Android support library error after updating to 23.3.0

Question

I have been using android support v4 23.1.1 and recently tried to update it to 23.3.0 ( the latest one when this was asked) but I got the following error:

Answer 1

My orignal app.gradle had:

dependencies {
    // App dependencies
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.4.0' 

    // Testing-only dependencies
    androidTestCompile 'com.android.support.test:runner:0.3'
    androidTestCompile 'com.android.support.test:rules:0.3'
    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2'
}

which resulted in following error:
Error:Conflict with dependency 'com.android.support:support-annotations'. Resolved versions for app (23.4.0) and test app (22.2.0) differ. See http://g.co/androidstudio/app-test-app-conflict for details.

After reading the link suggested in error, I found theses lines:

When instrumentation tests are run, both the main APK and test APK share the same classpath. Gradle build will fail if the main APK and the test APK use the same library (e.g. Guava) but in different versions. If gradle didn't catch that, your app could behave differently during tests and during normal run (including crashing in one of the cases).

So I modified my app.gradle dependencies to:

dependencies {
    // App dependencies
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.4.0'

    // Testing-only dependencies
    androidTestCompile 'com.android.support:support-annotations:23.3.0'
    androidTestCompile 'com.android.support.test:runner:0.3'
    androidTestCompile 'com.android.support.test:rules:0.3'
    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2'
}

Even after the above change gradle was not happy :-(:
Error:Conflict with dependency 'com.android.support:support-annotations'. Resolved versions for app (23.4.0) and test app (23.3.0) differ. See http://g.co/androidstudio/app-test-app-conflict for details.

Change in test apk version was different! So I modified the version string as pasted below which worked for me:

(Nirvana)

dependencies {
    // App dependencies
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.4.0' // main APK

    // Testing-only dependencies
    androidTestCompile 'com.android.support:support-annotations:23.4.0' //test APK
    androidTestCompile 'com.android.support.test:runner:0.3'
    androidTestCompile 'com.android.support.test:rules:0.3'
    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2'
}