class Connection {
    // MARK:  - NSURLConnectionDataDelegate
    func connectionDidFinishLoading(_: NSURLConnection!) {

    }
}

class Connection {
    // MARK:  - NSURLConnectionDataDelegate
    func connectionDidFinishLoading(_: NSURLConnection!) {
    // TODO: process connection
    }
}

class Connection {
    // MARK:  - NSURLConnectionDataDelegate
    func connectionDidFinishLoading(_: NSURLConnection!) {
        // FIXME: do something
        doSomething()
    }
}

thumbnailImageView.layer.cornerRadius = thumbnailImageView.frame.size.width / 2
thumbnailImageView.clipsToBounds = true

// Create an option menu as an action sheet
let optionMenu = UIAlertController(title: nil, message: "What do you want to do?",preferredStyle: .ActionSheet)
// Add actions to the menu
let cancelAction = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil)
optionMenu.addAction(cancelAction)
// Display the menu
self.presentViewController(optionMenu, animated: true, completion: nil)

let callActionHandler = { (action:UIAlertAction!) -> Void in
    let alertMessage = UIAlertController(title: "Service Unavailable", message: "Sorry,the call feature is not available yet. Please retry later.", preferredStyle: .Alert)
    alertMessage.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
    self.presentViewController(alertMessage, animated: true, completion: nil)
}
let callAction = UIAlertAction(title: "Call " + "123-000-\(indexPath.row)", style: UIAlertActionStyle.Default, handler: callActionHandler)
optionMenu.addAction(callAction)

let isVisitedAction = UIAlertAction(title: "I've been here", style: .Default, handler: {
    (action:UIAlertAction!) -> Void in
    let cell = tableView.cellForRowAtIndexPath(indexPath)
    cell?.accessoryType = .Checkmark
})
optionMenu.addAction(isVisitedAction)

var restaurantIsVisited = [Bool](count: 21, repeatedValue: false)

override func prefersStatusBarHidden() -> Bool {
return true
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
// Return the number of rows in the section.
}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

}

override func tableView(tableView: UITableView!, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath!) {

}

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// Return the number of sections.
return 1
}

override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
    if editingStyle == .Delete {

        // Delete the row from the data source

        // self.restaurantNames.removeAtIndex(indexPath.row)
        // self.restaurantLocations.removeAtIndex(indexPath.row)
        // self.restaurantTypes.removeAtIndex(indexPath.row)
        // self.restaurantIsVisited.removeAtIndex(indexPath.row)
        // self.restaurantImages.removeAtIndex(indexPath.row)

        //self.tableView.reloadData() 更新tableView，推荐使用后者的代码，具有动画效果

        self.tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)

    }
}

override func tableView(tableView: UITableView, editActionsForRowAtIndexPath indexPath: NSIndexPath) -> [AnyObject] {

        var shareAction = UITableViewRowAction(style: UITableViewRowActionStyle.Default, title:"Share", handler: { (action:UITableViewRowAction!, indexPath:NSIndexPath!) -> Void in

        let shareMenu = UIAlertController(title: nil, message: "Share using",preferredStyle: .ActionSheet)

        let twitterAction = UIAlertAction(title: "Twitter", style:UIAlertActionStyle.Default, handler: nil)

        let facebookAction = UIAlertAction(title: "Facebook", style:UIAlertActionStyle.Default, handler: nil)

        let emailAction = UIAlertAction(title: "Email", style: UIAlertActionStyle.Default,handler: nil)

        let cancelAction = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel,handler: nil)

        shareMenu.addAction(twitterAction)
        shareMenu.addAction(facebookAction)
        shareMenu.addAction(emailAction)
        shareMenu.addAction(cancelAction)

        self.presentViewController(shareMenu, animated: true, completion: nil)
    })

    var deleteAction = UITableViewRowAction(style: UITableViewRowActionStyle.Default,title: "Delete",handler: { (action:UITableViewRowAction!, indexPath:NSIndexPath!) -> Void in

        // Delete the row from the data source
        self.restaurantNames.removeAtIndex(indexPath.row)
        self.restaurantLocations.removeAtIndex(indexPath.row)
        self.restaurantTypes.removeAtIndex(indexPath.row)
        self.restaurantIsVisited.removeAtIndex(indexPath.row)
        self.restaurantImages.removeAtIndex(indexPath.row)
        self.tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)

