How to pass multiple enum values as a function parameter

Question

How would I do the following - passing two NSStringDrawing options as a function parameter in swift:

CGRect boundingRect = [string boundingRectWithSize:CGSiz         


        

Answer 1

Swift supports C's bitwise OR operator, but the enum's values are now in a specific scope instead of simply being global symbols:

let boundingRect = "fpp".boundingRectWithSize(CGSizeMake(280.0, CGFloat.max),
    options:NSStringDrawingOptions.UsesLineFragmentOrigin | NSStringDrawingOptions.UsesFontLeading,
    attributes:nil, context:nil)

Answer 2

Edit: In Swift 3.0:

let options: NSStringDrawingOptions = [.usesLineFragmentOrigin, .usesFontLeading]

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Edit: This is how you would use the options enum in Swift 2.0:

let options: NSStringDrawingOptions = [.UsesLineFragmentOrigin, .UsesFontLeading]

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Edit: The issue has been resolved in iOS 8.3 SDK Beta 1 (12F5027d):

Modified NSStringDrawingOptions [struct]

• From: enum NSStringDrawingOptions : Int
• To: struct NSStringDrawingOptions : RawOptionSetType

You can now write:

let options : NSStringDrawingOptions = .UsesLineFragmentOrigin | .UsesFontLeading

---

After some research and and @Anton Tcholakov's "comment":

1. If you're targeting OS X 10.10, this is as simple way to do it:

   let size = CGSize(width: 280, height: Int.max)
   let options : NSStringDrawingOptions = .UsesLineFragmentOrigin | .UsesFontLeading
   
   let boundingRect = string.bridgeToObjectiveC().boundingRectWithSize(size, options: options, attributes: attributes, context: nil)
   

2. However, in iOS 8 SDK (in the current seed), there's a bug, where NSStringDrawingOptions is ported to Swift as enum : Int, instead of struct : RawOptionSet. You should send a bug report to Apple describing this serious problem.

Answer 3

In Swift 2.1 we may use,

calculatedRect = (text as NSString).boundingRectWithSize(bounds.size, options: NSStringDrawingOptions([.UsesLineFragmentOrigin, .UsesFontLeading]), attributes: [NSFontAttributeName : font], context: nil)

to pass multiple enum values for a parameter.

Answer 4

Can't seem to comment to akashivskyy's post (not got 50+ reputation), but this seems to work on my end:

import Cocoa

let drawingOpts : NSStringDrawingOptions = .UsesLineFragmentOrigin | .UsesFontLeading
let boundingRect = "test".bridgeToObjectiveC().boundingRectWithSize(CGSize(width: 280, height: Int.max), options: drawingOpts, attributes: nil)

Also if I Cmd+click NSStringDrawingOptions I see it as inheriting from RawOptionSet.

Answer 5

In swift 4.0+ we can pass multiple options like this, its working for me

let options = NSStringDrawingOptions(rawValue: NSStringDrawingOptions.usesLineFragmentOrigin.rawValue | NSStringDrawingOptions.usesFontLeading.rawValue)

let boundingRect = string._bridgeToObjectiveC().boundingRect(with: CGSize(width: 280, height: Int.max), options: options, attributes: [NSAttributedString.Key.font: UIFont.systemFont(ofSize: 19.0)], context: nil)

Answer 6

Updated answer for Xcode 6.3:

in Xcode 6.3 Beta (Swift 1.2) this is finally fixed, you can do it now like this:

let boundingRect = "string".boundingRectWithSize(size, options: .UsesLineFragmentOrigin | .UsesFontLeading, attributes:nil, context:nil)

For old version:

It looks like a bug in current beta, for now I write Objective-C method and use it from Swift:

+ (NSStringDrawingOptions)combine:(NSStringDrawingOptions)option1 with:(NSStringDrawingOptions)option2
{
    return option1 | option2;
}

and call form Swift:

let boundingRect = "string".boundingRectWithSize(size, options: StringDrawingOptions.combine(.UsesLineFragmentOrigin, with: .UsesFontLeading), attributes:nil, context:nil)