lesson3.4_sequenceOf

Lesson 3.4: sequenceOf

Problem statement

Write an app which spits out three "hello" messages to the debugging console, using func sequenceOf.

Problem project

You can use the project in the problem folder of this repo as a starting point.

Note: I have omitted the Carthage folder from the problem project, because it includes large binary files. In order to use the this project, you will need to run carthage update --platform iOS.

Solution

ViewController.swift:

import UIKit
import RxSwift
import RxCocoa

class TripleHelloGenerator
{
    class func generate() -> Observable<String>
    {
        return sequenceOf("hello","hello","hello")
    }
}

class ViewController: UIViewController {

    let disposeBag = DisposeBag()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        TripleHelloGenerator.generate().subscribeNext { (s) -> Void in
            debugPrint(s)
        }.addDisposableTo(disposeBag)
    }
}

Discussion:

Here, we use func sequenceOf, to generate only three "hello" messages:

Start up the app and verify that you see three "hello" messages in the console:

"hello"
"hello"
"hello"

New concepts to explore

• Open up RxExample.xcodeproj.
  • Take a look at func sequenceOf in Observable+Creation.swift

Solution project

My solution is included in the solution folder of this repo.

Note: I have omitted the Carthage folder from the solution project, because it includes large binary files. In order to run the this project, you will need to run carthage update --platform iOS.