    })

    shareAction.backgroundColor = UIColor(red: 255.0/255.0, green: 166.0/255.0, blue:51.0/255.0, alpha: 1.0)

    deleteAction.backgroundColor = UIColor(red: 51.0/255.0, green: 51.0/255.0, blue:51.0/255.0, alpha: 1.0)

    return [deleteAction, shareAction]
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
    if segue.identifier == "showRestaurantDetail" {
        if let indexPath = self.tableView.indexPathForSelectedRow() {
            let destinationController = segue.destinationViewController as DetailViewController
            destinationController.restaurantImage = self.restaurantImages[indexPath.row]
        }
    }
}

self.tableView.backgroundColor = UIColor(red: 240.0/255.0, green: 240.0/255.0, blue: 240.0/255.0, alpha: 0.2)

cell.backgroundColor = UIColor.clearColor()

self.tableView.tableFooterView = UIView(frame: CGRectZero)

self.tableView.separatorColor = UIColor(red: 240.0/255.0, green: 240.0/255.0, blue: 240.0/255.0,alpha: 0.8)

UINavigationBar.appearance().barTintColor = UIColor(red: 231.0/255.0, green: 95.0/255.0, blue: 53.0/255.0, alpha: 0.3)

UINavigationBar.appearance().titleTextAttributes = [NSForegroundColorAttributeName:UIColor.whiteColor(),NSFontAttributeName: UIFont(name: "AvenirNextCondensed-DemiBold",size: 22.0)]

UINavigationBar.appearance().tintColor = UIColor.whiteColor()

override func viewDidLoad() {
    super.viewDidLoad()
    // Empty back button title
    self.navigationItem.backBarButtonItem = UIBarButtonItem(title: "", style: .Plain, target: nil, action: nil)
}

// 设置导航栏背景色
UINavigationBar.appearance().barTintColor = UIColor(red: 231.0/255.0, green: 95.0/255.0, blue: 53.0/255.0, alpha: 0.3)

// 设置导航栏按钮文字颜色
UINavigationBar.appearance().tintColor = UIColor.whiteColor()

// 设置导航栏标题字体大小及颜色
UINavigationBar.appearance().titleTextAttributes =
[NSForegroundColorAttributeName:UIColor.whiteColor(), NSFontAttributeName:UIFont(name:
"AvenirNextCondensed-DemiBold", size: 22.0)]

title = self.restaurant.name

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)
    // 设置隐藏导航栏
    self.navigationController?.hidesBarsOnSwipe = true
}

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)
    // 设置不隐藏导航栏
    self.navigationController?.hidesBarsOnSwipe = false
    self.navigationController?.setNavigationBarHidden(false, animated: true)
}

override func preferredStatusBarStyle() -> UIStatusBarStyle {
    return .LightContent
}

UIApplication.sharedApplication().statusBarStyle = .LightContent

tableView.estimatedRowHeight = 36.0;//与tableView的rowHeight相等
tableView.rowHeight = UITableViewAutomaticDimension;

@IBAction func close(segue:UIStoryboardSegue) {
}

@IBOutlet weak var backgroundImageView:UIImageView!

var blurEffect = UIBlurEffect(style: UIBlurEffectStyle.Dark)//模糊的样式
var blurEffectView = UIVisualEffectView(effect: blurEffect)//创建UIVisualEffectView
blurEffectView.frame = view.bounds//获取当前ViewController的view.bounds
backgroundImageView.addSubview(blurEffectView)//为backgroundImageView添加蒙板

layer.cornerRadius Number 30

// 设置UIBarButtonItem的颜色
UIBarButtonItem.appearance().tintColor = UIColor(red: 235.0/255.0, green: 73.0/255.0, blue: 27.0/255.0, alpha: 1.0)
// 设置UIToolbar的背景色
UIToolbar.appearance().barTintColor = UIColor(red: 237.0/255.0, green: 240.0/255.0, blue: 243.0/255.0, alpha: 0.5)

dialogView.transform = CGAffineTransformMakeScale(0.0, 0.0)

override func viewDidAppear(animated: Bool) {
    UIView.animateWithDuration(0.7, delay: 0.0, options: nil, animations: {
        self.dialogView.transform = CGAffineTransformMakeScale(1, 1)
    }, completion: nil)
}

