swift - How to program a NSOutlineView? -

i having trouble creating nsoutlineview in xcode 8 (swift 3). have plist file information present in outlineview. plist file looks following (example):

root                      dictionary    *(1 item)     harry watson          dictionary    *(5 items)*         name              string        harry watson         age               int           99         birthplace        string        westminster         birthdate         date          01/01/1000         hobbies           array         *(2 items)*             item 0        string        tennis             item 1        string        piano 

the outlineview should pretty similar, follow:

name            harry watson age             99 birthplace      westminster birthdate       01/01/1000 > hobbies       ...             (<- should expandable) 

i searched nsoutlineview tutorials on google, found raywenderlich.com, read bit in opinion isn't easy. wondering whether me exact example above , give me code examples, regarding function:

func outlineview(_ outlineview: nsoutlineview, viewfor tablecolumn: nstablecolumn?, item: any) -> nsview? {} 

. not sure write in there.

if have questions, let me know.

thanks in advance , kind regards

i find ray wenderlitch's tutorials vary wildly in quality. in-jokes, verbosity, step-by-step handholding assumes know nothing swift nauseating me. here's skinny tutorial cover basics of outline view.

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the key understand nsoutlineview must give each row unique identifier, string or object represent row. nsoutlineview calls item. based on item, query data model fill outline view data.

interface builder setup

we use simple nsoutlineview 2 columns: key , value.

select first column , change identifier keycolumn. select second column , change identifier valuecolumn:

set identifier cell outlineviewcell. need once.

code

copy , paste following viewcontroller.swift:

// data model struct person {     var name: string     var age: int     var birthplace: string     var birthdate: date     var hobbies: [string] }  class viewcontroller: nsviewcontroller {     @iboutlet weak var outlineview: nsoutlineview!      // assume know how load plist skip     // code , use constant simplicity     let person = person(name: "harry watson", age: 99, birthplace: "westminster",                         birthdate: datecomponents(calendar: .current, year: 1985, month: 1, day: 1).date!,                         hobbies: ["tennis", "piano"])      let keys = ["name", "age", "birthplace", "birthdate", "hobbies"]      override func viewdidload() {         super.viewdidload()         outlineview.datasource = self         outlineview.delegate = self     } }  extension viewcontroller: nsoutlineviewdatasource, nsoutlineviewdelegate {      // must give each row unique identifier, referred `item` outline view     //   * top-level rows, use values in `keys` array     //   * hobbies sub-rows, label them ("hobbies", 0), ("hobbies", 1), ...     //     integer index in hobbies array     //     // item == nil means it's "root" row of outline view, not visible     func outlineview(_ outlineview: nsoutlineview, child index: int, ofitem item: any?) -> {         if item == nil {             return keys[index]         } else if let item = item as? string, item == "hobbies" {             return ("hobbies", index)         } else {             return 0         }     }      // tell how many children each row has:     //    * root row has 5 children: name, age, birthplace, birthdate, hobbies     //    * hobbies row has how ever many hobbies there     //    * other rows have no children     func outlineview(_ outlineview: nsoutlineview, numberofchildrenofitem item: any?) -> int {         if item == nil {             return keys.count         } else if let item = item as? string, item == "hobbies" {             return person.hobbies.count         } else {             return 0         }     }      // tell whether row expandable. expandable row hobbies row     func outlineview(_ outlineview: nsoutlineview, isitemexpandable item: any) -> bool {         if let item = item as? string, item == "hobbies" {             return true         } else {             return false         }     }      // set text each row     func outlineview(_ outlineview: nsoutlineview, viewfor tablecolumn: nstablecolumn?, item: any) -> nsview? {         guard let columnidentifier = tablecolumn?.identifier else {             return nil         }          var text = ""          // recall `item` row identiffier         switch (columnidentifier, item) {         case ("keycolumn", let item string):             switch item {             case "name":                 text = "name"             case "age":                 text = "age"             case "birthplace":                 text = "birth place"             case "birthdate":                 text = "birth date"             case "hobbies":                 text = "hobbies"             default:                 break             }         case ("keycolumn", _):             // remember identified hobby sub-rows differently             if let (key, index) = item as? (string, int), key == "hobbies" {                 text = person.hobbies[index]             }         case ("valuecolumn", let item string):             switch item {             case "name":                 text = person.name             case "age":                 text = "\(person.age)"             case "birthplace":                 text = person.birthplace             case "birthdate":                 text = "\(person.birthdate)"             default:                 break             }         default:             text = ""         }          let cell = outlineview.make(withidentifier: "outlineviewcell", owner: self) as! nstablecellview         cell.textfield!.stringvalue = text          return cell     } } 

result

you can use dateformatter nicer date output that's not essential question.