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iosswiftswift-dictionary

Displaying a randomised set of image and text from a dictionary in Swift

I'm trying to retrieve and display from a dictionary a randomised set of an image with its associated text on click of a button.

First, I tried having the image array and text array seperate and use Int(arc4random_uniform()) to randomly pick the elements from the array to display. It worked, BUT in doing so I need to make sure the image and its associated text are in the same position within their own array and I thought there must be better ways to structure the data by combining them into a multidimensional array or a dictionary. I end up using a dictionary, but got stuck don't know how to get the image and text to display.

See in the code below //THIS IS THE BIT I GOT STUCK AT. I don't know how to retrieve the image and its text from the dictionary.

I am not sure if it's ok to put the myImage and myText var in the dictionary and it seems a bit tedious to keep repeating 'myImage', 'myText' for each set as well.

@IBOutlet weak var myImage: UIImageView!
@IBOutlet weak var myText:  = UILabel()

var randomSet = [[myImage:"1-image", myText:"text for 1"], [myImage:"2-image", myText:"text for 2"], [myImage:"3-image", myText:"text for 3"], [myImage:"4-image", myText:"text for 4"], [myImage:"5-image", myText:"text for 5"]]

func randomiseSet (){
        let randomNumber:Int = Int(arc4random_uniform(5))
        //THIS IS THE BIT I GOT STUCK AT
        myImage.image = UIImage(named: randomSet[randomNumber])
        myText.text = randomSet[randomNumber]
        //END
    }

@IBAction func showRandomSet(_ sender: UIButton) {
        randomiseSet()
    }

I also tried instead of using myImage.image = .... myText.text = ....

return randomSet[[randomNumber]]

Both didn't work and showed 'Build Failed'

I have also investigated using CoreData but I'm a noob and that opens another can of worm for me regarding binary data for images vs using URL due to image size etc.

Any suggestion on what's the best way to fix the above is much appreciated. Thanks.

Solution

  • The problem is that the line myImage.image = UIImage(named: randomSet[randomNumber]) is wrong because randomSet[randomNumber] returns [String:String], not String. What you instead need to do is randomSet[randomNumber]["myImage"], which will return the string you want to initialize the UIImage.

    Also note: your dictionary's keys should be Strings in this case. Unless myImage and myText are declared as Strings elsewhere, your dictionary is set up incorrectly. Try changing your randomSet to [["myImage":"1-image", "myText":"text for 1"], ["myImage":"2-image", "myText":"text for 2"], ["myImage":"3-image", "myText":"text for 3"], ["myImage":"4-image", "myText":"text for 4"], ["myImage":"5-image", "myText":"text for 5"]]

    So, implementing the changes, your code should look something like this:

    @IBOutlet weak var myImage: UIImageView!
//Note this change from `@IBOutlet weak var myText:  = UILabel()`, which is incorrect
@IBOutlet weak var myText: UILabel!

var randomSet: [[String:String]] = [["myImage":"1-image", "myText":"text for 1"], ["myImage":"2-image", "myText":"text for 2"], ["myImage":"3-image", "myText":"text for 3"], ["myImage":"4-image", "myText":"text for 4"], ["myImage":"5-image", "myText":"text for 5"]]

func randomiseSet (){
    let randomNumber:Int = Int(arc4random_uniform(5))
    myImage.image = UIImage(named: randomSet[randomNumber]["myImage"]!)
    myText.text = randomSet[randomNumber]
}

@IBAction func showRandomSet(_ sender: UIButton) {
    randomiseSet()
}