Apple Swift Programming: 第 7 個程式：導覽控制器 Navigator 與 Segue


1. 加入 Navigation Controller，以 Seque = Push 來連接 Navigation Controller 與 Table View Controller.

首先，點選 Table View Controller，然後點選 Editor > Embed In > Navigation Controller:



這時 Navigation Controller 被自動設定為 Initial View Controller，且連結 Table View Controller。

2. 加入 View Controller 這 UI，以 Segue = Push 來連接 Table View Controller (Source) 與 View Controller (Destination)

先新增 View Controller，之後在 Table View Controller 選取 Cell，然後按下 Control 鍵不放，拖曳至新的 View Controller 上，此時設定 Segue = Push：



點選後，新的 Segue 連接了 Table View Controller 與 View Controller:



3. 在這新的 View Controller 的 Destination View Controller 上，新增 Lable 以顯示 Table View 被選取後的資料



接著給這新的 Segue 一個 ID:



在這之前，我們整個 UI 算是完成，接下來我們要控制這些 UI 元件。

4. 然後新增此 UI 物件的類別，將此類別 Assign 到此 UI (即這 UI 與這 Class 關聯)

新增 View Controller 類別：



然後新增此 UI 物件的類別，將此類別 Assign 到此 UI (即這 UI 與這 Class 關聯)

然後，將此類別 Assign 到此 UI ：



5. 實作點選 Source Controller 上的 Cell後，在 Destination Controller 能顯示此資料：

點選 Destination Controller 上的 Label，並按 Control 鍵不放，拖曳至 Code 中：



Detail View Controller 的程式修改如下：



接下來處理 Table View 資料選取後，傳遞到 View Controller 再處理，傳遞方式是 Source View Controller 會呼叫 prepareForSegue 這方法：




６. 在 Source View Controller 實作 prepareForSegue，當選取資料時，資料能傳遞到 Destination Controller



測試：

Run 後顯示的 UI:



點選第一行資料 book，測試是否資料會傳遞到下一個 UI 畫面：



程式碼：

Table View Controller:


//
//  MyTableViewController.swift
//  SimpleTableViewControllerDemo
//
//  Created by Elvis Meng on 2015/9/6.
//  Copyright (c) 2015年 Elvis Meng. All rights reserved.
//

import UIKit

class MyTableViewController: UITableViewController, UITableViewDataSource, UITableViewDelegate {
    
    var vocabulary = ["book","pen","queen","1","2","3","4","5","6","7","8","9","10","11","12","13","14","15"]

    override func viewDidLoad() {
        super.viewDidLoad()

        // Uncomment the following line to preserve selection between presentations
        // self.clearsSelectionOnViewWillAppear = false

        // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
        // self.navigationItem.rightBarButtonItem = self.editButtonItem()
        
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    // MARK: - Table view data source

    override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        // #warning Potentially incomplete method implementation.
        // Return the number of sections.
        return 1
    }

    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        // #warning Incomplete method implementation.
        // Return the number of rows in the section.
        return self.vocabulary.count
    }
   
    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        
        let cellIdentifier = "Cell"
        let cell = tableView.dequeueReusableCellWithIdentifier(cellIdentifier, forIndexPath: indexPath) as! UITableViewCell

        // Configure the cell...
        cell.textLabel?.text = vocabulary[indexPath.row]
        
        return cell
    }

    override func tableView(tableView: UITableView,
        didSelectRowAtIndexPath indexPath: NSIndexPath) {
            
            let cell: UITableViewCell = tableView.cellForRowAtIndexPath(indexPath)!
            if cell.accessoryType == UITableViewCellAccessoryType.None {
                cell.accessoryType = UITableViewCellAccessoryType.Checkmark
            } else {
                cell.accessoryType = UITableViewCellAccessoryType.None
            }
            tableView.deselectRowAtIndexPath(indexPath, animated: true)
    }
 

