What is the property block declaration equivalent in swift of the following block property?

Question

In Objective-C I do this:

@property (nonatomic, copy) void(^completion)(MyObject * obj);

What is the correct way to do this in swift?

possible duplicate of [swift : Closure declaration as like block declaration](http://stackoverflow.com/questions/24133797/swift-closure-declaration-as-like-block-declaration) — Martin R, Jun 30 '14 at 17:03
I've looked at that answer, I wasn't able to understand how to apply the solution given to this specific case — zumzum, Jun 30 '14 at 17:21
Is this how I could do it in Swift? var completion = { (obj: MyObject) -> Void in } — zumzum, Jun 30 '14 at 17:39
The other question is slightly different (not about properties), therefore I have removed my closing vote. — Martin R, Jun 30 '14 at 18:09

score 45 · Accepted Answer · answered Jun 30 '14 at 18:07

45

The corresponding closure property would be declared as

class MyClass {
     var completion : ((MyObject) -> Void)? // or ...! for an implicitly unwrapped optional
}

You can set the property like

completion = {
    (obj : MyObject) -> Void in
    // do something with obj ...
}

which can be shortened (due to the automatic type inference) to

completion = {
    obj in
    // do something with obj ...
}

answered Jun 30 '14 at 18:07

Martin R

1

we dont have to worry about the copy flag anymore? – Just a coder Jul 14 '16 at 19:49
2

@JTAppleCalendarforiOSSwift: No, the Swift compiler handles that automatically, to the best of my knowledge. – Martin R Jul 14 '16 at 19:57

1 Answers1