ios开发中使用coreData来数据存储及获取

  1 //
  2 //  TableViewController.swift
  3 //  练习tableview
  4 //
  5 //  Created by xiaos on 15-3-15.
  6 //  Copyright (c) 2015年 xiaos. All rights reserved.
  7 //
  8 
  9 import UIKit
 10 import CoreData
 11 
 12 class TableViewController: UITableViewController {
 13     
 14     //添加姓名按钮
 15     @IBAction func addName(sender: AnyObject) {
　　　　　　　　//以警告框的形式
 16         var alert = UIAlertController(title: "添加", message:"添加一个名字", preferredStyle: UIAlertControllerStyle.Alert)
 17         //保存按钮
 18         let saveAction = UIAlertAction(title: "保存", style: UIAlertActionStyle.Default,handler: {(action:UIAlertAction!) -> Void in
 19             
 20             let textField = alert.textFields![0] as UITextField
　　　　　　　　　　//调用下面的saveName方法
 21             self.saveName(textField.text)
 22 //            self.tableView.reloadData()

　　　　　　　　　//定义一个路径来确定插入单元格的位置 和 设置插入动画
 23             let indexPath = NSIndexPath(forRow: (self.people.count-1), inSection: 0)
 24             self.tableView.insertRowsAtIndexPaths([indexPath], withRowAnimation: UITableViewRowAnimation.Left)
 25             
 26         })
 27         //取消按钮
 28         let cannelAction = UIAlertAction(title: "取消", style: UIAlertActionStyle.Default,handler: nil)
 29         //在alert中添加按钮
 30         alert.addAction(saveAction)
 31         alert.addAction(cannelAction)
 32         //在alert中添加文本框
 33         alert.addTextFieldWithConfigurationHandler { (textField:UITextField!) -> Void in}
 34         
 35         
 36         //在视图中弹出alert
 37         self.presentViewController(alert, animated: true, completion: nil)
 38             
 39             
 40         
 41         
 42             
 43             
 44     }
 45     
 46     //保存数据，分5个步骤
 47     func saveName(name:String){
 48         
 49         //1、取得总代理和托管对象内容总管
 50         let appDelegate = UIApplication.sharedApplication().delegate as AppDelegate
 51         
 52         let managedContext = appDelegate.managedObjectContext!
 53         
 54         //2、建立一个entity
 55         let entity = NSEntityDescription.entityForName("Person", inManagedObjectContext: managedContext)
 56         
 57         let person = NSManagedObject(entity: entity!, insertIntoManagedObjectContext: managedContext)
 58         
 59         //3、保存文本框中的值到person
 60         person.setValue(name, forKey: "name")
 61         
 62         //4、保存entity到托管对象总管中
 63         var error:NSError?
 64         if !managedContext.save(&error){
 65             println("Could not save \(error),\(error?.userInfo)")
 66         }
 67         //5、保存到数组中，更新ui
 68         people.append(person)
 69     }
 70     
 71     //姓名字典
 72      73     
 74     //core data对象
 75     var people = [NSManagedObject]()
 76     
 77     
 78     override func viewDidLoad() {
 79         super.viewDidLoad()
 80         
 81 //        title = "列表"
 82         // Uncomment the following line to preserve selection between presentations
 83         // self.clearsSelectionOnViewWillAppear = false
 84 
 85         // Uncomment the following line to display an Edit button in the navigation bar for this view controller.
 86         // self.navigationItem.rightBarButtonItem = self.editButtonItem()
 87     }
 88     
 89     //获取数据  分3步
 90     override func viewDidAppear(animated: Bool) {
 91         //1、取得总代理和托管对象内容总管
 92         let appDelegate = UIApplication.sharedApplication().delegate as AppDelegate
 93         
 94         let managedContext = appDelegate.managedObjectContext!
 95         //2、建立一个获取的请求
 96         let fetchRequest = NSFetchRequest(entityName: "Person")
 97         
 98         //3、执行请求
 99         var error:NSError?
100         
101         let fetchedResults = managedContext.executeFetchRequest(fetchRequest, error: &error) as [NSManagedObject]?
102         
103         if let results = fetchedResults{
104             people = results
105             self.tableView.reloadData()
106         }else{
107             println("Could not save \(error),\(error?.userInfo)")
108         }
109         
110     }
111     
112     override func didReceiveMemoryWarning() {
113         super.didReceiveMemoryWarning()
114         // Dispose of any resources that can be recreated.
115     }
116 
117     // MARK: - Table view data source
118     
119     //表格部分
120     override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
121         // #warning Potentially incomplete method implementation.
122         // Return the number of sections.
123         return 1
124     }
125     
126     //表格行数
127     override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
128         // #warning Incomplete method implementation.
129         // Return the number of rows in the section.
130         return people.count
131     }
132 
133     //cell的内容
134     override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
135         let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as UITableViewCell
136 
137         cell.textLabel?.text = people[indexPath.row].valueForKey("name") as String?
138         
139         
140         return cell
141     }
142     
143 
144     /*
145     // Override to support conditional editing of the table view.
146     override func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -> Bool {
147         // Return NO if you do not want the specified item to be editable.
148         return true
149     }
150     */
151 
152     /*
153     // Override to support editing the table view.
154     override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
155         if editingStyle == .Delete {
156             // Delete the row from the data source
157             tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
158         } else if editingStyle == .Insert {
159             // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
160         }    
161     }
162     */
163 
164     /*
165     // Override to support rearranging the table view.
166     override func tableView(tableView: UITableView, moveRowAtIndexPath fromIndexPath: NSIndexPath, toIndexPath: NSIndexPath) {
167 
168     }
169     */
170 
171     /*
172     // Override to support conditional rearranging of the table view.
173     override func tableView(tableView: UITableView, canMoveRowAtIndexPath indexPath: NSIndexPath) -> Bool {
174         // Return NO if you do not want the item to be re-orderable.
175         return true
176     }
177     */
178 
179     /*
180     // MARK: - Navigation
181 
182     // In a storyboard-based application, you will often want to do a little preparation before navigation
183     override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
184         // Get the new view controller using [segue destinationViewController].
185         // Pass the selected object to the new view controller.
186     }
187     */
188 
189 }