05 장

UINavigationController을 이용한 뷰(UIViewController) 전환, 뷰 간 데이터 전달하기(prepareForSegue)

//  ViewController.swift
//  TableDataPassTest
//  XCode 8.3.2

import UIKit

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    var titleData = ["Korea", "China", "Japan", "England"]
    var subTitleData = ["Seoul", "Peking", "Tyokyo", "Rondon" ]

    @IBOutlet weak var myTableView: UITableView!
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        myTableView.dataSource = self
        myTableView.delegate = self
    }

    // Delegate Methods...
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return titleData.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let myCell = myTableView.dequeueReusableCell(withIdentifier: "myCell", for: indexPath)
        myCell.textLabel?.text = titleData[indexPath.row]
        myCell.detailTextLabel?.text = subTitleData[indexPath.row]
        return myCell
    }

    // Segue를 통해 DetailViewController에 데이터 넘기기
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "goDetail" {
            let detailVC = segue.destination as! DetailViewController

            // 테이블뷰에서 선택한 indexPath.row 
            let selectedPath = myTableView.indexPathForSelectedRow
            detailVC.titleData = titleData[(selectedPath?.row)!]
        }
    }
}

//  DetailViewController.swift
//  TableDataPassTest
import UIKit

class DetailViewController: UIViewController {

    @IBOutlet weak var titleLabel: UILabel!
    var titleData: String?

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        titleLabel.text = titleData

        // Navigation title 설정
        title = titleData
    }

    /*
    // MARK: - Navigation

    // In a storyboard-based application, you will often want to do a little preparation before navigation
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        // Get the new view controller using segue.destinationViewController.
        // Pass the selected object to the new view controller.
    }
    */
}

//  ViewController.swift
//  ViewController Switching & Data Passing
import UIKit
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
    @IBOutlet var tableView: UITableView!
    var data = ["Dog", "Cat", "Cow", "Pig", "dolphin"]
    var subData = ["강아지", "고양이", "황소", "돼지", "돌고래"]

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        //4.   delegate 연결
        tableView.delegate = self
        tableView.dataSource = self
    }

    // 1. Delegate 객체에게 Section의 갯수 생성 요청
    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return 1
    }

    // 2. Delegate 객체에게 Section 내의 row의 갯수 생성 요청
    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return data.count
    }

    // 3. cell의 메모리 할당 생성 및 데이터 출력
    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        //let cell = tableView.dequeueReusableCellWithIdentifier("cell") as UITableViewCell!

        let cell:UITableViewCell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
        //let row = indexPath.row

        cell.textLabel?.text = data[indexPath.row]
        cell.detailTextLabel?.text = subData[indexPath.row]

        // cell image 넣기
        let myImage = UIImage(named: data[indexPath.row]+".jpg")
        //let myImageView = UIImageView(image: myImage)
        cell.imageView?.image = myImage

        /// Accessory Type
//        if indexPath.row == 0 {
//            cell.accessoryType = UITableViewCellAccessoryType.Checkmark
//        } else if indexPath.row == 1 {
//            cell.accessoryType = UITableViewCellAccessoryType.DetailButton
//        } else if indexPath.row == 2 {
//            cell.accessoryType = UITableViewCellAccessoryType.DetailDisclosureButton
//        } else {
//            cell.accessoryType = UITableViewCellAccessoryType.DisclosureIndicator
//        }

        return cell 
    }

    // cell 지우기
    func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {

        if editingStyle == UITableViewCellEditingStyle.Delete {
            data.removeAtIndex(indexPath.row)
            tableView.reloadData()
        }
    }

    // ViewController의 데이터를 DetailViewController로 전달하기
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "goDetail" {
            if let detailVC = segue.destinationViewController as? DetailViewController {

                let path = tableView.indexPathForSelectedRow

                // Data를 label에 넘기기
                detailVC.myData = data[(path?.row)!]

                // subData를 네비게이션 바의 title에 넘기기
                detailVC.title = subData[(path?.row)!]

                // 이미지 넘기기
                detailVC.detailImage = data[(path?.row)!] + ".jpg"

            }
        }
    }

    // cell을 tap 할때 index 출력
    // UITableViewDelegate에 있는 메소드
    //    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
    //        print("You selected \(indexPath.section)th section... \(indexPath.row)th row")
    //
    //
    //    }

    // section Header 설정
    // UITableViewDataSource에 있는 메소드
    //    func tableView(tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
    //        return "Section \(section)"
    //    } 
}

//  DetailViewController.swift

import UIKit
class DetailViewController: UIViewController {
    @IBOutlet var detailData: UILabel!
    @IBOutlet var myImageView: UIImageView!

    var myData:String?
    var mySubData:String?
    var detailImage:String?

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        detailData.text = myData
        //title = "title Test"
        myImageView.image = UIImage(named: detailImage!)
    }
}

형변환(downcasting)에 대하여? as!, as?

