Setting Up RxJava

build.gradle(Module:app)

dependencies { 
... 
   // RxJava 
   implementation "io.reactivex.rxjava2:rxjava:$rxjava_version" 

   // RxAndroid 
   implementation "io.reactivex.rxjava2:rxandroid:$rxandroid_version" 
...
}

build.gradle

ext.rxjava_version = "2.1.2" 
ext.rxandroid_version = '2.0.1'