UPDATE: Kotlin coroutines are no longer experimental as of Kotlin 1.3. Kotlin coroutines can and should be used in production. That was the chief reason to officially release them in Kotlin 1.1. Having released them, the JetBrains team had committed to maintain backwards compatibility with respect to any changes that are introduced to them in … Read more
I can observe LiveData from multiple Fragments. Can I do this with Flow? If yes then how? Yes. You can do this with emit and collect. Think emit is similar to live data postValue and collect is similar to observe. Lets give an example. Repository // I just faked the weather forecast val weatherForecast = … Read more
Android Studio’s UI was just hiding the error… when the error occurred, it highlighted the item in the list view, and showed an unhelpful message in the terminal view. to find the real error, select the root item in the list view so that Android Studio would display the whole build output in the terminal … Read more
First, let’s start with definitions to make it clear. If you need a tutorial or playground for Coroutines and Coroutines Flow you can check out this tutorial/playground i created. Scope is object you use to launch coroutines that only contains one object which is CoroutineContext public interface CoroutineScope { /** * The context of this … Read more
In this particular case you can use a general approach to convert a callback-based API to a suspending function via suspendCoroutine function: suspend fun CameraManager.openCamera(cameraId: String): CameraDevice? = suspendCoroutine { cont -> val callback = object : CameraDevice.StateCallback() { override fun onOpened(camera: CameraDevice) { cont.resume(camera) } override fun onDisconnected(camera: CameraDevice) { cont.resume(null) } override fun … Read more
I don’t understand how coroutineScope and runBlocking are different here? coroutineScope looks like its blocking since it only gets to the last line when it is done. There are two separate worlds: the suspendable world (within a coroutine) and the non-suspendable one. As soon as you enter the body of runBlocking, you are in the … Read more
What does it mean that a coroutine is like a lightweight thread? Coroutine, like a thread, represents a sequence of actions that are executed concurrently with other coroutines (threads). What is the difference? A thread is directly linked to the native thread in the corresponding OS (operating system) and consumes a considerable amount of resources. … Read more
Large number of coroutines, though lightweight, could still be a problem in demanding applications I’d like to dispel this myth of “too many coroutines” being a problem by quantifying their actual cost. First, we should disentangle the coroutine itself from the coroutine context to which it is attached. This is how you create just a … Read more
Use liveData.postValue(value) instead of liveData.value = value. It called asynchronous. From documentation: postValue – Posts a task to a main thread to set the given value.
You can directly use Executors from java.util.concurrent package. I also searched about it and I found a solution in this Android Async API is Deprecated post. Unfortunately, the post is using Kotlin, but after a little effort I have converted it into Java. So here is the solution. ExecutorService executor = Executors.newSingleThreadExecutor(); Handler handler = … Read more