Daily Learnings

Starting android emulator using commandline

Emulator can be started using command line using:

emulator -avd <name>

Automatic publishing apk to Google Play Store Developer Console using Jenkins

Jenkins plugins:

Google Play Publishing plugins (only works on Jenkins version > 1.6.09)

Jenkins Build job

Separate build job for each flavor of apk
Create Free style build job in jenkins as described here.

Configure Service Account on Google Play Store as shown here.

Android Testing using ATSL (Android Testing Support Library)

Running instrumented unit tests
Instrumented unit tests are important when a functionality can't be tested using mock objects.

Tools used
AndroidJunitRunner is used to run such tests.

Configuring build.gradle

defaultConfig {
applicationId "appId" minSdkVersion 17 targetSdkVersion 23 versionCode 1
versionName "1.1"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"}

Dependencies

dependencies {
compile 'com.android.support:support-annotations:23.0.1' compile 'com.android.support:appcompat-v7:23.0.1'

androidTestCompile 'junit:junit:4.12' androidTestCompile 'com.android.support:support-annotations:23.0.1' androidTestCompile 'com.android.support.test:runner:0.4.1' androidTestCompile 'com.android.support.test:rules:0.4.1'
}

Running Instrument tests:

gradlew connectedAndroidTest

Useful links:

How to access build version from build.gradle from Java class

Its available in BuildConfig.java.

So simply access version name like this:

BuildConfig.VERSION_NAME

And Version code could be accessed like this:

BuildConfig.VERSION_CODE

How to publish artifacts (Android Library in "aar" format) to Maven repo from Android Studio gradle

This post shows build.gradle configuration to be able to push artifacts to local Maven repo. I've taken Android library in its "aar" format as artifact for example.

First add "maven-publish" plugin to enable publishing artifacts from build.gradle:

apply plugin: 'maven-publish'

Don't forget to add local maven repo:

repositories {
    mavenLocal()
}

Add publishing block now:

publishing {
    publications {
        mavenJava(MavenPublication) {
            groupId <GROUP_ID>
            artifactId <ARTIFACT_ID>
            version <currentVersion>

            artifacts = ["${buildDir}/outputs/aar/<your_android_library>.aar"]
        }
    }
}

How to create annotated Git tags

Annotated Git tags keep the information of related with tag and permanent in nature. It can be created using this command:

git tag -a <tagname>

An already existing tag can be modified using flag "-f" like this:

git tag -a -f <existing_tag_name>

A specific tag can be pushed to remote like this:

git push origin <tagname>

Deleting tags:

Deleting remote tag:

git push origin :<tagname> OR git push --delete origin <tagname>

Deleting local tag

git tag -d <tagname>

General guidelines:

git push where-to-push source-refs:destination-refs
git push <remote> <local-branch>:<remote-branch>
git push origin refs/head/master:refs/heads/master
git push origin master:master

How to change author for a GIT commit

First fix up the author details in .git/config file for the given repo by adding this block

[user]

name = <new name>
email = <new email>

Now execute following command to amend the commit:

git commit --amend --reset-author