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swiftswift4nsattributedstring

Cannot convert value of type 'NSAttributedString.DocumentAttributeKey' , "DocumentReadingOptionKey" also not working

I upgraded from Swift 3 to Swift 4 and I get the NSAttributedString related error.

Here's my code:

viewModel.getInviteAFriendInfo(success: { message in
    if message.isEmpty{
        self.lblDetail.text = "xxxxxxx"
    }else{
        let htmlString: String = "<html><head><style xxxxxx </style></head><body>\(message)</body></html>"
        self.lblDetail.setText(try! NSAttributedString(data: htmlString.data(using: .unicode, allowLossyConversion: true)!, options: [NSAttributedString.DocumentAttributeKey.documentType:NSAttributedString.DocumentType.html,NSAttributedStringKey.kern: 2.0], documentAttributes: nil))
    }
}, failure: {
    self.showAlert("Failed to get text")
})

Here's my error:

Cannot convert value of type 'NSAttributedString.DocumentAttributeKey' to expected dictionary key type 'NSAttributedString.DocumentReadingOptionKey'

Read some posted questions and solutions, tried to change NSAttributedString.DocumentAttributedKey into NSAttributedString.DocumentReadingOptionKey, but still got error.

Solution

  • The value you are trying to pass to the options parameter needs to be split up.

    First, the documentType is from NSAttributedString.DocumentReadingOptionKey, not NSAttributedString.DocumentAttributeKey.

    Seconds, the kern needs to be passed to the documentAttributes parameter, not the options parameter.

    It's much easier if you split up the code:

    let options: [NSAttributedString.DocumentReadingOptionKey : Any] = [ .documentType: NSAttributedString.DocumentType.html ]
let attributes = [ NSAttributedString.Key.kern: 2.0 ] as NSDictionary?
let data = htmlString.data(using: .utf8)!
let attrStr = try? NSAttributedString(data: data, options: options, documentAttributes: &attributes)