swift3.0 coreData的使用-日记本demo效果需求分析创建工程添加数据库改写Detail页面改写Master页面Demo地址

- 主要功能：增、删、改、查
- 界面用默认的界面，将detail页面改为`UITextView`可编辑
- 主页面进行 增、删、查操作
- 子页面进行 删、改、查操作

    //当前entity
    var detailItem: Event? {
        didSet {
            // Update the view.
            self.configureView()
        }
    }

//删除
    @IBAction func deleteNote(_ sender: Any) {
        print("deleted")
        let context = self.detailItem?.managedObjectContext
        context?.delete(self.detailItem!)
          //保存到数据库
        self.saveData(context: context!)
        _ = self.navigationController?.popViewController(animated: true)

    }

//保存数据
    func saveObject() {
        print("saved")
        let newEvent = self.detailItem
        let context = self.detailItem?.managedObjectContext
        newEvent?.noteDetail = self.detailTextView.text
        newEvent?.timestamp = NSDate()
        //保存到数据库
        self.saveData(context: context!)
        //返回
        _ = self.navigationController?.popViewController(animated: true)
    }

    //保存数据
    func saveData(context:NSManagedObjectContext) {
        do {
            try context.save()
        } catch {
            let nserror = error as NSError
            fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
        }
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        //增加保存按钮
        let saveBtn = UIBarButtonItem(barButtonSystemItem: .save, target: self, action: #selector(saveObject))
        self.navigationItem.rightBarButtonItem = saveBtn
        self.title = "写点什么吧..."   
        self.configureView()
    }

    //配置界面 显示日志内容
    func configureView() {
        if let detail = self.detailItem {
            if let textView = self.detailTextView {
                textView.text = detail.noteDetail!.description
            }
        }
    }

- 更改cell展示内容
- 点击cell的页面
- 更改新增日志按钮的方法
- 新增刷新tableview

    //配置cell内容
    func configureCell(_ cell: UITableViewCell, withEvent event: Event) {
        cell.textLabel!.text = event.noteDetail?.description
        cell.detailTextLabel!.text = event.timestamp!.description
    }

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        //点击cell push
        let object = self.fetchedResultsController.object(at: indexPath)
        let story = UIStoryboard(name: "Main", bundle: Bundle.main)
        let controller = story.instantiateViewController(withIdentifier: "detail") as! DetailViewController
        controller.detailItem = object
        self.navigationController?.pushViewController(controller, animated: true)
    }

    //插入新记事本
    func insertNewObject(_ sender: Any) {
        //初始化 插入时间戳 和 空数据
        let context = self.fetchedResultsController.managedObjectContext
        let newEvent = Event(context: context)
        newEvent.timestamp = NSDate()
        newEvent.noteDetail = ""
        //保存
        do {
            try context.save()
        } catch {
            let nserror = error as NSError
            fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
        }
   
        //push
        let story = UIStoryboard(name: "Main", bundle: Bundle.main)
        let controller = story.instantiateViewController(withIdentifier: "detail") as! DetailViewController
        controller.detailItem = newEvent
        self.navigationController?.pushViewController(controller, animated: true)
    }

override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        //返回时刷新数据
        self.tableView.reloadData()
    }