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iOS Build a Weather App with Swift Simple Data Structures Bootstrapping the UI

Posted by Shuoqi Chen
Shuoqi Chen
1,948 Points

Error: not convertible to "StringLiteralConvertible"

My stormy app didn't work as what I expected: (Instead of showing me the temperature "80" from the library, it shows me the default value "90º" which I typed in manually), so I delete the if let statement and just use the let statement to test it out. The code looks like this:

let plistPath = NSBundle.mainBundle().pathForResource("CurrentWeather", ofType: "plist") let weatherDictionary = NSDictionary(contentsOfFile: "plistPath") let currentWeatherDictionary = weatherDictionary["currently"] as? [String: AnyObject]

When I do so, there's an compiler error showing me that the following code:

let currentWeatherDictionary = weatherDictionary["currently"] as? [String: AnyObject]

cannot be executed because [String: AnyObject] is not convertible to StringLiteralConvertible.

I cannot figure out the problem. Can you help me?

Shuoqi Chen
Shuoqi Chen
1,948 Points 
let plistPath = NSBundle.mainBundle().pathForResource("CurrentWeather", ofType: "plist")
let weatherDictionary = NSDictionary(contentsOfFile: "plistPath")
et currentWeatherDictionary = weatherDictionary["currently"] as? [String: AnyObject] // This is where the error appears.
```html

4 Answers

Shuoqi Chen
Shuoqi Chen
1,948 Points

Problem solved! So first I accidentally conjure up a pair of quotation marks around the variable plistPath. And Second, there's actually some very subtle differences when I get rid of the if let statement. Here are the codes that finally work around my problem (without if let statement)

let plistPath = NSBundle.mainBundle().pathForResource("CurrentWeather", ofType: "plist")
 let weatherDictionary = NSDictionary(contentsOfFile: plistPath!)
 let currentWeatherDictionary = weatherDictionary!["currently"] as? [String: AnyObject]

It seems that I have to unwrap the variable plistPath and weatherDictionary first to get the same result when using optional binding by if let statement. Great lesson for me!

Ramesh VJ
Ramesh VJ
2,201 Points
Ramesh VJ
Ramesh VJ
2,201 Points

even after doing it, I'm getting runtime error in

@IBOutlet weak var currentTemperatureLabel: UILabel?

I tried ! also like below

@IBOutlet weak var currentTemperatureLabel: UILabel!

please help

Shuoqi Chen
Shuoqi Chen
1,948 Points

Can you paste your code here? and the error message?

Ramesh VJ
Ramesh VJ
2,201 Points
Ramesh VJ
Ramesh VJ
2,201 Points

@IBOutlet weak var currentTemperatureLabel: UILabel!

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

     let plistPath = NSBundle.mainBundle().pathForResource("CurrentWeather", ofType: "plist")
    let weatherDictionary = NSDictionary(contentsOfFile: plistPath!)
    let currentWeatherDictionary = weatherDictionary!["currently"] as? [String: AnyObject]

       let currentWeather = CurrentWeather(weatherDictionary: currentWeatherDictionary!)

        currentTemperatureLabel!.text = "\(currentWeather.temperature)"

}

Initially I typed exactly whats in the video, I got Run Time Error, so I changed the code as said in this thread, even for this I'm getting Run Time Error.

(lldb)

aDecoder NSCoder 0x00007f8ed4843e00 0x00007f8ed4843e00 self Stormy.ViewController 0x00007f8ed2f3de60 0x00007f8ed2f3de60

I'm getting Thread 1 : breakpoint 1.5 on @IBOutlet weak var currentTemperatureLabel: UILabel!

Ramesh VJ
Ramesh VJ
2,201 Points
Ramesh VJ
Ramesh VJ
2,201 Points

when I tried it from the start following the video again, I didn't get any error. everything worked. thanks for the help