Kotlin 从片段(fragment)中的点击事件启动协同程序

You need a job to handle the coroutine cancelation to prevent leaks:

//inside Fragment
val job = Job()
val uiScope = CoroutineScope(Dispatchers.Main + job)


//late in the button click

button.setOnClickListener{
  uiScope.launch(Dispatchers.IO){
    //asyncOperation
    withContext(Dispatchers.Main){
     //ui operation
   }

  }
}

//later in on destroy:

override fun onDestroy(){
  job.cancel()
  super.onDestroy()
}

你也可以使用谷歌的LifecycleScope extension:

class MyFragment: Fragment() {
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        lifecycleScope.launch {
            val params = TextViewCompat.getTextMetricsParams(textView)
            val precomputedText = withContext(Dispatchers.Default) {
                PrecomputedTextCompat.create(longTextContent, params)
            }
            TextViewCompat.setPrecomputedText(textView, precomputedText)
        }
    }
}

编辑，以防重新启动另一个操作.只需使用相同的范围:

//let's assume you have a second button

button2.setOnClickListener{
  uiScope.launch(Dispatchers.IO){
    //perform second operation
  }
}