update/change array value (swift)

Question

Data Model

class dataImage {
    var userId: String
    var value: Double
    var photo: UIImage?
    var croppedPhoto: UIImage?

init(userId:String, value: Double, photo: UIImage?, croppedPhoto: UIImage?){
    self.userId = userId
    self.value = value
    self.photo = photo
    self.photo = croppedPhoto
   }

}

View Controller

var photos = [DKAsset]() //image source
var datas = [dataImage]()

var counter = 0
    for asset in photos{
        asset.fetchOriginalImageWithCompleteBlock({ image, info in // move image from photos to datas

            let images = image
            let data1 = dataImage(userId: "img\(counter+1)", value: 1.0, photo: images, croppedPhoto: images)
            self.datas += [data1]
            counter++

        })
    }

from that code, let's say i have 5 datas:

 - dataImage(userId: "img1", value: 1.0, photo: images, croppedPhoto:
   images)
 - dataImage(userId: "img2", value: 1.0, photo: images, croppedPhoto:
   images)
 - dataImage(userId: "img3", value: 1.0, photo: images, **croppedPhoto:
   images**)
 - dataImage(userId: "img4", value: 1.0, photo: images, croppedPhoto:
   images)
 - dataImage(userId: "img5", value: 1.0, photo: images, croppedPhoto:
   images)

How to change/update img3's croppedImage value?

Answer 1

self.datas[2] = dataImage(userId: "img6", value: 1.0, photo: images, croppedPhoto:  images)

This will replace the 3rd object in the array with a new one.

or

self.datas[2].value = 2.0

This will change the value of the dataImage object with userId "img3".

Does this answer your question?

If you need to search for a specific value in userId, then you are far better of with a dictionary (associated array) rather than an (indexed) array.

var datas = [String, dataImage]()
...
self.datas["img\(counter+1)"] = ...

And you access it the same way.

self.datas["img3"].value = 2.0

And please rename the class imageData into ImageData. Class names start with capitals.