Kotlin 在协程中等待侦听器内的数据

第一点是，我会将loadData函数更改为挂起函数，而不是使用launch.最好 Select 在调用点定义您希望如何继续执行.例如，在实现测试时，您可能希望在runBlocking中调用协程.您还应该正确实现structured concurrency，而不是依赖GlobalScope.

On the other side of the problem I would implement an extension function on the ThirdPartyLibrary that turns its async calls into a suspending function. This way you will ensure that the calling coroutine actually waits for the Library call to have some value in it.

由于我们将loadData设为挂起函数，现在可以确保它只在ThirdPartyLibrary调用结束时启动新活动.

import kotlinx.coroutines.*
import kotlin.coroutines.*

class InitialActivity : AppCompatActivity(), CoroutineScope {
    private lateinit var masterJob: Job
    override val coroutineContext: CoroutineContext
        get() = Dispatchers.Main + masterJob

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        masterJob = Job()
    }

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

    override fun onResume() {
        this.launch {
            val data = ThirdPartyLibrary().suspendLoadData()
            // TODO: act on data!
            startActivity(startNewIntent)
        }
    }
}

suspend fun ThirdPartyLibrary.suspendLoadData(): Data = suspendCoroutine { cont ->
    setOnDataListener(
            onSuccess = { cont.resume(it) },
            onFail = { cont.resumeWithException(it) }
    )
    startLoadingData()
}