第 6 個程式：Cell 上多重功能的製作: UITableViewRowAction

在 Cell 上我們可客製化 Cell，讓它除了 Delete 這功能外，還有其他功能可選。如何做? 我們要把新的功能 Action 加入 UITableViewRowAction 中。這函數 tableView(_:editActionsForRowAtIndexPath:) (New in tvos 9.0) 被定義在 UITableViewDelegate 這協定中:



也就是說我們要實作此協定:


override func tableView(_ tableView: UITableView,
editActionsForRowAtIndexPath indexPath: NSIndexPath) -> [UITableViewRowAction]? {
}

但，在此協定中我們又該如何把新的 Action 加入? 



我們依文件說明，來加入 Action:


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]
    }


呼! 寫到此，驗證結果:

1. 選取 Cell，然後向左滑，顯示 Share 與 Delete Button 



2. 按下 Share 按鈕



3. 在 Cell 顯示 8 的行，按下 Delete 按鈕



程式碼：

//
//  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.
    }
    */

}



參考：

1.UITableViewRowAction, https://developer.apple.com/library/prerelease/tvos/documentation/UIKit/Reference/UITableViewRowAction_class/