SwiftUI Tutorial - Scrumdinger - mysterious AVPlayer initialization syntax

I've been following the Scrumdinger tutorial and had close to no trouble understanding the concepts, supplementing myself with the Swift guide.

However, in the state and lifecycle lesson, exactly in the complete project, I've found confusing syntax that I cannot decipher with certainty.

private var player: AVPlayer { AVPlayer.sharedDingPlayer }

What does the closure after the AVPlayer type mean?

sharedDingPlayer is a static property extending AVPlayer, so my guess is that it's either some kind of casting to this exact type or assigning the static prop to the player property when it's available.

I would appreciate any help in clearing this out!

Up vote post of jordan-na-dzielni Down vote post of jordan-na-dzielni
176 views
Posted by
jordan-na-dzielni
Reply
Add a Comment

Accepted Reply 

private var player: AVPlayer { AVPlayer.sharedDingPlayer }

This is how a computed var is defined.

It is equivalent to:

private var player: AVPlayer { 
  get {
     return AVPlayer.sharedDingPlayer
   }
}
Posted by
Claude31
Up vote reply of Claude31 Down vote reply of Claude31
Post marked as solved

  • You are of course right! This one-liner even confused me, though I used many computed vars in Swift already. ;-)

    —
    Dirk-FU

  • Thank you for the elaborate example! I'm just starting to get used to all the shortcuts that Swift has to offer.

    —
    jordan-na-dzielni

  • As a side note - correct me if I'm wrong, but isn't including the type information redundant, since Swift could infer it from the declaration?

    —
    jordan-na-dzielni

Replies

I can not find your quoted code private var player: AVPlayer { AVPlayer.sharedDingPlayer } in the Project Files.

Did you mean private var player: AVPlayer = { AVPlayer.sharedDingPlayer }() ?

This initialises the playervariable of Type AVPlayer with the result of the provided closure, which simply returns AVPlayer.sharedDingPlayer while leaving out the not needed return statement.

Posted by
Dirk-FU
Up vote reply of Dirk-FU Down vote reply of Dirk-FU

  • It was precisely the line I included. It is to be found in the MeetingView.swift file, line 12.

    —
    jordan-na-dzielni
Add a Comment 
private var player: AVPlayer { AVPlayer.sharedDingPlayer }

This is how a computed var is defined.

It is equivalent to:

private var player: AVPlayer { 
  get {
     return AVPlayer.sharedDingPlayer
   }
}
Posted by
Claude31
Up vote reply of Claude31 Down vote reply of Claude31
Post marked as solved

  • You are of course right! This one-liner even confused me, though I used many computed vars in Swift already. ;-)

    —
    Dirk-FU

  • Thank you for the elaborate example! I'm just starting to get used to all the shortcuts that Swift has to offer.

    —
    jordan-na-dzielni

  • As a side note - correct me if I'm wrong, but isn't including the type information redundant, since Swift could infer it from the declaration?

    —
    jordan-na-dzielni