How to update key of dictionary in Swift 3 - 


if (userfollowingarray[indexpath.row]["watcher_following"] as! bool) == false {     let dict : nsmutabledictionary = userfollowingarray[indexpath.row] as! nsmutabledictionary     print(dict)     dict["watcher_following"] = 1     self.userfollowingarray[indexpath.row] = dict as! dictionary<string, any> }

i want update watcher_following key true/false throws exception.

[_ttgcs26_swiftdeferrednsdictionaryssp__ _swift_setobject:forkeyedsubscript:]: unrecognized selector sent instance

do not use nsmutable... collection types in swift

  • declare userfollowingarray swift array

    var userfollowingarray = [[string:any]]()

  • get dictionary variable

    var dict = userfollowingarray[indexpath.row]

  • check value

    if dict["watcher_following"] as! bool == false {

  • update if necessary , assign dictionary array. 

        dict["watcher_following"] = true     userfollowingarray[indexpath.row] = dict }

    the last step necessary due value semantics

it's more convenient use custom struct or class rather dicionary.


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