google play - How to change Android version and code version number?

How to change Android version and code version number Android Studio? I want to change apk file (app) on Google Play and I need to change Android version and code version number. I tried with this in AndroidManifest.xml file in Android Studio:

package="com.bestsoftcorporation.circle.app"
android:versionCode="101"
android:versionName="2.0">

But it does not work. When I tried to publish it on Google Play it display that I must to change Android version name and code.

Answer

Go in the build.gradle and set the version code and name inside the defaultConfig element

defaultConfig {
    minSdkVersion 9
    targetSdkVersion 19
    versionCode 1

    versionName "1.0"
}