Sign up for a feature that provides an observable exclusively within an if statement

There is an if clause in my code that checks for the presence of the cordova object in the window global object. If cordova is present, it will make a http request and return the default angular 2 http observable.

If the application is in a web context where cordova does not exist, the function should not do anything.

However, in order to subscribe to the observable, I need to ensure I am returning an observable or else I will encounter a 'can't subscribe to null' error. Currently, I am using Observable.empty() as a solution,

but I wonder if there is a safer or more elegant approach. Thank you!

public init():Observable<Response>{
  if(window.cordova){
    return this.http.get(...)
  } else {
    return Observable.empty()
  }
}

This is the code snippet, and I noticed that I need to change something to make it work... Is there a way to return Observable instead?

Answer №1

It seems like there's some confusion about the issue at hand. :)

return Observable.of(null); - Is this what you're looking for?

return Observable.of(undefined); - Could this be the solution you need?

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