kotlinlang #android

Hi all, does anyone have any data you can share on the size impact of converting JVM/Android libraries from Java to Kotlin? Working with a library team that is looking for good benchmarks on this.

Zac Sweers

05/06/2020, 5:35 AM

@ channel isn’t a thing in slack. You also should not be trying to @ channel a channel with 26,000 members

➕ 3

🤣 2

Apex

05/06/2020, 7:31 AM

How are the new swipe gestures in slack beta implemented ? If anyone could point to relevant documentation or example , it would be really great

🤔 1

Nikola Milovic

05/06/2020, 5:56 PM

Any way to debug release build via attaching debugger? My app works in debug build but doesn't work in release (without changing the code). I can't pinpoint the problem as there are no errors. I just need to add breaks in release build somehow

iex

05/06/2020, 8:19 PM

Hi! Please help with mocking in Unit Tests... I've a global logger class (I know this isn't ideal, but for now it's convenient) that wraps the Android logger. I'm now running unit tests and it crashes with "Method i in android.util.Log not mocked". So I need to mock this class somehow. Can I do that, given that it's in a global

val

Marcin Wisniowski

05/07/2020, 5:04 PM

Hello, I'm trying to build a single activity app with the navigation library. My fragments load some data from the network in their `ViewModel`s. I want to show a loading screen when data is loading, without creating a loading screen in every fragment, so I want to have a loading screen layout in the main activity layout. But how do I communicate the loading state to the Activity? If the loading screen was in the Fragment, I could just have a

LiveData

with the loading state and toggle the loading screen based on that. But if the loading screen is in the Activity, I have no access to the Fragment's

ViewModel

. What am I missing?

Vishvendu

05/07/2020, 5:37 PM

https://stackoverflow.com/questions/61660857/pass-data-from-fragment-with-recyclerview-to-the-other-fragment-using-viewmodel

Nikola Milovic

05/07/2020, 5:42 PM

Anyone had weird experiences with minifyEnabled shrinkResources My release build doesn't work (room database problems) when minify and shrink are enabled, but works when they are disabled. I've never noticed this for a long time, baffles me how can this affect the apps work. Edit: By not work i literally mean unusable app. I save some data into the database and then need it for later use, the data is null if the minify and shrink are enabled in release build, and it works fine if they're false. I seriously don't know what's happening The app is relatively small, should i just disable them all together?

lawlorslaw

05/07/2020, 8:05 PM

How do you write a junit test for this function? The part that fails is the call to

file.sink()

because it throws a

FileNotFoundException

Untitled

adams2

05/07/2020, 11:01 PM

Hey so I am trying to use the

androidx.lifecycle.observe

ktx extension. When I do

viewModel.observe(this, ::myOnChanged)

, I get this error:

Type mismatch: inferred type is KFunction1<Action, Unit?> but Observer<in Action!> was expected

. However, when I do

viewModel.observe(this) { myOnChanged(it) }

, the extension functions as expected. Is there some precedence rule preventing me from using a method reference?

lawlorslaw

05/08/2020, 4:22 AM

How do you wait for the results from N asynchronous operations?

Joao Birk

05/08/2020, 4:28 PM

Hi there, did anyone use this guy before? https://github.com/android/architecture-components-samples/blob/master/NavigationAdvancedSample/app/src/main/java/com/example/android/navigationadvancedsample/NavigationExtensions.kt Im trying to use it with a custom toolbar per fragment, the back button is not showing up. Did anyone use this with custom toolbar in their fragments successfully?

PenguinDan

05/08/2020, 7:13 PM

Hello, I am currently using Splitties View DSL https://github.com/LouisCAD/Splitties/tree/master/modules/views-dsl and I came across the following issue. • Attempting to start an AlertDialog with a custom size. I can't customize the size of the root layout (since we don't use a parent ViewGroup, aware of how LayoutInflater + Parent + attach to parent works)

override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? = EnsureDialogUi(requireContext()).apply {
        yesButton.setOnClickListener {
            ensureListener?.onYes()
            dismissSafely()
        }

        noButton.setOnClickListener {
            cancelSafely()
        }
    }.root

// My Ui code
...
    override val root: View = constraintLayout {
        // Set the parameters of our ConstraintLayout container
        layoutParams = ConstraintLayout.LayoutParams(
            DeviceUtil.calcDiagRatioInt(0.33f), wrapContent
        )
...

