Kotlin starts the process, the difference between launch and async, and starts the process in sequence

 launch And async The difference between

       binding.btClick5.setOnClickListener {
            // The main thread executes the coroutine 
            runBlocking {
                //launch  The execution result will not be returned 
                val job1 = launch {
                    delay(200)
                    Log.e(TAG, "onCreate: jbo1 finished.")
                }
                // async  The execution result will be returned 
                val job2 = async {
                    delay(200)
                    Log.e(TAG, "onCreate: job2 finished.")
                    "job2 result"
                }
                Log.e(TAG, "onCreate${ job2.await() }")
            }
        }

Start the process in sequence

Now there are three processes . Want to start first 1

Then start up 2 and 3

How to operate ,

luanch Start up Use join function

       binding.btClick5.setOnClickListener {
            // The main thread executes the coroutine 
            runBlocking {
                //launch  The execution result will not be returned 
                val job1 = launch {
                    delay(2000)
                    Log.e(TAG, "One")
                }
                job1.join()

                val job2 = launch {
                    delay(200)
                    Log.e(TAG, "Two")
                }
                val job3 = launch {
                    delay(200)
                    Log.e(TAG, "Three")
                }
            }
        }

async Words Use await

      binding.btClick5.setOnClickListener {
            // The main thread executes the coroutine 
            runBlocking {
                //launch  The execution result will not be returned 
                val job1 = async {
                    delay(2000)
                    Log.e(TAG, "One")
                }
                job1.await()

                val job2 = async {
                    delay(200)
                    Log.e(TAG, "Two")
                }
                val job3 = async {
                    delay(200)
                    Log.e(TAG, "Three")
                }
            }
        }

 join and await Are all suspended functions , Will not block the main thread