Anko Coroutines

Contents

• Using Anko Coroutines in your project
• Listener helpers
• asReference()
• bg()

Using Anko Coroutines in your project

Add the anko-coroutines dependency to your build.gradle:

dependencies {
    implementation "org.jetbrains.anko:anko-coroutines:$anko_version"
}

Listener helpers

asReference()

If your asynchronous API does not support cancellation, your coroutine may be suspended for an indefinite time period. As a coroutine holds the strong references to captured objects, capturing the instance of Activity or Fragment instance may cause a memory leak.

Use asReference() in such cases instead of the direct capturing. (Please note that Anko's method async is considered deprecated, so as to not conflict with the kotlinx.coroutines function by the same name. Use doAsync instead.)

suspend fun getData(): Data { ... }

class MyActivity : Activity() {
    fun loadAndShowData() {
		// Ref<T> uses the WeakReference under the hood
		val ref: Ref<MyActivity> = this.asReference()
	
		async(UI) {
		    val data = getData()
				
		    // Use ref() instead of this@MyActivity
		    ref().showData(data)
		}
    }

    fun showData(data: Data) { ... }
}

bg()

Please note that the bg function is deprecated, as well as Anko's async function demonstrated in this example.

You can easily execute your code on the background thread using bg():

fun getData(): Data { ... }
fun showData(data: Data) { ... }

async(UI) {
    val data: Deferred<Data> = bg {
		// Runs in background
		getData()
    }

    // This code is executed on the UI thread
    showData(data.await())
}