Build using Gradle

There are two types of Build.gradle file. In this time we often use which is located in app folder.

Build Variant Variables

If you want to change variables depend on build type. Declare buildTypes

android {
    buildTypes {
        debug{    // Build Variante Type
            buildConfigField("String" /* Variable Type */, "MYURL" /* Variable Name */, "\"test.seoul.go.kr\"" /* Variable Value */ )
        }
        release {
            buildConfigField("String", "MYURL", "\"seoul.go.kr\"")
            /* Delcare for Release */
            signingConfig signingConfigs.release
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
        debug2{
        
        }
    }
}

And then you can use simply BuildConfig class static variable.

BuildConfig.APPLICATION_ID
BuildConfig.MYURL

Release APK Run,Compile and Generate

Before release version compiled you need belows.

keystore
signingConfigs in build.gradle

Keystore

menu > build > generate signed key
If you don't have key store, make key store(It is needed one and once)

2.1 If you have key store, just type key store password
Input key alias, key password. It's belong to Project

3.1 Finish all above instruction, you have 'app-release.apk' in the app folder
Don't forget Sync Gradle

Declare signingConfigs

android {
    /* Declare Directly */
    signingConfigs {
        release{
            storeFile file("../../keystore/keystore.jks")   // Keystore Path
            storePassword "************"
            keyAlias "testKey"
            keyPassword "123456"
        }
    }
}

But this way has insecure problem. If you share this project to repository. Your key store information has exposed. It can be solved using move that information to gradle.properties and .gitignore

Note : It is ignored git repositry, you have to set gradle.properties manually. unless it can't be worked properly.

Move information to gradle.properties

# Project-wide Gradle settings.

# IDE (e.g. Android Studio) users:
# Gradle settings configured through the IDE *will override*
# any settings specified in this file.

# For more details on how to configure your build environment visit
# http://www.gradle.org/docs/current/userguide/build_environment.html

# Specifies the JVM arguments used for the daemon process.
# The setting is particularly useful for tweaking memory settings.
org.gradle.jvmargs=-Xmx1536m

# When configured, Gradle will run in incubating parallel mode.
# This option should only be used with decoupled projects. More details, visit
# http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
# org.gradle.parallel=true

storePw = *********
keyId = testKey
keyPw = 123456

Change delcare in siningConfigs File

    storePassword storePw
    keyAlias keyId
    keyPassword keyPw

add 'gradle.properties' file to '.gitignore'
```
    /gradle.properties
```

Compile,Run and Generate APK