gistfile1.swift

import UIKit

class ViewController: UIViewController {

    
    @IBOutlet weak var costLabel: UITextField!
    @IBOutlet weak var taxLabel: UITextField!
    @IBOutlet weak var taxCostLabel: UILabel!
    
    var taxCost:Int = 0
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        
        //税込金額の初期化
        self.taxCostLabel.text = "\(taxCost)"
        
        //消費税率の呼び出し処理
        let defaults = NSUserDefaults.standardUserDefaults()
        
        //保存されていたら呼び出してラベル表示
        if let storeTax = defaults.valueForKey("tax") as? Double{
            
            self.taxLabel.text = "\(Int(storeTax))"
        }
        
        
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    
    @IBAction func pressCalculateButton(sender: AnyObject) {
        //税抜金額
        let cost = (self.costLabel.text as NSString).doubleValue
        
        //消費税率
        let tax = (self.taxLabel.text as NSString).doubleValue
        
        //税込金額計算
        let taxCost = cost * (1 + tax/100)
        
        //税込金額表示
        self.taxCostLabel.text = "\(Int(taxCost))"
        
        //消費税率保存処理
        let defaults = NSUserDefaults.standardUserDefaults()
        defaults.setDouble(tax, forKey: "tax")
        defaults.synchronize()
        
        //キーボードを外す処理
        self.costLabel.resignFirstResponder()
        self.taxLabel.resignFirstResponder()
        
    }


}