    override func tableView(tableView: UITableView,
        didDeselectRowAtIndexPath indexPath: NSIndexPath) {
            let cell: UITableViewCell = tableView.cellForRowAtIndexPath(indexPath)!
            if cell.accessoryType == UITableViewCellAccessoryType.None {
                cell.accessoryType = UITableViewCellAccessoryType.Checkmark
            } else {
                cell.accessoryType = UITableViewCellAccessoryType.None
            }
            tableView.deselectRowAtIndexPath(indexPath, animated: false)
    }

    
    override func tableView(tableView: UITableView,
        commitEditingStyle editingStyle: UITableViewCellEditingStyle,
        forRowAtIndexPath indexPath: NSIndexPath) {
            
            if editingStyle == .Delete {
                self.vocabulary.removeAtIndex(indexPath.row)
                //tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
                self.tableView.reloadData()
            } else if editingStyle == .Insert {
                self.vocabulary.insert("new", atIndex: indexPath.row)
                self.tableView.reloadData()
            }
    }

    override func tableView(tableView: UITableView, editActionsForRowAtIndexPath indexPath: NSIndexPath) -> [AnyObject]? {
        
        var deleteAction = UITableViewRowAction(style: UITableViewRowActionStyle.Default, title: "Delete",
            handler: {(action:UITableViewRowAction!,
            indexPath: NSIndexPath!) -> Void in
            
                self.vocabulary.removeAtIndex(indexPath.row)
                self.tableView.reloadData()
            
            }

        )
        
        let alertAction = UITableViewRowAction(style : UITableViewRowActionStyle.Default,title : "Share",
            handler : {(action:UITableViewRowAction!,
            indexPath: NSIndexPath!) -> Void in
                let alertController = UIAlertController(title:"My First App",
                    message:"Hello World",
                    preferredStyle: .Alert)
                let alertAction = UIAlertAction(title:"OK",
                    style: UIAlertActionStyle.Default,
                    handler:nil)
                alertController.addAction(alertAction)
                
                self.presentViewController(alertController,
                    animated: true,
                    completion: nil)
            }
        )
        
        return [deleteAction, alertAction]
    }
    
    


  /*
    // Override to support editing the table view.
    override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
        if editingStyle == .Delete {
            // Delete the row from the data source
            tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
        } else if editingStyle == .Insert {
            // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
        }    
    }
*/

    /*
    // Override to support rearranging the table view.
    override func tableView(tableView: UITableView, moveRowAtIndexPath fromIndexPath: NSIndexPath, toIndexPath: NSIndexPath) {

    }
    */

    /*
    // Override to support conditional rearranging of the table view.
    override func tableView(tableView: UITableView, canMoveRowAtIndexPath indexPath: NSIndexPath) -> Bool {
        // Return NO if you do not want the item to be re-orderable.
        return true
    }
    */

    
    // MARK: - Navigation

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

        if segue.identifier == "detailSegue" {
            
            let indexPath = self.tableView.indexPathForSelectedRow()
            var destinationController = segue.destinationViewController as! DetailViewController
            destinationController.senderText = self.vocabulary[indexPath!.row]
            
        }
    }

}



Detail View Controller:


//
//  DetailViewController.swift
//  SimpleTableViewControllerDemo
//
//  Created by Elvis Meng on 2015/9/12.
//  Copyright (c) 2015年 Elvis Meng. All rights reserved.
//

import UIKit

class DetailViewController: UIViewController {

    @IBOutlet var word: UILabel!
    var senderText:String!
    
    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        
        self.word.text = senderText
   
        
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    

    /*
    // MARK: - Navigation

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

}


參考：

1. Segue Compatibility, https://developer.apple.com/library/prerelease/ios/recipes/xcode_help-IB_storyboard/Chapters/BackwardCompatibilityofActiveSegues.html

2. UIViewController，https://developer.apple.com/library/prerelease/tvos/documentation/UIKit/Reference/UIViewController_Class/