Swift CFDictionaryCreateMutable

Question

I'm trying to create a PDF document in iOS using Quartz 2D. When I try to define a dictionary to set PDF metadata a get this error:

Cannot invoke 'CFDictionaryCreateMutable' with an argument list of type '(CFAllocator!, Int, CFDictionaryKeyCallBacks, CFDictionaryValueCallBacks)'

Here is how I defined my dictionary:

var documentInfo = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, kCFTypeDictionaryKeyCallBacks, kCFTypeDictionaryValueCallBacks)

Answer 1

First, create swift dictionary.

var wDict = [ "KEY": "VALUE" ]

And cast it to CFDictionaryRef when needed to create PDF.

var documentInfo = wDict as CFDictionaryRef