coroutines kotlin code example

Example 1: coroutines kotlin android dependency

dependencies {
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.7'
}

Example 2: coroutines kotlin android dependency

implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.7'

Example 3: kotlin coroutine scope

CoroutineScope
To start coroutine scope you can:
Use GlobalScope that has empty coroutine context.
Implement CoroutineScope interface.
Create a scope from a context:
with(CoroutineScope(context = context)) { ... }

Example 4: kotlin coroutines

import kotlinx.coroutines.*
// Asynchronous execution
fun main() {
  GlobalScope.launch { 	// creates a new coroutine and continues
    doWorld()			// suspending function
  }
  println("World !") 	// execution continues even while coroutine waits
  runBlocking { 		// block main thread for 4 s (waits for 1rst coroutine)
  	delay(4000L) 		
  }
}
suspend fun doWorld() {
  delay(2000L) 		// non-blocking delay for 2000 milliseconds
  println("Hello")	// printed after "World !"
}

Example 5: kotlin coroutines dependency

implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.4.1'

Example 6: kotlin coroutine builders

launch - Launches new coroutine without blocking
current thread and returns a reference to the coroutine
as a Job.
runBlocking - Runs new coroutine and blocks current
thread interruptible until its completion.
async - Creates new coroutine and returns its future
result as an implementation of Deferred.
withContext - Change a coroutine context for some
block.