Kotlin初体验

这两天看都在讨论Kotlin，也来试试，感觉不错，是更精简方便了。重要是可以用IDE，这两天看Python头疼，但它却自动转换！！冲这一点就牛B，更别说更方便响应式编写

给Android Studio安装Kotlin

file->Setitngs->Plugins->搜索Kotlin进行安装->重启AS

新建Android Studio工程

将MainActivity转换为Kontlin语言

ctrl+shift+a->输入Convert Java F，选择Convert Java File to Kontlin File

ctrl+shift+a->输入configure k，选择Configure Kontlin in Project

这两条更新要一些时间，更新完之后就可以运行了

Code

• MainActivity

package com.xuie.kotlindemoimport android.os.Bundleimport android.support.design.widget.FloatingActionButtonimport android.support.design.widget.Snackbarimport android.support.v7.app.AppCompatActivityimport android.support.v7.widget.Toolbarimport android.view.Menuimport android.view.MenuItemclass MainActivity : AppCompatActivity() {    override fun onCreate(savedInstanceState: Bundle?) {        super.onCreate(savedInstanceState)        setContentView(R.layout.activity_main)        val toolbar = findViewById(R.id.toolbar) as Toolbar        setSupportActionBar(toolbar)        val fab = findViewById(R.id.fab) as FloatingActionButton        fab.setOnClickListener { view -> Snackbar.make(view, "Replace with your own action, I'm kotlin", Snackbar.LENGTH_LONG).setAction("Action", null).show() }    }    override fun onCreateOptionsMenu(menu: Menu): Boolean {        // Inflate the menu; this adds items to the action bar if it is present.        menuInflater.inflate(R.menu.menu_main, menu)        return true    }    override fun onOptionsItemSelected(item: MenuItem): Boolean {        // Handle action bar item clicks here. The action bar will        // automatically handle clicks on the Home/Up button, so long        // as you specify a parent activity in AndroidManifest.xml.        val id = item.itemId        //noinspection SimplifiableIfStatement        if (id == R.id.action_settings) {            return true        }        return super.onOptionsItemSelected(item)    }}

• app/build.gradle

apply plugin: 'com.android.application'apply plugin: 'kotlin-android'android {    compileSdkVersion 23    buildToolsVersion "23.0.2"    defaultConfig {        applicationId "com.xuie.kotlindemo"        minSdkVersion 15        targetSdkVersion 23        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-v7:23.1.1'    compile 'com.android.support:design:23.1.1'    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"}buildscript {    ext.kotlin_version = '1.0.0'    repositories {        mavenCentral()    }    dependencies {        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"    }}repositories {    mavenCentral()}

参考

https://kotlinlang.org/docs/tutorials/kotlin-android.html
http://blog.jetbrains.com/kotlin/2013/08/working-with-kotlin-in-android-studio/