newSingleThreadContext("Ctx1").use { ctx1 ->
    newSingleThreadContext("Ctx2").use { ctx2 ->
        runBlocking(ctx1) {
            log("Started in ctx1")
            withContext(ctx2) {
                log("Working in ctx2")
            }
            log("Back to ctx1")
        }
    }
}

launch(newSingleThreadContext("MyOwnThread")) { // will get its own new thread
    println("newSingleThreadContext: I'm working in thread ${Thread.currentThread().name}")
}

https://kotlinlang.org/docs/coroutine-context-and-dispatchers.html#jumping-between-threads

导入协程

    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.6.4")
    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.4")
    implementation 'org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.10'

全局协程测试

       coroutineIoScope.launch {
            Timber.e("coroutineIoScope thread id = " + Thread.currentThread().id)
        }
        coroutineDbScope.launch {
            Timber.e("coroutineDbScope thread id = " + Thread.currentThread().id)
        }
        coroutineFileScope.launch {
            Timber.e("coroutineFileScope thread id = " + Thread.currentThread().id)
        }
        coroutineMainScope.launch {
            Timber.e("coroutineMainScope thread id = " + Thread.currentThread().id)
        }
        Timber.e("Main thread id = " + Thread.currentThread().id)

协程文件

@file:OptIn(DelicateCoroutinesApi::class)

package com.mgg.core.coroutine

import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.DelicateCoroutinesApi
import kotlinx.coroutines.MainScope
import kotlinx.coroutines.newSingleThreadContext

// https://www.jianshu.com/p/76d2f47b900d
val singleIOThreadContext = newSingleThreadContext("CoroutineIoScope")

val singleDBThreadContext = newSingleThreadContext("CoroutineDbScope")

val singleFileThreadContext = newSingleThreadContext("CoroutineFileScope")

val coroutineIoScope = CoroutineScope(singleIOThreadContext)

val coroutineDbScope = CoroutineScope(singleDBThreadContext)

val coroutineFileScope = CoroutineScope(singleFileThreadContext)

val coroutineMainScope = MainScope()