UIView.animateWithDuration(0.7, delay: 0.0, usingSpringWithDamping: 0.5, initialSpringVelocity: 0.5, options: nil, animations: {
    self.dialogView.transform = CGAffineTransformMakeScale(1, 1)
}, completion: nil)

dialogView.transform = CGAffineTransformMakeTranslation(0, 500)

override func viewDidAppear(animated: Bool) {
    // Spring animation
    UIView.animateWithDuration(0.7, delay: 0.0, usingSpringWithDamping: 0.6, initialSpringVelocity: 0.5, options: nil, animations: {
        self.dialogView.transform = CGAffineTransformMakeTranslation(0, 0)
    }, completion: nil)
}

CGAffineTransformConcat(transform1, transform2)

let scale = CGAffineTransformMakeScale(0.0, 0.0)
let translate = CGAffineTransformMakeTranslation(0, 500)
dialogView.transform = CGAffineTransformConcat(scale, translate)

UIView.animateWithDuration(0.7, delay: 0.0, usingSpringWithDamping: 0.6, initialSpringVelocity: 0.5, options: nil, animations: {
    let scale = CGAffineTransformMakeScale(1, 1)
    let translate = CGAffineTransformMakeTranslation(0, 0)
    self.dialogView.transform = CGAffineTransformConcat(scale, translate)
}, completion: nil)

override func viewDidLoad() {
    super.viewDidLoad()
    // Convert address to coordinate and annotate it on map
    let geoCoder = CLGeocoder()
    geoCoder.geocodeAddressString(restaurant.location, completionHandler: { placemarks,
        error in
        if error != nil {
            println(error)
            return
        }
        if placemarks != nil && placemarks.count > 0 {
            let placemark = placemarks[0] as CLPlacemark
            // Add Annotation
            let annotation = MKPointAnnotation()
            annotation.title = self.restaurant.name
            annotation.subtitle = self.restaurant.type
            annotation.coordinate = placemark.location.coordinate
            self.mapView.showAnnotations([annotation], animated: true)
            self.mapView.selectAnnotation(annotation, animated: true)
        }
    })
}

func mapView(mapView: MKMapView!, viewForAnnotation annotation: MKAnnotation!) -> MKAnnotationView! {
    let identifier = "MyPin"
    if annotation.isKindOfClass(MKUserLocation) {
        return nil
    }

    // Reuse the annotation if possible
    var annotationView = mapView.dequeueReusableAnnotationViewWithIdentifier(identifier)
    if annotationView == nil {
        annotationView = MKAnnotationView(annotation: annotation, reuseIdentifier: identifier)
        annotationView.canShowCallout = true
    }
    let leftIconView = UIImageView(frame: CGRectMake(0, 0, 47, 47))
    leftIconView.image = UIImage(named: restaurant.image)
    annotationView.leftCalloutAccessoryView = leftIconView
    return annotationView
}

if UIImagePickerController.isSourceTypeAvailable(.PhotoLibrary) {
    let imagePicker = UIImagePickerController()
    imagePicker.allowsEditing = false
    imagePicker.sourceType = .PhotoLibrary
    self.presentViewController(imagePicker, animated: true, completion: nil)
}

@IBOutlet weak var imageView:UIImageView!

func imagePickerController(picker: UIImagePickerController!, didFinishPickingImage image: UIImage!, editingInfo: [NSObject : AnyObject]!) {
    imageView.image = image
    imageView.contentMode = UIViewContentMode.ScaleAspectFill
    imageView.clipsToBounds = true
    dismissViewControllerAnimated(true, completion: nil)//dismiss image picker
}

func navigationController(navigationController: UINavigationController!, willShowViewController viewController: UIViewController!, animated: Bool) {
    UIApplication.sharedApplication().setStatusBarStyle(.LightContent, animated: false)
}

name        String
type        String
location    String
image       Binary Data
isVisited   Boolean

import Foundation
import CoreData

class Restaurant:NSManagedObject {
    @NSManaged var name:String!
    @NSManaged var type:String!
    @NSManaged var location:String!
    @NSManaged var image:NSData!
    @NSManaged var isVisited:NSNumber!
}

let managedObjectContext = (UIApplication.sharedApplication().delegate as AppDelegate).managedObjectContext