Any ideas how I would go about doing this?

dewildte

05/09/2020, 12:54 AM

It seems to be corrupt on windows.

Joshua

05/09/2020, 1:59 PM

I managed to setup my actionbar in my activity and it works fine. But since I'm using single activity pattern, I somehow want to access the actionbar from the fragment and make some adjustments there. Do I have to make this setup all the time? :

val navController = findNavController(R.id.nav_host_fragment)
val appBarConfiguration = AppBarConfiguration(navController.graph)
findViewById<androidx.appcompat.widget.Toolbar>(R.id.toolbar).setupWithNavController(navController,appBarConfiguration)

setSupportActionBar(findViewById(R.id.toolbar))

This code is from my activity What I'm trying to do is, set this default back-arrow autogenerated button to a hamburger icon instead.

sathawale27

05/10/2020, 1:44 PM

Hey, anyone has any idea about creating a tablet emulator without a built-in hardware camera feature. So, I could test the application for my workflow.

krtko

05/11/2020, 1:54 AM

I've migrate over to Gradle's new

plugins

system and for some reason the Android plugin needs me to add

pluginManagement {
    repositories {
        gradlePluginPortal()
        jcenter()
        google()
    }
    resolutionStrategy {
        eachPlugin {
            if (requested.id.id.startsWith("com.android")) {
                useModule("com.android.tools.build:gradle:${requested.version}")
            }
        }
    }
}

to my

settings.gradle

file

Joao Birk

05/11/2020, 2:25 AM

Hi, has anyone used

ShortcutInfo.Builder

with navigation components? It needs an intent, there is no pendingIntent method that I can pass to the Builder, so cant really use

NavDeepLinkBuilder.createPendingIntent().

Leon johnson

05/12/2020, 11:33 AM

Hey guys thanks so much for accepting to this channel. Has anyone in here worked with fire base?

:stackoverflow: 1

jean

05/12/2020, 2:32 PM

I’m having some difficulties to understand how one can get an instance of a

FlowCollector

or anything build through the builder helpers function like

flow { }, callbackFlow { }, etc...

. What I want is to be able to do something like that from my fragment (or activity) but in a “correct” way

private lateinit var collector: FlowCollector<MainFragmentEvent>

private val events = flow<MainFragmentEvent> {
    collector = this
}

override onResume() {
    lifecycleScope.launch {
        collector.emit(MainFragmentEvent.ResumeEvent(requireContext()))
    }
}

Can I do that only by using

Channel, SendChannel, etc...

and then convert it some how to a

Flow

Remon Shehata

05/12/2020, 4:37 PM

//build the geofence
        val fence = Geofence.Builder()
            .setRequestId("123")
            .setCircularRegion(latitude, longitude, radiusInMeters)
            .setExpirationDuration(Geofence.NEVER_EXPIRE)
            .setTransitionTypes(Geofence.GEOFENCE_TRANSITION_ENTER)
            .build()

        geofencingRequest = GeofencingRequest.Builder().apply {
            setInitialTrigger(GeofencingRequest.INITIAL_TRIGGER_ENTER)
            addGeofence(fence)
        }.build()


        //build pending intent
        val geofencePendingIntent: PendingIntent by lazy {
            val intent = Intent(activity, GeofenceReceiver::class.java)
            PendingIntent.getBroadcast(activity, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
        }

        //request
        geofencingClient.addGeofences(geofencingRequest, geofencePendingIntent).run {
            addOnFailureListener {
                // display error
            }
            addOnSuccessListener {
                // move on
            }
        }

Remon Shehata

05/12/2020, 9:55 PM

Hello guys, Have anyone used geofencing? I am trying to use it and I am stuck..

Somesh

05/13/2020, 6:48 AM

Hello Guys, Does anyone of you have any idea why all of a sudden I started getting these errors when emitting FAILURE of Resource class which is a sealed class. it says "not enough information to infer type variable T" ? It wasn't there before. Compilation works normal. No crash. No error.

