Android Studio 中Kotlinx开发

-使用AndroidStudio新建一个工程，File–>Settings–>Plugins, 输入Kotlin,安装kotlin完毕后,重启AS

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-打开MainActivity，打开菜单栏Code–>选择Convert Java File to Kotlin File 或者使用快捷键Ctrl+Alt+Shift+K 转换为Kotlin文件

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-打开Tool菜单，如图所示，配置build.gradle文件 ， 然后Asyn Now

布局文件

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="simcpux.sourceforge.net.myapplication.MainActivity">    <TextView        android:id="@+id/hello"        android:layout_width="wrap_content"        android:layout_height="wrap_content"         /></RelativeLayout>

package simcpux.sourceforge.net.myapplicationimport android.support.v7.app.AppCompatActivityimport android.os.Bundleimport kotlinx.android.synthetic.main.activity_main.*class MainActivity : AppCompatActivity() {    override fun onCreate(savedInstanceState: Bundle?) {        super.onCreate(savedInstanceState)        setContentView(R.layout.activity_main)        hello.text = "kotlin"    }}

-现在运行程序会报错，如下错误Error:(5, 8) Unresolved reference: kotlinx Error:(12, 9) Unresolved reference: hello

-只需要在整个工程里配置文件里 classpath “org.jetbrains.kotlin:kotlin-android-extensions:$kotlin_version”

// Top-level build file where you can add configuration options common to all sub-projects/modules.buildscript {    ext.kotlin_version = '1.1.2-4'    repositories {        jcenter()    }    dependencies {        classpath 'com.android.tools.build:gradle:2.0.0'        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"        classpath "org.jetbrains.kotlin:kotlin-android-extensions:$kotlin_version"        // NOTE: Do not place your application dependencies here; they belong        // in the individual module build.gradle files    }}allprojects {    repositories {        jcenter()    }}task clean(type: Delete) {    delete rootProject.buildDir}

-在项目里配置文件里引用进去即可 apply plugin: ‘kotlin-android-extensions’

apply plugin: 'com.android.application'apply plugin: 'kotlin-android'apply plugin: 'kotlin-android-extensions'//启用扩展支持直接使用IDandroid {    compileSdkVersion 25    buildToolsVersion "25.0.1"    defaultConfig {        applicationId "simcpux.sourceforge.net.myapplication"        minSdkVersion 17        targetSdkVersion 25        versionCode 1        versionName "1.0"    }    buildTypes {        release {            minifyEnabled false            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'        }    }    sourceSets {        main.java.srcDirs += 'src/main/kotlin'    }}dependencies {    compile fileTree(dir: 'libs', include: ['*.jar'])    testCompile 'junit:junit:4.12'    compile 'com.android.support:appcompat-v7:25.0.1'    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"}repositories {    mavenCentral()}

-运行成功