NSEntityDescription.insertNewObjectForEntityForName("Restaurant", inManagedObjectContext: managedObjectContext) as Restaurant

managedObjectContext.save(&e)

import CoreData

if let managedObjectContext = (UIApplication.sharedApplication().delegate as AppDelegate).managedObjectContext {

    restaurant = NSEntityDescription.insertNewObjectForEntityForName("Restaurant", inManagedObjectContext: managedObjectContext) as Restaurant

    restaurant.name = nameTextField.text
    restaurant.type = typeTextField.text
    restaurant.location = locationTextField.text
    restaurant.image = UIImagePNGRepresentation(imageView.image)
    restaurant.isVisited = isVisited.boolValue//此处与书中有出入

    var e: NSError?

    if managedObjectContext.save(&e) != true {
        println("insert error: \(e!.localizedDescription)")
        return
    }
}

if let managedObjectContext = (UIApplication.sharedApplication().delegate as AppDelegate).managedObjectContext {
    let fetchRequest = NSFetchRequest(entityName: "Restaurant")
    var e: NSError?
    restaurants = managedObjectContext.executeFetchRequest(fetchRequest, error: &e) as [Restaurant]
    if e != nil {
        println("Failed to retrieve record: \(e!.localizedDescription)")
    }
}

import CoreData

class RestaurantTableViewController:UITableViewController, NSFetchedResultsControllerDelegate {

    var fetchResultController:NSFetchedResultsController!

    override func viewDidLoad() {
        super.viewDidLoad()

        var fetchRequest = NSFetchRequest(entityName: "Restaurant")
        let sortDescriptor = NSSortDescriptor(key: "name", ascending: true)
        fetchRequest.sortDescriptors = [sortDescriptor]

        if let managedObjectContext = (UIApplication.sharedApplication().delegate as AppDelegate).managedObjectContext {

            fetchResultController = NSFetchedResultsController(fetchRequest: fetchRequest, managedObjectContext: managedObjectContext, sectionNameKeyPath: nil, cacheName: nil)

            fetchResultController.delegate = self
            var e: NSError?

            var result = fetchResultController.performFetch(&e)
            restaurants = fetchResultController.fetchedObjects as [Restaurant]

            if result != true {
                println(e?.localizedDescription)
            }
        }
    }
}

func controllerWillChangeContent(controller: NSFetchedResultsController!) {
    tableView.beginUpdates()
}

func controller(controller: NSFetchedResultsController!, didChangeObject anObject: AnyObject!, atIndexPath indexPath: NSIndexPath!, forChangeType type: NSFetchedResultsChangeType, newIndexPath: NSIndexPath!) {

    switch type {
        case .Insert:
            tableView.insertRowsAtIndexPaths([newIndexPath], withRowAnimation: .Fade)//注意：第一个参数为[newIndexPath]
        case .Delete:
            tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
        case .Update:
            tableView.reloadRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
        default:
            tableView.reloadData()
    }
    restaurants = controller.fetchedObjects as [Restaurant]
}

func controllerDidChangeContent(controller: NSFetchedResultsController!) {
    tableView.endUpdates()
}

managedObjectContext.deleteObject(restaurantToDelete)

var deleteAction = UITableViewRowAction(style: UITableViewRowActionStyle.Default, title: "Delete",handler: {

    (action:UITableViewRowAction!, indexPath:NSIndexPath!) -> Void in

    // Delete the row from the data source
    if let managedObjectContext = (UIApplication.sharedApplication().delegate as AppDelegate).managedObjectContext {

        let restaurantToDelete = self.fetchResultController.objectAtIndexPath(indexPath) as Restaurant

        managedObjectContext.deleteObject(restaurantToDelete)

        var e: NSError?

        if managedObjectContext.save(&e) != true {
            println("delete error: \(e!.localizedDescription)")
        }

    }
})

searchController = UISearchController(searchResultsController: nil)
searchController.searchResultsUpdater = self//需要实现UISearchResultsUpdating协议
tableView.tableHeaderView = searchController.searchBar
definesPresentationContext = true

searchController = UISearchController(searchResultsController: nil)
searchController.searchBar.sizeToFit()
searchController.searchResultsUpdater = self//需要实现UISearchResultsUpdating协议
tableView.tableHeaderView = searchController.searchBar
definesPresentationContext = true

var searchResults:[Restaurant] = []

func filterContentForSearchText(searchText: String) {

    searchResults = restaurants.filter({ ( restaurant: Restaurant) -> Bool in
        let nameMatch = restaurant.name.rangeOfString(searchText, options: NSStringCompareOptions.CaseInsensitiveSearch)
        let locationMatch = restaurant.location.rangeOfString(searchText, options: NSStringCompareOptions.CaseInsensitiveSearch)
        return nameMatch != nil || locationMatch != nil
    })

