ViewPagerIndicator library with Android Studio

Android-ViewPagerIndicator is presented as an Android library project. A standalone JAR is not possible due to the theming capabilities offered by the indicator widgets. Therefore, to use this library with Android Studio and Gradle, there were some complications but I finally managed to get this external library working. So I wrote this small guide into how to get an external library such as ViewPagerIndicator, which has not been built with Gradle, to work in your project. I hope that will spare you  a couple of hours of struggling with different errors such as:

• UNEXPECTED TOP-LEVEL EXCEPTION: occurs when the external library set the same dependencies for both your project and the libraries.
• Manifest Merging Failed: occurs when the minimum SDK version of the library is different from the one set in your project.
• No resource found that matches the given name ‘@style/Theme.AppCompat.Light.DarkActionBar’: occurs when android.support.v7.appcompat library is missing.

My environment

• Android Studio (Preview) 0.6.1 Build #AI-135.1224218, built on June 12, 2014
• JRE: 1.7.0_51-b31 amd64
• ViewPagerIndicator Version 2.4.1 — 2012-09-11

Step by step

1. Create a new directory at the root of your project, name it “libraries” (case sensitive).
2. Download and extract the library ViewPagerIndicator; it has 2 subdirectories: library and sample.
3. Copy the library directory to the libraries directory of your project and rename it to avoid confusion. Here, I renamed it to viewpager_indicator.
   
4. Create a file at the root of the viewpager_indicator directory and name it build.grable. Here is a basic Gradle build file:

apply plugin: 'android-library'

android {
    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = ['src']
            resources.srcDirs = ['src']
            aidl.srcDirs = ['src']
            res.srcDirs = ['res']
            assets.srcDirs = ['assets']
        }
    }

    compileSdkVersion 19
    buildToolsVersion '19.1.0'
}

dependencies {
    compile 'com.android.support:support-v4:+'
    compile 'com.android.support:appcompat-v7:+'
}

These lines have to match the ones declared in your build.gradle of your application (located at: YourProject > app > src).

compileSdkVersion 19
buildToolsVersion '19.1.0'

Here I didn’t precise the versions of com.android.support:support-v4 and com.android.support:appcompat-v7 but you may need to do it to match the configuration of your project.
– com.android.support:support-v4 is used by both my application and ViewPagerIndicator library.
– com.android.support:appcompat-v7 is used by my application.
5. Modify the dependencies of the build.gradle of the application (located at: YourProject > app > src):

apply plugin: 'android'

android {
    compileSdkVersion 19
    buildToolsVersion '19.1.0'

    defaultConfig {
        minSdkVersion 7
        targetSdkVersion 19
        versionCode 1
        versionName '1.0'
    }

    buildTypes {
        release {
            runProguard false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
        }
    }

    productFlavors {
    }
}

dependencies {
    compile project(':libraries:viewpager_indicator')
}

The only library my application depends one is viewpager_indicator because the dependency com.android.support:support-v4 will be set for the library.
6. Modify the Gradle settings of your project to include the library. Here is my settings.gradle:
include ':libraries:viewpager_indicator', ':app'
7. Voila, BUILD SUCCESSFUL 🙂

In this sample, I only have 1 library which has the dependency com.android.support:support-v4 in common with my application. The solution is then setting this dependency for the library. But if you have more than 1 library, you have to set the common dependencies only for your application and remove them from the libraries.

Enjoy and may the Force be with you!