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iOS

Posted by Matt Carlson
Matt Carlson
1,281 Points

There is no Swift Reference for the NSURL class

Would anybody mind explaining the syntax to me from the NSURL Class reference in swift https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSURL_Class/index.html

I am attempting to transfer this project to swift https://robots.thoughtbot.com/streaming-audio-to-multiple-listeners-via-ios-multipeer-connectivity and I need some help with this section

NSURL *url = [myMediaItem valueForProperty:MPMediaItemPropertyAssetURL];
AVURLAsset *asset = [AVURLAsset URLAssetWithURL:url options:nil];
AVAssetReader *assetReader = [AVAssetReader assetReaderWithAsset:asset error:nil];
AVAssetReaderTrackOutput *assetOutput = [AVAssetReaderTrackOutput assetReaderTrackOutputWithTrack:asset.tracks[0] outputSettings:nil];

[self.assetReader addOutput:self.assetOutput];
[self.assetReader startReading];

What would the swift equivalent of this snippet be?

1 Answer

Michael Hulet
Michael Hulet
47,913 Points

  1. You're looking at the Mac Developer Library. Here's the equivalent for iOS.

  2. If you look at the top right-ish center of the page, you should be able to see where you can select which language you want to view it in. Your choices are Objective-C, Swift, or both.

  3. Here's the equivalent code in Swift:

let url = myMediaItem.valueForProperty(MPMediaItemPropertyAssetURL)
let asset = AVURLAsset.URLAssetWithURL(url, options: nil)
let assetReader = AVAssetReader.assetReaderWithAsset(asset, error: nil)
let assetOutput = AVAssetReaderTrackOutput.assetReaderTrackOutputWithTrack(asset.tracks[0], outputSettings: nil)

self.assetReader.addOutput(self.assetOutput)
self.assetReader.startReading()

I wrote that code off the top of my head without testing it, so I can't guarantee it'll work (though I think it will). If it doesn't, it'll be very close, and will only require a couple quick syntax changes that Xcode should be able to fix for you (but I think it'll work)

Matt Carlson
Matt Carlson
1,281 Points

So I am getting errors everywhere that just don see to make sense, such as view controller.type does not have a member called url, asset, assetreader, and assetoutput, how do I solve this, as they are obviously being declared right there.

Michael Hulet
Michael Hulet
47,913 Points

Could you post all the code in the relevant file here?

Matt Carlson
Matt Carlson
1,281 Points

Nevermind I fixed the error, I was attempting to access the variables within the class and not a specific function, however I am receiving this error Cannot invoke 'URLAssetWithURL' with an argument list of type '(Anyobject!, options: nil)' in this spot 

    var asset = AVURLAsset().URLAssetWithURL(url, options: nil)