great stuff.
Giovanni Perrotta

Hello Giovanni,

The `context = this` was merely a way to pass the Context into an Object so that we could display the Toast properly. We could not use `this` instead because the Object in which the Toast was declared is not an instance of Context.

For what concerns the OnCompleted() event, it’s not mandatory to declare it (and more often than not, you don’t need to use it) but for the sake of completeness, we showed that you can know when an Observable finishes its emissions.