Swift sort array of objects based on boolean value

Question

I\'m looking for a way to sort a Swift array based on a Boolean value.

I\'ve got it working using a cast to NSArray:

var boolSort = NSSortDescriptor(         


        

Answer 1

Swift's arrays can be sorted in place with sort or to a new array with sorted. The single parameter of either function is a closure taking two elements and returning true if the first is ordered before the second. The shortest way to use the closure's parameters is by referring to them as $0 and $1.

For example (to sort the true booleans first):

// In-place:
array.sort { $0.selected && !$1.selected }

// To a new array:
array.sorted { $0.selected && !$1.selected }

(edit: Updated for Swift 3, 4 and 5, previously sort was sortInPlace and sorted was sort.)

Answer 2

New (for Swift 1.2)

return results.sort { $0.selected && !$1.selected }

Old (for Swift 1.0)

Assuming results is of type [VDLProfile] and VDLProfile has a Bool member selected:

return results.sorted { $0.selected < $1.selected }

See documentation for sorted

Answer 3

Swift’s standard library provides a function called sorted, which sorts an array of values of a known type, based on the output of a sorting closure that you provide

reversed = sorted(array) { $0 > $1 }

reversed will be a new array which will be sorted according to the condition given in the closure.