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新建package  basic

新建BaseCoroutines.kt

package com.yzdzy.kotlin.chapter7.basicimport cn.kotliner.coroutine.common.HttpErrorimport cn.kotliner.coroutine.common.HttpExceptionimport cn.kotliner.coroutine.common.HttpServiceimport cn.kotliner.coroutine.common.logimport cn.kotliner.coroutine.ui.LOGO_URLimport java.lang.Exceptionimport javax.xml.ws.http.HTTPExceptionimport kotlin.coroutines.resumeimport kotlin.coroutines.resumeWithExceptionimport kotlin.coroutines.startCoroutineimport kotlin.coroutines.suspendCoroutinefun 我要开始协程了(block: suspend () -> Unit) {    block.startCoroutine(BaseCoroutines())}suspend fun 我要开始加载图片了(url: String) = suspendCoroutine
   
     { continuation ->    log("耗时下载图片")  try {      val reponseBody = HttpService.service.getLogo(LOGO_URL).execute()      if (reponseBody.isSuccessful) {          reponseBody.body()?.byteStream()?.readBytes()?.let(continuation::resume)      }else{          continuation.resumeWithException(HttpException(reponseBody.code()))      }  }catch (e:Exception){      continuation.resumeWithException(e)  }}
   

新建 Corutines.kt

package com.yzdzy.kotlin.chapter7.basicimport kotlin.coroutines.Continuationimport kotlin.coroutines.CoroutineContextimport kotlin.coroutines.EmptyCoroutineContextclass BaseCoroutines: Continuation
   
     {    override val context: CoroutineContext        get() = EmptyCoroutineContext    override fun resumeWith(result: Result
    
     ) {    }}
    
   

在刚才的common包中新建

Log.kt

package cn.kotliner.coroutine.commonimport java.text.SimpleDateFormatimport java.util.*/** * Created by benny on 5/20/17. */val dateFormat = SimpleDateFormat("HH:mm:ss:SSS")val now = {    dateFormat.format(Date(System.currentTimeMillis()))}fun log(msg: String) = println("${now()} [${Thread.currentThread().name}] $msg")

新建 Https.kt  为了抛异常使用

package cn.kotliner.coroutine.common/** * Created by benny on 5/20/17. */object HttpError{    const val HTTP_ERROR_NO_DATA = 999    const val HTTP_ERROR_UNKNOWN = 998}data class HttpException(val code: Int): Exception()

修改MainKt.kt

package cn.kotliner.coroutine.uiimport cn.kotliner.coroutine.common.HttpErrorimport cn.kotliner.coroutine.common.HttpServiceimport cn.kotliner.coroutine.common.logimport com.yzdzy.kotlin.chapter7.basic.我要开始加载图片了import com.yzdzy.kotlin.chapter7.basic.我要开始协程了import okhttp3.ResponseBodyimport retrofit2.Callimport retrofit2.Callbackimport retrofit2.HttpExceptionimport retrofit2.Responseimport javax.swing.JFrame.EXIT_ON_CLOSEimport javax.swing.SwingUtilities/** * Created by benny on 5/20/17. */const val LOGO_URL = "http://www.imooc.com/static/img/index/logo.png?t=1.1"fun main(args: Array
   
    ) {    val frame = MainWindow()    frame.title = "Coroutine@Bennyhuo"    frame.setSize(200, 150)    frame.isResizable = true    frame.defaultCloseOperation = EXIT_ON_CLOSE    frame.init()    frame.isVisible = true    frame.onButtonClick {        log("协程之前")        我要开始协程了 {            log("协程开始")            val imageDate = 我要开始加载图片了(LOGO_URL)            log("拿到图片")            frame.setLogo(imageDate)        }        log("协程之后")    }}
   

查看logo

这说明协程并非异步。下面我们要把他切换到异步

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