variable must either have a type annotation or be initialzied.' var pass = -1 if (pass < 0) { Toast.makeText(this, "Loading Profiles...", Toast.LENGTH_SHORT).show() var pass += 1 }

Not able to reassign value to function parameter val cannot be reassigned I am trying to write a function in kotlin but I am not able reassign value to function parameters ,its saying val cannot be reassigned . class WebView{ var homepage = "https://example.com" fun webViewLoad(url: String, preferredOrientation: String) { if (url.equals("homepage")){ url = homepage } } } when I am trying to assign a value to url = homepage .it is giving me error val cannot be reassigned , I am new to kotlin ,I...

How do I add a lint quickfix to "fix in whole project" for Java/Kotlin? I am able to write a lint warning/error with a QuickFix to change some code in the IDE. I also know that I can tag a Kotlin function with the @Deprecated tag, like so: @Deprecated( level = DeprecationLevel.ERROR, message = "This is wrong", replaceWith = ReplaceWith("doRight(input)") ) fun doWrong(input: String) {} This generates a lint quickfix (LintFix) to replace the function. But it also generates a lint quickfix to replace the function in your entire project, like so: <a...

Constructor injection in data class I'm trying the following: @Configuration @ConfigurationProperties(prefix = "my") data class MyValueConfig( @Value("\${my.value1}") var value1: Int? = null, @Value("\${my.value2}") var value2: String? = null, @Value("\${my.value3}") var value3: String? = null ) Spring does not wire the value fields. My assumption is that the nullable types are providing a "default" constructor. But how should Spring call the constructor to inject the actual values? Is it even possible to have...

'getView' overrides nothing I am new about android studio. I tried to use ArrayAdapter. But when i complete my codes, it says "'getView' overrides nothing".this is my arrayadapter class: class BurcArrayAdapter( var gelencontext: Context, resource: Int, textViewResourceId: Int, var burcAdlari: Array, var burcTarih: Array, var burcResimleri: Array ) : ArrayAdapter(gelencontext, resource, textViewResourceId, burcAdlari) { override fun getView(position: Int, convertView: View?, parent: ViewGroup?): View? { var...

Android Create Table with different borders colors for table and cells Need to create a table of TextViews with Kotlin, with different borders colors for the cells and for the table, something similar to this: I tried using TableLayout and TableRow and use different background colors for cells and table, but now I need the colors between the cells o be different. How can this be Achieved?

Send an email with html format I'm trying to send an intent to Gmail with an HTML code or with formatted text and an image in the body of the email, but I couldn't find a way how to do it. I tried sending an spannableString and using Html.fromHtml

How to get a nested object in JSON in Kotlin? I've created the classes of Eqs and Service, got the service objects but can't get the list of eqs. Can anyone help me with this? This the Eqs class data class Eqs( val name: String, val imageUrl: String, val description: String?, val responsible: String ) That's the Service class which gets its values data class Service( val title: String, val servings: Int, val eqs: List ) { companion object { fun getServicesFromFile(filename: String, context: Context):...

android onClick on include view won't let binding i have a separate layout that i wan't to call click and update a field on callback but it give binding error saying Cannot find the setter for attribute 'android:onClick' with parameter type lambda on com.X.databinding.ItemBinding. but i can binding on other views

MutableList&lt;Int?&gt; и mutableList&lt;Int&gt; I have a homework question: Write the code that compiles fine but throws an exception after you assign a value of type MutableList into a variable of type MutableList. That's how I see it: On cast(get) throws null and this can work with MutableList If we change to we have null exception. I can't understand this task. InteliJ IDEA stops running this compilation every time .