[Journey In App Creation]Post 3- Getting The Data

Lets get started. We have the design so lets start with that. But first, we need some music. For that, we turn to Spotify. I've been on a bit of a Avicii streak recently so lets continue with that.

_{Source: Spotify}

Now that we got that out of the way, lets go rename the ViewController to a more descriptive name and clean it up. We get this as a result:

We first need to connect the textField to the code. We do that with a IBOutlet. Lets also connect the submit button as an action so that upon touch it, we can get something to happen. To start, I just made pressing the button print out(I tried console.log() to get it to print at first, JS is affecting me) what was in the text field. Its as simple as print(nameTextField.text). Since that works, time to move on.

Lets think of the first case. If there isn't anything in the nameTextField. What do we do? Well, we need to warn the user. So lets add a label that will be hidden upon initial launch and (so far) will only show up if the text field is empty.

This will let us see if the the text field was empty or not(yes, swift doesn't need semicolons, or parentheses around the if statement):

let name = nameTextField.text
if name == ""
{
    print("No Name Entered")
    return
}

By returning out, we ensure that the code after that statement won't be executed if there is no name entered. We can work on handling that particular case later and replace the print("No Name Entered") with a visual handling of the error.

Now, a great song plays so we take a little break. If you haven't listened to Sunset Jesus, give it a listen. Click here to open it on Spotify.

Now we need to get data from an API. We can do everything locally and process it here, but because I don't want to, I'll be writing up some JS and making an API with that. I most likely won't share the process creating the API as this is a lot more focused on the mobile app part of it. If you want me to write how I made the (probably shitty) API, just leave a comment. There is a built in way to fetch data, but I'll be using Alamofire as its a lot easier(and cleaner looking). So lets install it. I'll be using Carthage as my dependency manager as I find it cleaner than CocoaPods. If you want to learn more about Carthage, you can click here.

Once you got it installed, and added to your project, you can import it with import Alamofire.

We can now make a request to the API(currently hosted on http://localhost:8080). It'll be as simple as making a get request. I made it as simple as adding /?userName to the url to get the data. So for example, to get data for me would be http://localhost:8080/?rishi556. So, lets do it. We write it as:

Alamofire.request("http://localhost:8080/?" + name, parameters: nil, headers: nil).responseJSON { response in
            print(response)
}

It would be a good idea to take the start of the url and make it its own variable so we can edit it easily for everywhere if we want to later on. But I'll do that later. But because the App transport securities aren't configured properly, it won't work. So we have to go to the info.plist and edit it to allow it. Lets fix it and rerun it.

If everything was done properly, we'll get some pieces of data back from the API.

_{I haven't yet written up the active posts part or the SP part so just gotta wait on that.}

But what if the name entered isn't a real name? Well, then it returns this message:

Also, don't worry about capitalization as the api server converts it to lowercase when processing through it.

In case we don't get any data back, we need to notify the user. We can tell that we didn't get any if response.value is set to nil. So we can check for that and notify the user and return out with this:

if response.value == nil
            {
                //TODO: Notify User That No Data Was Returned.
                print("There isn't any data returned.")
                return
            }

Now that we are are getting the data, lets simply parse it out and assign it to a few variables. Lets also convert them to a Swift type.

let vp = (responseDict["vp"] as! NSString).floatValue
let liquidSteem = (responseDict["liquidSteem"] as! NSString).floatValue
let savingSteem = (responseDict["savingSteem"] as! NSString).floatValue
let liquidSBD = (responseDict["liquidSBD"] as! NSString).floatValue
let savingSBD = (responseDict["savingSBD"] as! NSString).floatValue

Once I get the SP part and Posts part added in, we just have to assign them to a variable too. And I think we are good for today. Here's the entire code so far:

import UIKit
import Alamofire

class NameVC: UIViewController
{

    @IBOutlet weak var nameTextField : UITextField!
    
    override func viewDidLoad()
    {
       
    }
    
    @IBAction func submitButtonAction(_ sender: UIButton)
    {
        let name = nameTextField.text
        
        if name == ""
        {
            //TODO: Notify User That They Didn't Enter A Username
            print("No Name Entred")
            return
        }
        
        Alamofire.request("http://localhost:8080/?" + name!, parameters: nil, headers: nil).responseJSON { response in
            if response.value == nil
            {
                //TODO: Notify User That No Data Was Returned.
                print("There isn't any data returned.")
                return
            }
            
            let responseDict : [String: Any] = response.value as! [String : Any]
            print(responseDict)
            let message = responseDict["message"] as! String
            
            if message == "fail"
            {
                //TODO: Notify User That They Didn't Enter A Correct Username
                print("Username No Exist")
                return
            }
            
            let vp = (responseDict["vp"] as! NSString).floatValue
            let liquidSteem = (responseDict["liquidSteem"] as! NSString).floatValue
            let savingSteem = (responseDict["savingSteem"] as! NSString).floatValue
            let liquidSBD = (responseDict["liquidSBD"] as! NSString).floatValue
            let savingSBD = (responseDict["savingSBD"] as! NSString).floatValue
            
            print(vp, liquidSteem, savingSteem, liquidSBD, savingSBD)
                
            
        }
        
    }
    

}

Next time I'll be working on making the view look nicer and finishing up those TODOs. If you got any questions, throw them in the comments.

Now for the SBI giveaway. Lets make it fun, nothing to do with coding. This is more of a guessing game. Whats my favorite song in Avicii's album Stories(Hint: Its not Sunset Jesus)? All the songs in the album can be found here. First person to get it will get 1 SBI share.