}

searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false

func updateSearchResultsForSearchController(searchController: UISearchController) {
    let searchText = searchController.searchBar.text//获取检索字符
    filterContentForSearchText(searchText)//内容过滤
    tableView.reloadData()//更新tableView
}

searchController.searchbar.tintColor //searchbar文字颜色
searchController.searchbar.placeholder //searchbar占位提示字符内容
searchController.searchbar.prompt //位于searchbar上方的文字内容
searchController.searchbar.barTintColor //searchbar背景色

@IBOutlet weak var headingLabel:UILabel!//大标题
@IBOutlet weak var subHeadingLabel:UILabel!//二级标题
@IBOutlet weak var contentImageView:UIImageView!//图片

var index : Int = 0 //索引，标识当前PageContentViewController的索引
var heading : String = ""
var imageFile : String = ""
var subHeading : String = ""

override func viewDidLoad() {
    super.viewDidLoad()
    headingLabel.text = heading
    subHeadingLabel.text = subHeading
    contentImageView.image = UIImage(named: imageFile)
}

class PageViewController: UIPageViewController, UIPageViewControllerDataSource{

    var pageHeadings = ["Personalize", "Locate", "Discover"]//大标题
    var pageImages = ["homei", "mapintro", "fiveleaves"]//图片名称
    var pageSubHeadings = ["Pin your favourite restaurants and create your own food guide", "Search and locate your favourite restaurant on Maps", "Find restaurants pinned by your friends and other foodies around the world"]//二级标题


    override func viewDidLoad() {
        super.viewDidLoad()
        // Set the data source to itself
        dataSource = self
        // Create the first walkthrough screen 创建第一个PageContentView
        if let startingViewController = self.viewControllerAtIndex(0) {
            setViewControllers([startingViewController], direction: .Forward, animated: true, completion: nil)
        }
    }


    //下一个PageContentView
    func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
        var index = (viewController as PageContentViewController).index
        index++
        return self.viewControllerAtIndex(index)
    }

    //上一个PageContentView
    func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
        var index = (viewController as PageContentViewController).index
        index--
        return self.viewControllerAtIndex(index)
    }

    //控制PageContentView的轮询切换
    func viewControllerAtIndex(index: Int) -> PageContentViewController? {
        if index == NSNotFound || index < 0 || index >= self.pageHeadings.count {
            return nil
        }
        // Create a new view controller and pass suitable data.
        if let pageContentViewController =
            storyboard?.instantiateViewControllerWithIdentifier("PageContentViewController") as? PageContentViewController {
            pageContentViewController.imageFile = pageImages[index]
            pageContentViewController.heading = pageHeadings[index]
            pageContentViewController.subHeading = pageSubHeadings[index]
            pageContentViewController.index = index
            return pageContentViewController
        }
        return nil
    }

    /*************************************默认的Page Indicator*********************************************/
    func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
        return pageHeadings.count
    }

    func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
        if let pageContentViewController = storyboard?.instantiateViewControllerWithIdentifier("PageContentViewController") as? PageContentViewController {
            return pageContentViewController.index
        }
        return 0
    }

}

if let pageViewController = storyboard?.instantiateViewControllerWithIdentifier("PageViewController") as? PageViewController {
    self.presentViewController(pageViewController, animated: true, completion: nil)
}

func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
    return pageHeadings.count
}

func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
    if let pageContentViewController = storyboard?.instantiateViewControllerWithIdentifier("PageContentViewController") as? PageContentViewController {
        return pageContentViewController.index
    }
    return 0
}

let defaults = NSUserDefaults.standardUserDefaults()
defaults.setBool(true, forKey: "hasViewedWalkthrough")//存放一个Boolean值，其值为true，键为hasViewedWalkthrough

destinationController.hideBottomBarWhenPushed = true

UITabBar.appearance().tintColor = UIColor(red: 235.0/255.0, green: 75.0/255.0, blue: 27.0/255.0, alpha: 1.0)

UITabBar.appearance().barTintColor = UIColor.blackColor()

