swift - Sorting Tableview Rows By Multiple Arrays -


i trying sort tableview words on labels in each row. each row have 3 things: color, animal type, , name animal. have specific order in mind on how want organize table, depending on how items loaded, order of rows can (the problem).

i want sort these tables color array: colorarray = ["red", "blue", "yellow", "green", "orange", "purple"]. mean red animals first while green ones in middle etc. first problem not know how sort array string array. second problem need other 2 arrays (animal , animal name) change order in accordance color array right animal , names' correct color.

example: if color array loaded in blue, green, orange, red , animal array loaded in dog, cow, cat, monkey, need need these 2 array sorted red, blue, green orange , monkey, dog, cow, cat. animals right color. how fix these 2 problems? have copied current code @ bottom:

    func loadanimals() {             let animalquery = pfquery(classname: "animals")             animalquery.wherekey("userid", equalto: pfuser.current()?.objectid! ?? string()) //getting user             animalquery.limit = 10             animalquery.findobjectsinbackground { (objects, error) in                 if error == nil {                     self.colorarray.removeall(keepingcapacity: false)                     self.animalnamearray.removeall(keepingcapacity: false)                                     self.animaltypearray.removeall(keepingcapacity: false)                      object in objects! {                         self.colorarray.append(object.value(forkey: "colortype") as! string) // add data arrays                         self.animalnamearray.append(object.value(forkey: "animalname") as! string) // add data arrays                                             self.animaltypearray.append(object.value(forkey: "animaltype") as! string) // add data arrays                     }                     self.tableview.reloaddata()                  } else {                     print(error?.localizeddescription ?? string())                 }             }         }      //places colors in rows     override func tableview(_ tableview: uitableview, cellforrowat indexpath: indexpath) -> uitableviewcell {             let cell = tableview.dequeuereusablecell(withidentifier: "cell") as! animalcell //connects color cell              //adds animal information in cells             cell.colortype.text = colorarray[indexpath.row]              cell.animalname.text = animalnamearray[indexpath.row]              cell.animaltype.text = animaltypearray[indexpath.row]               return cell         }

never use multiple arrays data source. error-prone , annoying maintain. use custom struct, object oriented language.

  • create struct, color string mapped index , vice versa

    struct animal {      static let colors = ["red", "blue", "yellow", "green", "orange", "purple"]      let name : string     let type : string     let colorindex : int      init(name : string, type : string, color : string) {         self.name = name         self.type = type         self.colorindex = animal.colors.index(of: color)!     }      var color : string  {         return animal.colors[colorindex]     }  }

  • and data source array

    var animals = [animal]()

  • replace loadanimals() with

    func loadanimals() {     let animalquery = pfquery(classname: "animals")     animalquery.wherekey("userid", equalto: pfuser.current()?.objectid! ?? string()) //getting user     animalquery.limit = 10     animalquery.findobjectsinbackground { (objects, error) in         if error == nil {             animals.removeall()              object in objects! {                 animals.append(animal(name: object["animalname") as! string, type: object["animaltype") as! string, color: object["colortype") as! string)             }             self.tableview.reloaddata()          } else {             print(error?.localizeddescription ?? string())         }     } }

  • and cellforrow 

    override func tableview(_ tableview: uitableview, cellforrowat indexpath: indexpath) -> uitableviewcell {     let cell = tableview.dequeuereusablecell(withidentifier: "cell", for: indexpath) as! animalcell //connects color cell      //adds animal information in cells     let animal = animals[indexpath.row]     cell.colortype.text = animal.color     cell.animalname.text = animal.name     cell.animaltype.text = animal.type      return cell }

  • now sort animals colorindex , order want

    animals.sort{ $0.colorindex < $1.colorindex }

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