Android: Gradle quick start

1, Gradle what is?

gradle with ant / maven, it is a dependency management / automated build tools. But with ant / maven is not the same, it abandoned the complicated configuration based on a variety of XML, based on the internal replaced by a specific field Groovy (DSL) language, for Java-based applications. This makes it more simple, flexible and more powerful is, gradle fully compatible with maven and ivy.

More details can be seen on its official website: http://www.gradle.org/

2, Why?

• More powerful code hinting and easy to operate;
• Easier to configure, extended;
• More powerful dependency management, version control
• Better integration IDE

 AS in gradle

File directory structure

build.gradle under the project

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    //指定远程中央仓库
    repositories {
        google()
        //jcenter指向的是: https://jcenter.bintray.com/，兼容maven中心仓库，性能更优
        jcenter()
        
    }
    //指定整个工程的依赖
    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.0'
        
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}
//所有工程及其modle都使用jcenter、google中央仓库
allprojects {
    repositories {
        google()
        jcenter()
        
    }
}
//执行delete构建时, 删除工程下所有构建产生的文件夹
task clean(type: Delete) {
    delete rootProject.buildDir
}

module 下的 build.gradle

// 声明是Android程序
apply plugin: 'com.android.application'

android {
    // 指定编译SDK的版本
    compileSdkVersion 28
    defaultConfig {
        // 应用的包名
        applicationId "com.example.recyclerdome"
        //最小版本
        minSdkVersion 16
        //目标版本
        targetSdkVersion 28
        versionCode 1
        //应用版本号
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            // 是否进行代码混淆
            minifyEnabled false
            // 混淆配置文件的位置
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}
//包含所有依赖的jar或库
dependencies {
    // 编译libs目录下的所有jar包
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    //测试时才编译junit包
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
    implementation 'androidx.recyclerview:recyclerview:1.0.0'
    implementation 'androidx.cardview:cardview:1.0.0'
}

settings.gradle  // This file is global project configuration files

gradle folder and its subfolders

contain

gradle-wrapper.jar

gradle-wrapper.properties

These two are gradle two required files , creating Project automatically generated , we need not modify