UITabBar.appearance().selectionIndicatorImage = UIImage(named: "tabitem_selected")

let url = NSURL(string: "http://www.appcoda.com")
//let url = NSURL(fileURLWithPath: "about.html")
let request = NSURLRequest(URL: url)
webView.loadRequest(request)

import MessageUI

class AboutViewController: UIViewController, MFMailComposeViewControllerDelegate, UINavigationControllerDelegate {

    // 点击后触发写邮件界面
    @IBAction func sendEmail (sender: AnyObject) {
        if MFMailComposeViewController.canSendMail() {
            var composer = MFMailComposeViewController()

            composer.mailComposeDelegate = self
            composer.setToRecipients(["[email protected]"])
            composer.navigationBar.tintColor = UIColor.whiteColor()

            presentViewController(composer, animated: true, completion: {
                UIApplication.sharedApplication().setStatusBarStyle(.LightContent, animated: false)
            })
        }
    }

    func mailComposeController(controller: MFMailComposeViewController!, didFinishWithResult result: MFMailComposeResult, error: NSError!) {

        switch result.value {
            case MFMailComposeResultCancelled.value:
                println("Mail cancelled")
            case MFMailComposeResultSaved.value:
                println("Mail saved")
            case MFMailComposeResultSent.value:
                println("Mail sent")
            case MFMailComposeResultFailed.value:
                println("Failed to send mail: \(error.localizedDescription)")
            default:
                break
        }
        // Dismiss the Mail interface
        dismissViewControllerAnimated(true, completion: nil)
    }
}

let cloudContainer = CKContainer.defaultContainer()
let publicDatabase = CKContainer.defaultContainer().publicCloudDatabase
let predicate = NSPredicate(value: true)
let query = CKQuery(recordType: "Restaurant", predicate: predicate) //Restaurant为在iCloud中创建的Record Type
publicDatabase.performQuery(query, inZoneWithID: nil, completionHandler: { results, error in
// Process the records
})

import CloudKit

var restaurants:[CKRecord] = []
self.getRecordsFromCloud()

func getRecordsFromCloud() {

    // Fetch data using Convenience API
    let cloudContainer = CKContainer.defaultContainer()
    let publicDatabase = CKContainer.defaultContainer().publicCloudDatabase
    let predicate = NSPredicate(value: true)
    let query = CKQuery(recordType: "Restaurant", predicate: predicate) //Restaurant为在iCloud中创建的Record Type
    publicDatabase.performQuery(query, inZoneWithID: nil, completionHandler: { results, error in
        if error == nil {
            println("Completed the download of Restaurant data")
            self.restaurants = results as [CKRecord] //将结果转化为[CKRecord]
            //self.tableView.reloadData() //更新tableView数据源

            // 使用dispatch_async优化代码。在主线程中异步更新tableView数据源
            dispatch_async(dispatch_get_main_queue(), {
                self.tableView.reloadData() //更新tableView数据源
            })

        } else {
            println(error)
        }
    })

}

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    // Return the number of sections.
    return 1
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    // Return the number of rows in the section.
    return restaurants.count
}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell
    // Configure the cell...
    let restaurant = restaurants[indexPath.row]
    cell.textLabel.text = restaurant.objectForKey("name") as? String //获取iCloud中创建的属性为name值

    if (restaurant.objectForKey("image") != nil) {
        let imageAsset = restaurant.objectForKey("image") as CKAsset //获取iCloud中创建的属性为image值并转化为CKAsset
        cell.imageView?.image = UIImage(data: NSData(contentsOfURL: imageAsset.fileURL))
    }
    return cell
}

func getRecordsFromCloud() {

    // Initialize an empty restaurants array
    restaurants = []

    // Get the Public iCloud Database
    let cloudContainer = CKContainer.defaultContainer()
    let publicDatabase = CKContainer.defaultContainer().publicCloudDatabase

    // Prepare the query
    let predicate = NSPredicate(value: true)
    let query = CKQuery(recordType: "Restaurant", predicate: predicate)

