How do I import android packages into new Android module?

Question

I'm new to Android programming and new to Studio (0.4.4). For the first time, I found a class I wanted to incorporate into my project. Per other SO advice here, I created a new module by the same name, then replaced the Java template with the new class. So far so good.

Unfortunately, while it could find and import the java.* classes, it cannot find and import any of the android.* classes, specifically android.os.SystemClock and android.util.Log. (e.g., "Cannot resolve symbol 'X'") What steps do I need to take so that they can be found and imported? Thanks for any help.

Updated build.gradle:

apply plugin: 'java'

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:+'
}

Answer 1

If you want to use Android classes in a module, it needs to be an Android module. The build.gradle file needs to specify:

apply plugin: 'com.android.library'

And you may also need:

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.8.+'
    }
}

though newer projects are built from a template that includes this in the top-level build.gradle file and it's not necessary to specify it again below; try without and see if it complains or not.

In any event, with an android-library module type, you'll need an AndroidManfiest.xml file and the associated trappings of an Android project -- resource directories and the like. This is probably what you want -- that way if your library has resources or additions to the manifest file, they will get properly merged at runtime.