Merge branch 'step3'

Author: Dominik Liebler

README.md

@@ -5,3 +5,4 @@ This is the example from my [blog post with the same title](https://domnikl.gith
 - [Step 0](https://github.com/domnikl/kotlin-coroutines-and-javafx-threads/blob/step0/src/main/kotlin/Main.kt) 
 - [Step 1](https://github.com/domnikl/kotlin-coroutines-and-javafx-threads/blob/step1/src/main/kotlin/Main.kt)
 - [Step 2](https://github.com/domnikl/kotlin-coroutines-and-javafx-threads/blob/step2/src/main/kotlin/Main.kt)
+- [Step 3](https://github.com/domnikl/kotlin-coroutines-and-javafx-threads/blob/step3/src/main/kotlin/Main.kt)

src/main/kotlin/Main.kt

@@ -8,9 +8,12 @@ import kotlinx.coroutines.*
 import kotlinx.coroutines.javafx.JavaFx
 import kotlin.coroutines.CoroutineContext
 
-class MillisElapsedCounter(private val observer: Observer) {
+class MillisElapsedCounter(private val observer: Observer) : CoroutineScope {
+    override val coroutineContext: CoroutineContext
+        get() = Dispatchers.Default
+
     fun start() {
-        GlobalScope.launch(Dispatchers.Default) {
+        launch {
             var millisElapsed = 0
 
             while (true) {