    // Create the query operation with the query
    let queryOperation = CKQueryOperation(query: query)
    queryOperation.desiredKeys = ["name", "image"]
    queryOperation.queuePriority = .VeryHigh
    queryOperation.resultsLimit = 50

    queryOperation.recordFetchedBlock = { (record:CKRecord!) -> Void in
        if let restaurantRecord = record {
            self.restaurants.append(restaurantRecord)
        }
    }

    queryOperation.queryCompletionBlock = { (cursor:CKQueryCursor!, error:NSError!) -> Void in
        if (error != nil) {
            println("Failed to get data from iCloud - \(error.localizedDescription)")
        } else {
            println("Successfully retrieve the data from iCloud")

            dispatch_async(dispatch_get_main_queue(), {
                self.tableView.reloadData()
            })
        }
    }

    // Execute the query
    publicDatabase.addOperation(queryOperation)
}

var spinner:UIActivityIndicatorView = UIActivityIndicatorView()
spinner.activityIndicatorViewStyle = .Gray //设置样式为Gray
spinner.center = self.view.center //局中显示
spinner.hidesWhenStopped = true //设置停止的时候可隐藏
self.parentViewController?.view.addSubview(spinner) //添加到父视图控制器中
spinner.startAnimating() //显示UIActivityIndicatorView

dispatch_async(dispatch_get_main_queue(), {
    self.spinner.stopAnimating() //在主线程中调用stopAnimating()隐藏或关闭UIActivityIndicatorView
})

queryOperation.desiredKeys = ["name", "image"]
//修改为
queryOperation.desiredKeys = ["name"]

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell
    if restaurants.isEmpty {
        return cell
    }
    // Configure the cell...
    let restaurant = restaurants[indexPath.row]
    cell.textLabel.text = restaurant.objectForKey("name") as? String

    // Set default image
    cell.imageView.image = UIImage(named: "camera")

    // Fetch Image from Cloud in background
    let publicDatabase = CKContainer.defaultContainer().publicCloudDatabase
    let fetchRecordsImageOperation = CKFetchRecordsOperation(recordIDs: [restaurant.recordID])
    fetchRecordsImageOperation.desiredKeys = ["image"]
    fetchRecordsImageOperation.queuePriority = .VeryHigh
    fetchRecordsImageOperation.perRecordCompletionBlock = {(record:CKRecord!, recordID:CKRecordID!, error:NSError!) ->  Void in
        if (error != nil) {
            println("Failed to get restaurant image: \(error.localizedDescription)")
        } else {
            if let restaurantRecord = record {
                dispatch_async(dispatch_get_main_queue(), { //后台异步加载image
                    let imageAsset = restaurantRecord.objectForKey("image") as CKAsset
                    cell.imageView.image = UIImage(data: NSData(contentsOfURL: imageAsset.fileURL)!)
                })
            }
        }
    }
    publicDatabase.addOperation(fetchRecordsImageOperation)
    return cell
}

var imageCache:NSCache = NSCache()

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell
    if restaurants.isEmpty {
        return cell
    }

    // Configure the cell...
    let restaurant = restaurants[indexPath.row]
    cell.textLabel.text = restaurant.objectForKey("name") as? String

    // Set default image
    cell.imageView.image = UIImage(named: "camera")

    // See if we can get the image from cache 检测Cache中是否存在image
    if let imageFileURL = imageCache.objectForKey(restaurant.recordID) as? NSURL {
        println("Get image from cache")
        cell.imageView.image = UIImage(data: NSData(contentsOfURL: imageFileURL)!)
    } else {
        // Fetch Image from Cloud in background
        let publicDatabase = CKContainer.defaultContainer().publicCloudDatabase
        let fetchRecordsImageOperation = CKFetchRecordsOperation(recordIDs: [restaurant.recordID])
        fetchRecordsImageOperation.desiredKeys = ["image"]
        fetchRecordsImageOperation.queuePriority = .VeryHigh
        fetchRecordsImageOperation.perRecordCompletionBlock = {(record:CKRecord!, recordID:CKRecordID!, error:NSError!) -> Void in
            if (error != nil) {
                println("Failed to get restaurant image: \(error.localizedDescription)")
            } else {
                if let restaurantRecord = record {
                    dispatch_async(dispatch_get_main_queue(), {
                        let imageAsset = restaurantRecord.objectForKey("image") as CKAsset
                        self.imageCache.setObject(imageAsset.fileURL, forKey: restaurant.recordID)
                        cell.imageView.image = UIImage(data: NSData(contentsOfURL: imageAsset.fileURL)!)
                    })
                }
            }
        }
        publicDatabase.addOperation(fetchRecordsImageOperation)
    }
    return cell
}