设置属性

COMPILE_SDK_VERSION = 26
BUILD_TOOLS_VERSION = 26.0.0
MIN_SDK_VERSION = 19
TARGET_SDK_VERSION = 26
VERSION_CODE = 1
VERSION_NAME = 1.0

build.gradle中使用

android {
    compileSdkVersion COMPILE_SDK_VERSION as int
    buildToolsVersion BUILD_TOOLS_VERSION
    defaultConfig {
        applicationId "com.xtao.simpledemo"
        minSdkVersion MIN_SDK_VERSION as int
        targetSdkVersion TARGET_SDK_VERSION as int
        versionCode VERSION_CODE as int
        versionName VERSION_NAME
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
            buildConfigField("int", "TARGET_SDK_VERSION", "${TARGET_SDK_VERSION}")
        }
        debug {
            buildConfigField("int", "TARGET_SDK_VERSION", "${TARGET_SDK_VERSION}")
            resValue("string", "VERSION_NAME", "${VERSION_NAME}")
        }
    }
}

Java中调用

build.gradle中设置buildConfigField("int", "TARGET_SDK_VERSION", "${TARGET_SDK_VERSION}")
依次为：参数类型，参数名，参数值

int targetSDKVersion = BuildConfig.TARGET_SDK_VERSION;

XML中调用

build.gradle中设置resValue("string", "VERSION_NAME", "${VERSION_NAME}")
依次为：参数类型，参数名，参数值

<TextView
    android:id="@+id/textView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/VERSION_NAME"/>