Add small example about how delay works

Author: LukasLechnerDev

app/src/main/java/com/lukaslechner/coroutineusecasesonandroid/playground/fundamentals/10_how_delay_works.kt

@@ -0,0 +1,27 @@
+package com.lukaslechner.coroutineusecasesonandroid.playground.fundamentals
+
+import android.os.Handler
+import android.os.Looper
+import kotlinx.coroutines.async
+import kotlinx.coroutines.joinAll
+import kotlinx.coroutines.runBlocking
+
+fun main() = runBlocking {
+    println("main starts")
+    joinAll(
+        async { delayDemonstration(1, 500) },
+        async { delayDemonstration(2, 300) }
+    )
+    println("main ends")
+}
+
+suspend fun delayDemonstration(number: Int, delay: Long) {
+    println("Coroutine $number starts work")
+
+    // delay(delay)
+
+    Handler(Looper.getMainLooper())
+        .postDelayed({
+            println("Coroutine $number has finished")
+        }, 500)
+}