Leon johnson

05/13/2020, 7:48 PM

Hey guys I really need help please I am using Kotlin to create an Android App. The problem I am having is I’m trying to use a ViewModel to create an user in Firebase. After the user is created, something should be returned to the UI Fragment to let the fragment know to move forward to the next line of execution. The trouble I’m having is Firebase operations are done asynchronously, so there’s no way for the front end to know the operation is done executing in the view model. Is there a way to create a callback or fix this?

Gaurav K Tyagi 1

05/14/2020, 7:49 AM

Hi guys, I have a doubt Can kotlin coroutine completely replace rxJava?

antoniomarin

05/14/2020, 8:37 AM

Hello all, I’ve got one weird issue with

ViewPager2

and I cannot make any sense of it, I’ve got separate

Activity

that holds

ViewPager2

which contains fragments. That means destroying that activity with

finish()

closes

ViewPager2

as well. Now what I’ve got is beyond me, everything works fine when I start it for the first time, but if I close it and reopen my observables in the fragments won’t emit any changes, tho everything is created fine?. I’ve pinpointed issue to the

createFragment

method where commented part works but non commented doesn’t?

class PagerAdapter( 
    fragmentActivity: FragmentActivity,
    private val items: List<PagerAdapterFragment>
    //private val items: List<Int>
) : FragmentStateAdapter(fragmentActivity) {

    override fun createFragment(position: Int): Fragment {
        return items[position].fragment
//        return when (position) {
//            0 -> Fragment1.newInstance()
//            1 -> Fragment2.newInstance()
//            2 ->  PlaceholderFragment.newInstance("Retention information screen")
//            else ->  PlaceholderFragment.newInstance("Else")
//        }
    }

    data class PagerAdapterFragment(val id: Long, val fragment: Fragment)

louiscad

05/14/2020, 7:39 PM

@jw I've seen you often advocate for usage of

stdlib-jdk8

in Android, but @mbonnin research came to the conclusion that

stdlib

(not

stdlib-jdk7

) is often the best. I think I disagree since

Autocloseable.use { ... }

is quite useful for some Android APIs exposing it, and is part of

stdlib-jdk7

, but I've yet to see content

stdlib-jdk8

being used in actual Android apps, and it seems the best it has to offer is not used by Android apps because of ineffective way to determine runtime capabilities as ART isn't technically a JRE-8. If you can confirm what this article says, who can/should make the

stdlib-jdk8

content work on Android as it should? The D8/R8 team? The Kotlin team? The platform team, meaning only Android several years from now will get it? https://medium.com/@mbonnin/the-different-kotlin-stdlibs-explained-83d7c6bf293

Remon Shehata

05/15/2020, 1:25 AM

override fun checkOrganization(organizationId: String): Boolean {
    var isFound = false
    db.collection(FirebaseConstants.ORGANIZATION)
        .get()
        .addOnSuccessListener { querySnapshot ->
            for (document in querySnapshot) {
                Log.d(TAG, document.id)
                if (organizationId == document.id) {
                    isFound = true
                    
                }
            }
        }
        .addOnFailureListener { exception ->
            Log.w(TAG, "Error getting documents.", exception)
        }

    return isFound
}

I want to return from the method after the loop is completed. how to achieve that?

:stackoverflow: 2

Title

Remon Shehata

05/15/2020, 1:25 AM

override fun checkOrganization(organizationId: String): Boolean {
    var isFound = false
    db.collection(FirebaseConstants.ORGANIZATION)
        .get()
        .addOnSuccessListener { querySnapshot ->
            for (document in querySnapshot) {
                Log.d(TAG, document.id)
                if (organizationId == document.id) {
                    isFound = true
                    
                }
            }
        }
        .addOnFailureListener { exception ->
            Log.w(TAG, "Error getting documents.", exception)
        }

    return isFound
}

I want to return from the method after the loop is completed. how to achieve that?

:stackoverflow: 2

05/17/2020, 7:56 PM

Idk how this whole thing is used but what comes to mind is either passing in a callback interface to this class that is overriding

checkOrganization

and invoking the callback in the

addOnSuccessListener

. Another alternative would be changing this interface (if it's internal) and using coroutines so you can return the result asynchronously.

So a.) Use coroutines and mark

checkOrganization

a suspend function so you can return the result asynchronously. b.) Use traditional callbacks to pass the result at a later time (the end of the for loop in

addOnSuccessListener

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