Android Gradle使用總結（1）

Android Gradle使用篇：

Android Gradle使用總結（1）

Android Gradle使用總結（2）

Gradle是一款優秀的構建系統工具，它的DSL(領域特定語言)基於Groovy實現，能夠方便地經過代碼控制這些DSL來達到構建的目的。

注：執行gradle命令時，默認加載當前目錄下的build.gradle文件，亦能夠經過-b 指定要加載的執行文件，如： gradlew -b ./app/build.gradle assemble

Gradle經常使用基礎

一、記得使用幫助

（1）查看全部可執行的任務（Tasks）

gradlew tasks

Gradle會以分組的方式列出task列表，好比構建類的 assemable，幫助類的 help等

------------------------------------------------------------
All tasks runnable from root project
------------------------------------------------------------

Android tasks
-------------
androidDependencies - Displays the Android dependencies of the project.
signingReport - Displays the signing info for each variant.
sourceSets - Prints out all the source sets defined in this project.

Build tasks
-----------
assemble - Assembles all variants of all applications and secondary packages.
assembleAndroidTest - Assembles all the Test applications.
assembleDebug - Assembles all Debug builds.
assembleRelease - Assembles all Release builds.
build - Assembles and tests this project.
buildDependents - Assembles and tests this project and all projects that depend on it.
buildNeeded - Assembles and tests this project and all projects it depends on.
bundleDebug - Creates all Debug bundles.
bundleRelease - Creates all Release bundles.
clean - Deletes the build directory.
cleanBuildCache - Deletes the build cache directory.
compileDebugAndroidTestSources
compileDebugSources
compileDebugUnitTestSources
compileReleaseSources
compileReleaseUnitTestSources

Build Setup tasks
-----------------
init - Initializes a new Gradle build.
wrapper - Generates Gradle wrapper files.

Cleanup tasks
-------------
lintFix - Runs lint on all variants and applies any safe suggestions to the source code.

Help tasks
----------
buildEnvironment - Displays all buildscript dependencies declared in root project 'tapeView'.
components - Displays the components produced by root project 'tapeView'. [incubating]
dependencies - Displays all dependencies declared in root project 'tapeView'.
dependencyInsight - Displays the insight into a specific dependency in root project 'tapeView'.
dependentComponents - Displays the dependent components of components in root project 'tapeView'. [incubating]
help - Displays a help message.
model - Displays the configuration model of root project 'tapeView'. [incubating]
projects - Displays the sub-projects of root project 'tapeView'.
properties - Displays the properties of root project 'tapeView'.
tasks - Displays the tasks runnable from root project 'tapeView' (some of the displayed tasks may belong to subprojects).

Install tasks
-------------
installDebug - Installs the Debug build.
installDebugAndroidTest - Installs the android (on device) tests for the Debug build.
installRelease - Installs the Release build.
uninstallAll - Uninstall all applications.
uninstallDebug - Uninstalls the Debug build.
uninstallDebugAndroidTest - Uninstalls the android (on device) tests for the Debug build.
uninstallRelease - Uninstalls the Release build.

Verification tasks
------------------
check - Runs all checks.
connectedAndroidTest - Installs and runs instrumentation tests for all flavors on connected devices.
connectedCheck - Runs all device checks on currently connected devices.
connectedDebugAndroidTest - Installs and runs the tests for debug on connected devices.
deviceAndroidTest - Installs and runs instrumentation tests using all Device Providers.
deviceCheck - Runs all device checks using Device Providers and Test Servers.
lint - Runs lint on all variants.
lintDebug - Runs lint on the Debug build.
lintRelease - Runs lint on the Release build.
lintVitalRelease - Runs lint on just the fatal issues in the release build.
test - Run unit tests for all variants.
testDebugUnitTest - Run unit tests for the debug build.
testReleaseUnitTest - Run unit tests for the release build.

To see all tasks and more detail, run gradle tasks --all

To see more detail about a task, run gradle help --task <task>

BUILD SUCCESSFUL in 18s
1 actionable task: 1 executed
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（2）Gradle Help任務

gradle內置的help任務，能夠了解每個Task的使用幫助，用法是gradlew help --task <taskName> 如：gradlew help --task assemable

二、強制刷新依賴

gradlew --refresh-dependencies assemable

三、多任務執行

只需按順序以空格分開便可，如gradlew clean jar，先執行clean再執行生成jar

四、自定義屬性

自定義屬性具備更普遍的做用域，能夠跨Project，跨Task訪問。只要能訪問這些屬性所屬的對象，那麼這些屬性就能夠被訪問到。

apply plugin: "java"

ext.age = 18 //自定義一個屬性

//自定義多個屬性
ext{
	phone = '020'
	address = ''

	dep = [android : "androidan"] //map
}


sourceSets.all{
	ext.resourcesDir = null
}

sourceSets {
	main{
		resourcesDir="main/res"
	}
	test{
		resourcesDir="test/res"
	}
}

task customProperty{
	doLast{
		println "age: ${age}"
		println "phone: $phone"
		println "address: $address"
		println "android: ${dep.android}"

		sourceSets.each{
			println"${it.name}'s resourcesDir is: ${it.resourcesDir}"
		}
	}
	
}
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五、任務的禁用和開啓

任務禁用時，當執行到該任務，會skip掉

task task1{
    doLast{
        println 'xxx'
    }
}

task1.enabled = false; //false:禁用，true:開啓
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六、任務的onlyif 斷言

