このページは「相互参照」をもつインスタンスを円満に消去するためのサンプルコードです。
//
// ViewController.swift
// MyApp
//
// Created by Shimizu Miki on 2014/07/31.
// Copyright (c) 2014年 Shimizu Miki. All rights reserved.
//
import UIKit
class Leader{
let name = "ジェフ"
var message:String
var tour:Tour?
init(){
message = "こんにちは、\(name)です！\n"
}
func planTour(tourName:String){
self.tour = Tour(name:tourName)
tour!.leader = self
message += "今度、\(tour!.name)に行くよ！\n"
}
func addBass(bassist:Musician){
tour!.addBass(bassist)
message += "\(bassist.name)期待してるぜ!\n"
}
func addDrums(drummer:Musician){
tour!.addDrums(drummer)
message += "\(drummer.name)期待してるぜ!\n"
}
func delBass(){
tour!.delBass()
message += "そいつは残念だ!\n"
}
func delDrums(){
tour!.delDrums()
message += "そいつは残念だ!\n"
}
func cancelTour(){
if (tour != nil){
tour = nil
}
}
func reportMessage()->String{
return message
}
}
class Tour{
let name:String
var leader:Leader?
var bass:Musician?
var drums:Musician?
init(name:String){
self.name = name
}
func addBass(bassist:Musician){
bass = bassist
bass!.tour = self
bass!.leader = self.leader
bass!.joinTour()
}
func addDrums(drummer:Musician){
drums = drummer
drums!.tour = self
drums!.leader = self.leader
drums!.joinTour()
}
func delBass(){
if(bass != nil){
bass!.cancelTour()
bass = nil
}
}
func delDrums(){
if(drums != nil){
drums!.cancelTour()
drums = nil
}
}
deinit{
if (leader != nil){
leader!.message += "バッドニュースだ。\(name)は中止になっちゃったんだ。この次は必ず行くよ！"
}
}
}
class Musician{
let name:String
var part:String
var leader:Leader?
var tour:Tour?
init(name:String, part:String){
self.name = name
self.part = part
}
func joinTour(){
if(leader != nil && tour != nil){
leader!.message += "「\(name)です。\(tour!.name)に参加できて嬉しいです。」\n"
}
}
func cancelTour(){
if (leader != nil && tour != nil){
leader!.message += "「\(name)です。\(tour!.name)にいけなくなって残念です。」\n"
tour = nil
}
}
}
class ViewController: UIViewController {
@IBOutlet weak var resultText: UITextView!
override func viewDidLoad() {
super.viewDidLoad()
var myStr = ""
let jeff = Leader()
jeff.planTour("2014アメリカ横断スーパーツアー")
let tony = Musician(name:"トニー", part:"ベース")
let bill = Musician(name:"ビル", part:"ドラム")
jeff.addBass(tony)
jeff.addDrums(bill)
jeff.delBass()
jeff.delDrums()
jeff.cancelTour()
myStr += jeff.reportMessage()
resultText.text = myStr
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}