• as?는 변환하고자 하는 형(downcast type)의 optional 값을 return 함(conditional downcast)
• as!는 force-unwrap 형태로 변환 함. as!는 다운캐스팅이 항상 성공적인 것을 확신할때 사용되며, 그렇지 않을 경우 runtime 오류가 발생함 (forced downcast)

// ViewController의 데이터를 DetailViewController로 전달하기
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "goDetail" {
            if let detailVC = segue.destinationViewController as? DetailViewController {             
                let path = tableView.indexPathForSelectedRow
                // Data를 label에 넘기기
                detailVC.myData = data[(path?.row)!]
                // subData를 네비게이션 바의 title에 넘기기
                detailVC.title = subData[(path?.row)!]
                // 이미지 넘기기
                detailVC.detailImage = data[(path?.row)!] + ".jpg"       
            }
        }
    }

UIWebView 사용하기

• iOS 앱에서 웹(HTTP) 페이지를 접근하기 위한 보안 설정 방법(info.plist 화일 편집)

//  ViewController.swift
//  WebView Test

import UIKit
class ViewController: UIViewController, UIWebViewDelegate {
    @IBOutlet var myWebView: UIWebView!
    @IBOutlet var myActivityIndicator: UIActivityIndicatorView!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        // Webview delegate 연결
        myWebView.delegate = self

        // 1. resource를 표햔하는 URL 객체 생성
        //let myURL = NSURL(string: "http://www.apple.com")
        let myURL = NSURL(string: "http://m.google.com")

        // 2. URL request 객체 생성
        let myURLRequest = NSURLRequest(URL: myURL!)

        // 3. load request
        myWebView.loadRequest(myURLRequest)  
    }

    // UIVebview Delegate functions
    // Activity Indicator animation start
    func webViewDidStartLoad(webView: UIWebView) {
        myActivityIndicator.startAnimating()
    }

    // Activity Indicator animation stop
    func webViewDidFinishLoad(webView: UIWebView) {
        myActivityIndicator.stopAnimating() 
    }

    // 웹전송 오류 발생
    func webView(webView: UIWebView, didFailLoadWithError error: NSError?) {
        print("network error 발생")
    }
}

UITabBarController 사용하기

• Starter file download

//  ViewController.swift
//  ViewController Switching & Data Passing

import UIKit
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
    @IBOutlet var tableView: UITableView!
    var data = ["Dog", "Cat", "Cow", "Pig", "dolphin"]
    var subData = ["강아지", "고양이", "황소", "돼지", "돌고래"]

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        //4.   delegate 연결
        tableView.delegate = self
        tableView.dataSource = self
    }

    // 1. Delegate 객체에게 Section의 갯수 생성 요청
    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return 1
    }

    // 2. Delegate 객체에게 Section 내의 row의 갯수 생성 요청
    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return data.count
    }

    // 3. cell의 메모리 할당 생성 및 데이터 출력
    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        //let cell = tableView.dequeueReusableCellWithIdentifier("cell") as UITableViewCell!

        let cell:UITableViewCell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath)
        //let row = indexPath.row

        cell.textLabel?.text = data[indexPath.row]
        cell.detailTextLabel?.text = subData[indexPath.row]

        // cell image 넣기
        let myImage = UIImage(named: data[indexPath.row]+".jpg")
        //let myImageView = UIImageView(image: myImage)
        cell.imageView?.image = myImage

        return cell  
    }

    // cell 지우기
    func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
        if editingStyle == UITableViewCellEditingStyle.Delete {
            data.removeAtIndex(indexPath.row)
            tableView.reloadData()
        }
    }

    // ViewController의 데이터를 DetailViewController로 전달하기
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "goDetail" {

            if let detailVC = segue.destinationViewController as? DetailViewController {

                let path = tableView.indexPathForSelectedRow

                // Data를 label에 넘기기
                detailVC.myData = data[(path?.row)!]

                // subData를 네비게이션 바의 title에 넘기기
                detailVC.title = subData[(path?.row)!]

                // 이미지 넘기기
                detailVC.detailImage = data[(path?.row)!] + ".jpg"

            }
        }
    }
}

//  DetailViewController.swift

import UIKit

class DetailViewController: UIViewController {

    @IBOutlet var detailData: UILabel!
    @IBOutlet var myImageView: UIImageView!

    var myData:String?
    var mySubData:String?
    var detailImage:String?

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        detailData.text = myData
        //title = "title Test"
        myImageView.image = UIImage(named: detailImage!)
    }
}

//  WebViewController.swift
import UIKit
class WebViewController: UIViewController {

    @IBOutlet var myWebView: UIWebView!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        if let url = NSURL(string: "https://www.instagram.com/explore/tags/animal/") {
            let request = NSURLRequest(URL: url)
            myWebView.loadRequest(request)
        }

            // forced unwrapping
            /*
            let url = NSURL(string: "https://www.instagram.com/explore/tags/animal/")
            let request = NSURLRequest(URL: url!)
            myWebView.loadRequest(request)
            */
    }
}

[코딩 문제 12] Segue를 이용하여 ViewController 간의 데이터 넘겨 주기

• Button을 터치하면 두개의 ViewController 간 Button(I love iOS, Happy Coding)에 있는 title 스트링 값을 전달하여 Lable(I love iOS, Happy Coding)에 출력한다.

FirstViewController

SecondViewController

FirstViewController