任務有一個onlyIf方法，接收一個閉包做爲參數，若是該閉包返回true，則該任務執行，不然跳過

以鍵值對的形式添加屬性：-PK=V，中間不能有空格 ，如：gradle -Pbuild_apps=shoufa build

final String BUILD_APPS_ALL="all";
final String BUILD_APPS_SHOUFA="shoufa";
final String BUILD_APPS_EXCLUDE_SHOUFA="exclude_shoufa";

task QQRelease{
	doLast{
		println "QQRelease"
	}
    
}
task BaiduRelease{
	doLast{
		println "BaiduRelease"
	}
   
}

task build{
	group BasePlugin.BUILD_GROUP
	description '打渠道包'
	dependsOn QQRelease,BaiduRelease
}

QQRelease.onlyIf{
	if (project.hasProperty('build_apps')) {
		Object buildApps = project.property("build_apps")
		if (BUILD_APPS_SHOUFA.equals(buildApps)) {
			return false
		}
	}
	return true;
}

//gradle -Pbuild_apps=shoufa build; //以鍵值對的形式添加屬性：-PK=V，中間不能有空格
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七、腳本即代碼，代碼也是腳本

雖然Gradle是個腳本文件，但寫的依舊是代碼，Groovy是兼容Java的，能靈活實現不少功能。如，給生成的apk以當前時間命名：

def buildTime(){
    def date = new Date()
    def formattedDate = data.format('yyyyMMdd')
    return formattedDate
}
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Groovy基礎

一、字符串

單引號和雙引號都能定義字符串。區別在於，單引號表示純粹的字符串常量，而雙引號具備運算能力。 如:

def name = "John"
println '單引號${name}' //輸出: 單引號${name}
println "雙引號${name}"  //輸出: 雙引號John
println "雙引號$name"   //輸出: 雙引號John
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一個美圓符號緊接着一對花括號，花括號裏放表達式，如${name}，當只有一個變量時，能夠省略花括號，如$name;

二、集合

（1）List

def nums = [1,2,3,4] //定義arrayList
println nums[1]  //下標索引訪問
nums.each{
    println it //forEach,其中it變量爲正在迭代的元素
}
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（2）Map

def map = ['width':1024,'height':768] //定義map
println map['width'] //訪問
println map.height //訪問
map.each{
    println "Key:${it.key},Value:$it.value" //forEach,被變量的是Map.Entry
}
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（3）方法

• 括號是能夠忽略的

method1(2,3) //
method1 2,3 //可忽略括號，
def method1(int a,int b){
    println a+b
}
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• return 是能夠不寫的，最後一句代碼做爲其返回值

def method2(int a,int b){
    if(a>b){
        a //即return a;
    }else {
        b //即return b;
    }
}
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• 代碼塊/方法是能夠做爲參數傳遞的

//呆板寫法
nums.each({println it})

//格式化一些
nums.each({
    println it
})

//Groovy中，若是方法的最後一個參數是 閉包，則能夠放到方法外面
nums.each(){
    println it
}

//而後省略括號，則變成常見的樣式
nums.each{
    println it
}

//多參數調用
eachMap{k,v->
    println "$k is $v"
}
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• JavaBean,能夠很容易地訪問和修改屬性值，而不用經過getter/setter，因Groovy內部已幫咱們搞定好。

def Person p = new Person()
println "name is $p.name" //輸出null
p.name = "John" 
println "name is $p.name" //輸出John

class Person {
    private String name
}
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• 閉包委託 Groovy的閉包有thisObject、owner和delegate三個屬性，通常是thisObject>owner>delegate，但能夠修改delegate。通常指定delegate爲當前it，這樣就能夠在閉包內對該it進行配置，或調用其方法。

task delegate{
	doLast{
		person{
			name = "cap" //在閉包內對該it進行配置
			age = 20    //在閉包內對該it進行配置
			dumpPersion()  //在閉包內對該it調用其方法
		}
	}


}
def dumpPersion(){
	println "project delegate"
}


class Person{
	private String name
	private int age 

	def dumpPersion(){
		println "name:${name};age:${age}"
	}
}

def person(Closure<Person> closure){
	Person p = new Person()
	closure.delegate = p //設置委託
	closure.setResolveStrategy(Closure.DELEGATE_FIRST)//設置委託優先
	closure(p)
}
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Gradle 插件

一、Java Gradle 的sourceSets經常使用屬性

sourceSet，即源代碼集合（Android的buildTypes和這個相似），用來描述和管理源代碼和資源存放等功能。提供有sourceSets{}閉包放配置和生成sourceSet，如：

sourceSets{
    main{
        //在這裏能夠對main sourceSet進行配置
        
        java{
            srcDir 'src/java' //更改了java源代碼存放目錄，默認是 src/main/java
        }
        resources{
            srcDir 'src/resources' //更改了資源文件存放目錄，默認是 src/main/resources
        }
    }
    vip{
        //生成了新的 vip sourceSet
    }
}
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SourceSet經常使用屬性：

屬性名	類型	描述
name	String	只讀，如，main
java	SourceDirectorySet	該源集的java源文件
java.srcDirs	Set	該源集的java源文件所在目錄
resources	SourceDirectorySet	該源集的資源文件
resources.srcDirs	Set	該源集的資源文件的所在目錄
output.classesDir	File	該源集編譯後的class文件目錄
output.resourcesDir	File	編譯後生成的資源目錄
compileClassPath	FileCollection	編譯該源集時所需的classPath

二、Android Gradle插件分類和三個sourceSet

Android Gradle插件的分類是根據Anroid工程的屬性分類的，在Android中，有3類：

1. App應用工程插件id: com.android.application
2. Library庫工程插件id: com.android.library
3. Test測試工程插件id: com.android.test

注：src目錄下的androidTest，main，test分別是3個sourceSet，分別對應，Android單元測試代碼，Android app主代碼和資源，普通單元測試代碼。 在main中，特有AndroidManifest.xml和res這兩個Android特有的，用於描述Android App 配置和資源文件。