Android: build.gradle.ktsのすゝめ

Github

環境

tool	version
Gradle	5.4.1
Kotlin	1.3.41
Android Studio	3.5 Beta 5
Android Gradle Plugin	3.5.0-beta05

既存のプロジェクトへの導入

設定の変更
ファイル - 設定 - 言語＆フレームワーク - Kotlin - Kotlinスクリプト
ファイル変更時にスクリプト依存関係を再ロードするにチェックする
プロジェクトルートに buildSrc を作成
buildSrc に build.gradle.kts と settings.gradle.kts を作成
build.gradle.kts に記述

build.gradle.kts

plugins {
    `kotlin-dsl`
}
repositories {
    jcenter()
    google()
}
dependencies {
    implementation("com.android.tools.build:gradle:3.5.0-beta05")
    implementation("org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.41")
}

Sync now(今すぐ同期)
プロジェクトルートの settings.gradle を settings.gradle.kts にリネーム
settings.gradle.kts を編集

settings.gradle.kts

include(":app")
rootProject.name = "My Application"

プロジェクトルートの build.gradle を build.gradle.kts にリネーム
build.gradle.kts を編集

build.gradle.kts

buildscript {
    repositories {
        google()
        jcenter()        
    }
    dependencies {
        classpath("com.android.tools.build:gradle:3.5.0-beta05")
        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.41")
    }
}
allprojects {
    repositories {
        google()
        jcenter()
       
    }
}
task<Delete>("clean") { delete(rootProject.buildDir) }

app/build.gradle を app/build.gradle.kts にリネーム
app/build.gradle.kts を編集

app/build.gradle.kts

plugins {
    id("com.android.application")
    id("kotlin-android")
    id("kotlin-android-extensions")
}
android {
    compileSdkVersion(29)
    buildToolsVersion = "29.0.0"
    defaultConfig {
        applicationId = "com.sorrowblue.myapplication"
        minSdkVersion(23)
        targetSdkVersion(29)
        versionCode =1
        versionName ="1.0"
        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        getByName("release") {
            isMinifyEnabled = false
            proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
        }
    }
}
dependencies {
    implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.3.41")
    implementation("androidx.appcompat:appcompat:1.0.2")
    implementation("androidx.core:core-ktx:1.0.2")
    implementation("androidx.constraintlayout:constraintlayout:1.1.3")
    testImplementation("junit:junit:4.12")
    androidTestImplementation("androidx.test.ext:junit:1.1.0")
    androidTestImplementation("androidx.test.espresso:espresso-core:3.1.1")
}

Sync now(今すぐ同期)

スマートに書く

getByName("release") このあたりを拡張関数で記述する

buildSrc/src/main/kotlin/Project.kt を作成

buildSrc/src/main/kotlin/Project.kt

import com.android.build.gradle.internal.dsl.BuildType
import org.gradle.api.NamedDomainObjectContainer
fun NamedDomainObjectContainer<BuildType>.release(body: BuildType.() -> Unit) {
    getByName("release") { body(this) }
}

app/build.gradle.kts

release {
	isMinifyEnabled = false
	proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
}

変数を定義

もちろん変数も定義して使える

buildSrc/src/main/kotlin/Versions.kt を作成

buildSrc/src/main/kotlin/Versions.kt

object Versions {
	const val kotlin = "1.3.41"
	const val appcompat = "1.0.2"
	const val `core-ktx` = "1.0.2"
	const val constraintlayout = "1.1.3"
	const val junit = "4.12"
    const val androidx_junit = "1.1.0"
    const val `espresso-core` = "3.1.1"
}

buildSrc/src/main/kotlin/Deps.kt を作成

buildSrc/src/main/kotlin/Deps.kt

object Deps {
	const val `kotlin-stdlib-jdk7` = "org.jetbrains.kotlin:kotlin-stdlib-jdk7:${Versions.kotlin}"
	const val appcompat = "androidx.appcompat:appcompat:${Versions.appcompat}"
    const val `core-ktx` = ("androidx.core:core-ktx:${Versions.`core-ktx`}")
    const val constraintlayout = "androidx.constraintlayout:constraintlayout:${Versions.constraintlayout}"
    const val junit = "junit:junit:${Versions.junit}"
    const val androidx_junit = "androidx.test.ext:junit:${Versions.androidx_junit}"
    const val `espresso-core` = "androidx.test.espresso:espresso-core:${Versions.`espresso-core`}"
}

app/build.gradle.kts

dependencies {
    implementation(Deps.`kotlin-stdlib-jdk7`)
    implementation(Deps.appcompat)
    implementation(Deps.`core-ktx`)
    implementation(Deps.constraintlayout)
    testImplementation(Deps.junit)
    androidTestImplementation(Deps.androidx_junit)
    androidTestImplementation(Deps.`espresso-core`)
}

Tips

各モジュールの `minSdkVersion` `targetSdkVersion` などをまとめる

Project.kt

build.gradle.kts

fun Project.module(action: LibraryExtension.() -> Unit) {
	afterEvaluate {
		if (hasProperty("android") && project.name != "app") {
			action(extensions.getByName("android") as LibraryExtension)
		}
	}
}

build.gradle.kts

build.gradle.kts

subprojects {
	module {
		compileSdkVersion(COMPILE_SDK_VERSION)
		defaultConfig {
			minSdkVersion(MIN_SDK_VERSION)
			targetSdkVersion(TARGET_SDK_VERSION)
			consumerProguardFiles(`consumer-rules`)
			testInstrumentationRunner = ANDROID_JUNIT_RUNNER
		}
	}
}

任意の箇所でapplyしたいとき

app/build.gradle.kts

app/build.gradle.kts

plugins {
	id("com.google.gms.google-services") apply false
}
/*..........processing..........*/
apply(plugin = "com.google.gms.google-services")

プラグインを共通化したい

build.gradle.kts

build.gradle.kts

subprojects {
	if (project.name == "app") {
		apply(plugin = "com.android.application")
	} else {
		apply(plugin = "com.android.library")
	}
	apply(plugin = "kotlin-android")
	apply(plugin = "kotlin-android-extensions")
}