Swift - enum with button.tag? - objective-c

Question

i have this code in ObjC
and i want or trying to convert it to swift
typedef NS_ENUM(NSInteger, BB3Photo) {
kirkenType = 10 ,
festenType = 20 ,
praestType = 30
};
#property (nonatomic, assign) BB3Photo selectedPhotoType;
- (IBAction)changeImage:(id)sender {
if ([sender isKindOfClass:[UIButton class]]) {
UIButton *button = sender;
_selectedPhotoType = button.tag;
}
UIActionSheet *sheet = [[UIActionSheet alloc] initWithTitle:#"Vælg Billed"
delegate:self
cancelButtonTitle:nil
destructiveButtonTitle:nil
otherButtonTitles:#"Vælg fra Biblioteket", #"Vælg Kamera", nil];
sheet.actionSheetStyle = UIActionSheetStyleDefault;
[sheet showInView:[self.view window]];
}
here's what i have made from it
enum BBPhoto1: Int {
case kommunen = 10
case sagsbehandler = 20
case festen = 30
}
var selectedPhoto = BBPhoto1.self
#IBAction func changeImage(sender: AnyObject){
if sender .isKindOfClass(UIButton){
let button: UIButton = sender as UIButton
selectedPHoto = (sender as UIButton).tag as BBPhoto1 // doesent work "cannot assign that result as expression"
selectedPHoto = button.tag // doesnt work either "cannot assign that result as expression"
self.selectedPhoto = BBPhoto1.fromRaw((sender as UIButton).tag) // nope "cannot convert the expressions type () to type UIButton"
}
}
i want to be able to have a switch statement with button tags to the same funktion but different in the code

Answer 1

You want to use the tag as the raw value of your BBPhoto1 enum. You can do this with conditional unwrapping:
#IBAction func changeImage(sender: AnyObject){
if let button = sender as UIButton {
if let photoType = BBPhoto1.fromRaw(button.tag) {
self.selectedPhoto = photoType
}
}
}
There's also a problem with the declaration of your selectedPhoto property. It should be:
var selectedPhoto: BBPhoto1?
The way you have it now it doesn't hold a BBPhoto1 value, but instead the type of BBPhoto1 itself.
Note that the fromRaw syntax has changed to an initializer in Xcode 6.1:
#IBAction func changeImage(sender: AnyObject){
if let button = sender as UIButton {
if let photoType = BBPhoto1(rawValue: button.tag) {
self.selectedPhoto = photoType
}
}
}

Answer 2

How about:
#IBAction func changeImage(sender: AnyObject){
if sender .isKindOfClass(UIButton){
let button: UIButton = sender as UIButton
selectedPHoto = BBPhoto1.fromRaw(button.tag)
}
}
or (shorter):
#IBAction func changeImage(sender: UIButton){
selectedPHoto = BBPhoto1.fromRaw(sender.tag)
}

Answer 3

Ok, Not the same code; as in validating a text field, but the same principle in Swift 4, iOS 11, xCode 9.2.
enum SFT: Int {
case StudentNameFieldTag
case StudentIDFieldTag
case StudentClassFieldTag
case ChallengeCodeFieldTag
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
if textField.tag == SFT.StudentClassFieldTag.rawValue {
let whitespaceSet = CharacterSet.whitespaces
if let _ = string.rangeOfCharacter(from: whitespaceSet) {
return false
} else {
return true
}
}
return true
}

Answer 4

The fromRaw() method returns an optional, so you have to declare your property as optional:
var selectedPHoto: BBPhoto1?
and use this code:
self.selectedPhoto = BBPhoto1.fromRaw((sender as UIButton).tag)
Alternatively, you can unwrap the fromRaw return value:
self.selectedPHoto = BBPhoto1.fromRaw((sender as UIButton).tag)!
Note however that in this case, if the raw value doesn't map to an enum, a runtime exception will be raised.