Coroutines in UI example

Coroutines1.kt

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_login)

    progress_auth.visibility = View.VISIBLE

    button_auth.setOnClickListener {
        val actionBar = supportActionBar
      
        GlobalScope.launch(Dispatchers.Main) {
            // testAsync() doesn't block UI, returns Deferred<String>
            val newTitle = testAsync()
            // Let's get String from Deferred<String>:
            actionBar?.title = newTitle.await()
        }
    }
}

private fun waitAndReturnNewTitle(): String {
    Thread.sleep(5000)
    return "new_title"
}

private fun testAsync() = GlobalScope.async(Dispatchers.Default) { waitAndReturnNewTitle() }

Coroutines2.kt

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_login)

    progress_auth.visibility = View.VISIBLE

    button_auth.setOnClickListener {
        val actionBar = supportActionBar

        GlobalScope.launch(Dispatchers.Main) {
            // testAsync() doesn't block UI, returns String
            val newTitle = testAsync()
            actionBar?.title = newTitle
        }
    }
}

private fun waitAndReturnNewTitle(): String {
    Thread.sleep(5000)
    return "new_title"
}

private suspend fun testAsync(): String = withContext(Dispatchers.Default) { waitAndReturnNewTitle() }