swift - NSOutlineView, using item: AnyObject -

i'm creating nsoutlineview. when implementing data source, although i'm able create top hierarchy can not implement childhierarchy. reason can't read item: anyobject? prevents me returning right array dictionary.

 //mark: nsoutlineview var outlinetophierarchy = ["collect", "review", "projects", "areas"] var outlinecontents = ["collect":["a","b"], "review":["c","d"],"projects":["e","f"],"areas":["g","h"]]  //get children item func childrenforitem (itempassed : anyobject?) -> array<string>{     var childrenresult = array<string>()     if(itempassed == nil){ //if no item passed return highest level of hirarchy         childrenresult = outlinetophierarchy     }else{            //issue here:         //need find title call correct child          childrenresult = outlinecontents["collect"]!  //faked, should showing top hierarchy item return right data       }     return childrenresult }   //data source func outlineview(outlineview: nsoutlineview, child index: int, ofitem item: anyobject?) -> anyobject{     return childrenforitem(item)[index] }  func outlineview(outlineview: nsoutlineview, isitemexpandable item: anyobject) -> bool{     if(outlineview.parentforitem(item) == nil){         return true     }else{         return false     } }  func outlineview(outlineview: nsoutlineview, numberofchildrenofitem item: anyobject?) -> int{     return childrenforitem(item).count }   func outlineview(outlineview: nsoutlineview, viewfortablecolumn: nstablecolumn?, item: anyobject) -> nsview? {      // groups, return regular text view.     if (outlinetophierarchy.contains(item as! string)) {         let resulttextfield = outlineview.makeviewwithidentifier("headercell", owner: self) as! nstablecellview         resulttextfield.textfield!.stringvalue = item as! string         return resulttextfield     }else{         // cell setup in ib. textfield , imageview outlets setup.         let resulttextfield = outlineview.makeviewwithidentifier("datacell", owner: self) as! nstablecellview         resulttextfield.textfield!.stringvalue = item as! string         return resulttextfield     }  } 

}

i used reference, although it's objective-c implemented

you need cast item correct type outline. you'd want use real data model, toy problem 2 levels in hierarchy, suffices:

func childrenforitem (itempassed : anyobject?) -> array<string>{     if let item = itempassed {         let item = item as! string         return outlinecontents[item]!     } else {         return outlinetophierarchy     } }