Coroutines Splash

SplashActivity.kt

class SplashActivity : Activity() {
  
  private val creationTime = System.currentTimeMillis()
  private var splashJob: Job? = null
  
  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    
    initializeApp()
  }
  
  private fun initializeApp() {
    splashJob?.cancel()
    
    splashJob = launch(UI) {
      try {
        // For each task, create a child coroutine
        val userSessionJob = async(coroutineContext) { userSession.init() }
        val supportInfoJob = async(coroutineContext) { supportInfoHelper.updateInfo() }
        
        // Just calling delay(MIN_SHOW_TIME) would be incorrect for retries
        val delayTime = (creationTime + MIN_SHOW_TIME) - System.currentTimeMillis()
        if (delayTime > 0) {
          delay(delayTime)
        }
        
        // Calling this a second time is not a problem
        progressBar.visibility = View.VISIBLE
        
        // By await'ing after creating all child coroutines we make
        // sure that they can run in parallel
        userSessionJob.await()
        supportInfoJob.await()
        
        // All good, we're done
        setResult(Activity.RESULT_OK)
        finish()
      } catch (error: Error) {
        showRetryAlert(error,
                       onRetry = { initializeApp() },
                       onCancel = { finish() })
      }
    }
  }
  
}