How can I set the value of this variable? - ios

Question

I want to change the value of a UIImage view.
This is what I've got so far.
import UIKit
import Foundation
struct imageViews {
var Slope1ImageView: UIImage?
var slopeStatus = dataValues()
func setSlope1Image(slopeStatus1: Int) -> UIImage {
var image: String
switch slopeStatus1 {
case 0:
image = "NotWorkingStatus"
default:
image = "WorkingStatus"
}
var statusImage = UIImage(named: image)
return statusImage
}
}
This my setup.
I have a file which gets an object from Parse.
This will either be 0 or 1.
I then assign the 0 or the 1 to a variable in a struct.
In my code above I have created a instance of this struct.
I have then created a function which will take in a variable from my struct and check if it has the value of zero, it then sets the variable image to the respective image. If it doesn't it sets it to a different image.
How do I set the variable of Slope1ImageViews to the image selected by the function in this way.
Slope1ImageView = setSlope1Image(slopeStatus.SlopeStatus1)
each time I try I get an error along the lines of
cannot assign to "Slope1ImageView" in "self"
I'm at my wits end!
Any help would be greatly appreciated.

Answer 1

I think your problem is with Slope1ImageView. If the first letter is uppercased, Swift assumes you're referring to a class. Furthermore, you need to assign the local to either a variable or a constant. Structs should also have the first letter uppercased. Assuming everything else is set up correctly, you probably just need to do something like this.
struct ImageViews {
// existing code...
}
var instanceOfStruct = ImageViews()
var slope1imageView: UIImage = instanceOfStruct.setSlope1Image(slopeStatus.SlopeStatus1)

Answer 2

There's a lot going on here, I'll touch on some.
Declaration
You shouldn't be using a struct. Images are rather large objects in general and you don't want them to be copied across your app. They should remain reference types and be in a class. Structs/Classes should also be capitalized to adhere to common practice, while properties should be lower case. You also have your name as a plural which implies that it is an array, it shouldn't be this way. Also, don't name something imageView unless its an imageView. On that same line, don't name something image if it's a string. Also, don't prefix a function with set unless it sets something. Your function returns something, so a get prefix is probably better. I feel like you want to set the image within self, so let's do that. So first step is to change this:
struct imageViews {
var Slope1ImageView: UIImage?
var slopeStatus = dataValues()
func setSlope1Image(slopeStatus1: Int) -> UIImage {
var image: String
switch slopeStatus1 {
case 0:
image = "NotWorkingStatus"
default:
image = "WorkingStatus"
}
var statusImage = UIImage(named: image)
return statusImage
}
}
To this:
class SlopeStatus {
var slope1Image: UIImage?
var slopeStatus = dataValues()
func setSlope1Image(slopeStatus1: Int) {
var imageString: String
switch slopeStatus1 {
case 0:
image = "NotWorkingStatus"
default:
image = "WorkingStatus"
}
slope1Image = UIImage(named: image)
}
}
Assignment
You're trying to assign a UIImage to a Class with this:
Slope1ImageView = setSlope1Image(slopeStatus.SlopeStatus1)
With the changes above, it should probably be
var slopeStatusImageObject = SlopeStatus()
slopeStatusImageObject.setSlope1Image(slopeStatus.SlopeStatus1)