Return type of UIImage in Swift [closed] - objective-c

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I have a function which returns image if condition is satisfied else it returns nil
- (UIImage *)getProfilePic{
if (doc.userProperties != nil) {
UIImage *image = [UIImage imageNamed:#"placeholder.png"];
return image;
}
else {
return nil;
}
}
I want to convert this is in swift. I have tried this but it shows error while returning nil and also it crashes by showing error as unwrapping nil.
func getProfilePic(){
var image : UIImage?
if doc!.userProperties != nil {
image = UIImage(named: "placeholder.png")!
return image!
}
else {
return nil
}
}
at "return nil" line it shows nil is not compatible with return type ' uiimage'

Answer 1

func getProfilePic(){
var image : UIImage?
if doc!.userProperties != nil {
image = UIImage(named: "placeholder.png")!
return image!
}
else {
return nil
}
}
Right, so there are a few problems here. First, your code doesn't have a return type. If we ignore the body of your method and look just at the signature, the Objective-C equivalent would look like this:
- (void)getProfilePic;
So Swift & Objective-C would be complaining about the same thing here: what you're trying to return and the declared return type of the method do not match.
In case it's helpful since you seem perhaps more familiar with Objective-C than Swift, here's what your Swift method would look like if we translated it back into Objective-C:
- (void)getProfilePic {
UIImage *image;
if (doc.userProperties) {
image = UIImage(named: #"placeholder.png");
return image;
}
else {
return nil;
}
}
And again, this would generate the same or similar compile time warnings or errors, because the return type does not match the method signature. But Objective-C would not crash for unwrapping nil (but Swift will).
What you're actually trying to return is a UIImage?, so we need to update our method signature.
func getProfilePic() -> UIImage? {
if doc?.userProperties != nil {
return UIImage(named: "placeholder.png")
}
return nil
}
Assuming that userProperties holds perhaps a URL to an image you want to download or maybe the image itself, in the future we're going to want a slightly different construct... something more like this:
func getProfilePic() -> UIImage? {
guard let userProperties = doc?.userProperties else {
return nil
}
// extract the image from userProperties and return it
}

Answer 2

Try this code sample :
func getProfilePic() -> UIImage? {
let imageName = "placeholder.png"
var image: UIImage?
if (doc.userProperties != nil) {
image = UIImage(named: imageName)
}
return image
}