AndroidStudio ClassNotFound gradle

Question

After a couple of hours, I finally got my app to build. Using gradlew, it builds using two submodules.

Whenever I install the result to my phone, it automatically throw an UndefinedClass error on the first created class (Activity)

build.gradle

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.4'
    }
}
apply plugin: 'android'

dependencies {
    compile files('libs/android-support-v4.jar')
    compile files('libs/crittercism_v3_0_3_sdkonly.jar')
    compile project(':libraries:slidingmenu')
    compile project(':libraries:actionbarsherlock')
}

android {
    compileSdkVersion 17
    buildToolsVersion "17.0.0"

    defaultConfig {
        minSdkVersion 7
        targetSdkVersion 16
    }
}

An settings.gradle

include 'libraries:actionbarsherlock', ':libraries:slidingmenu', ':NewApp'

I'm kind of at lost, it's building and all now but it apparently doesn't add the class to the package..

Answer 1

I've migrated my android app project for this purpose and it works. This is how my build looks like:

buildscript {
    repositories {
        mavenCentral()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:0.4'
    }
}

apply plugin: 'android'
apply plugin: 'eclipse'

repositories {
    mavenLocal()
    mavenCentral()
}

dependencies {
    compile 'com.google.guava:guava:14.0.1'
    compile 'com.google.code.gson:gson:2.2.4'
    compile 'commons-io:commons-io:2.4'
    compile 'pepuch:java-socket-server:1.0-SNAPSHOT'
    compile 'pepuch:multiplayergame-socket-server:1.0-SNAPSHOT'
}

android {
    compileSdkVersion 10
    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = ['src']

            resources.srcDirs = ['src']
            aild.srcDirs = ['src']

            renderscript.srcDirs = ['src']

            res.srcDirs = ['res']
            assets.srcDirs = ['assets']

        }


        instrumentTest.setRoot('tests')
    }
}

I haven't integrate it with any IDE but after I run gradle installDebug it generated *.apk on my phone which I installed. BTW I didn't change project structure but saved old directory structure.

Answer 2

Having to get it work with Android studio / Gradle isn't quite straightforward yet. I have to say that how it works is still quite messy but I finally got it to work after reading many answers.

If you have a project that has these dependencies:

• App depends on (Module1, Module2)

• Module1 depends on (Module2)

• Open the SDK manager and install the Google repository and Android support repository

• To make things simpler, move files in a structure such as Gradle expect it to be. (I can't tell if other structure will mess up with android plugins)
• Add an empty application inside each android library manifest.

The package, uses-sdk and empty application is the strict minimum for a android-library:

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.example.mymodule">
    <uses-sdk android:minSdkVersion="7" android:targetSdkVersion="16"/>
    <application />
</manifest>

The modules have this structure

• Module/build (where things get built)
• Module/src/main/java (the actual code)
• Module/src/main/res (resources layout and so on)
• Module/src/main/AndroidManifest.xml
• Module/build.gradle (our gradle config)

My first module as this build.gradle file

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.4'
    } } apply plugin: 'android-library'

repositories {
    mavenLocal()
    mavenCentral() }

dependencies {
    compile 'com.android.support:support-v4:13.0.0'
    compile project(':SecondModule') }

android {
    compileSdkVersion 17
    buildToolsVersion "17.0.0"

    defaultConfig {
        minSdkVersion 7
        targetSdkVersion 16
    }
}

Note that the module depens on project(:SecondModule) This means that at the root of the project is located SecondModule in which there is also a build.gradle file.

The SecondModule build.gradle look like this.

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.4'
    }
}
apply plugin: 'android-library'

repositories {
    mavenLocal()
    mavenCentral()
}

dependencies {
    compile 'com.android.support:support-v4:13.0.0'
}

android {
    compileSdkVersion 17
    buildToolsVersion "17.0.0"

    defaultConfig {
        minSdkVersion 7
        targetSdkVersion 16
    }
}

The second module doesn't depend on anything except android support . Note that in both project, the build is using mavenLocal() and mavenCentral() for building and not just the buildscript. The difference with the default android-library build.gradle file is that here, we are loading com.android.support:support-v4:13.0.0 from maven instead of a jar file. So we can peacefully add the dependency in each module without fearing that gradle will append it n times. For that to work, you have to install google repository and the android support repository.

The MainApp gradle file look like this:

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.4'
    }
}
apply plugin: 'android'

repositories {
    mavenLocal()
    mavenCentral()
}

dependencies {
    compile 'com.android.support:support-v4:13.0.0'
    compile project(':MyModule')
    compile project(':SecondModule')
}

android {
    compileSdkVersion 17
    buildToolsVersion "17.0.0"

    defaultConfig {
        minSdkVersion 7
        targetSdkVersion 16
    }
}

This file is applying the android plugin instead of the android-library plugin. If everything is fine, it should compile just well and run. Also since the project happens to be in development, make sure you have the latest version installed and it's possible that in the future this answer gets pointless.

Make sure that you never use the android support jar, but instead use the maven repository. The downside is that it may takes a while to compile but it will just work.