我正在学习iOS。而现在iOS上的本地数据库。我来自Android，发现本地数据库有点难以理解。我写了一个问题，给了我几张投票（而不是简单地使用CoreStore或Sync或MagicalRecord）。然后我开始阅读this tutorial。下载示例项目后，我在Redundant conformance of 'BeerListViewController' to protocol 'UITableViewDataSource'中收到BeerListViewController错误。请告诉我如何才能解决它。
以下是代码：
import UIKit
import Foundation
class BeerListViewController: UITableViewController {
@IBOutlet weak var sortByControl: UISegmentedControl!
@IBOutlet weak var searchBar: UISearchBar!
let sortKeyName = "name"
let sortKeyRating = "beerDetails.rating"
let wbSortKey = "wbSortKey"
//------------------------------------------
// Rating
var amRatingCtl: AnyObject!
let beerEmptyImage: UIImage = UIImage(named: "beermug-empty")!
let beerFullImage: UIImage = UIImage(named: "beermug-full")!
//#####################################################################
// MARK: - Initialization
required init(coder aDecoder: NSCoder) {
// Automatically invoked by UIKit as it loads the view controller from the storyboard.
amRatingCtl = AMRatingControl(location: CGPointMake(190, 10),
emptyImage: beerEmptyImage,
solidImage: beerFullImage,
andMaxRating: 5)
// A call to super is required after all variables and constants have been assigned values but before anything else is done.
super.init(coder: aDecoder)!
}
//#####################################################################
// MARK: - Segues
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Allows data to be passed to the new view controller before the new view is displayed.
// "destinationViewController" must be cast from its generic type (AnyObject) to the specific type used in this app
// (BeerDetailViewController) before any of its properties can be accessed.
let controller = segue.destinationViewController as? BeerDetailViewController
if segue.identifier == "editBeer" {
controller!.navigationItem.rightBarButtonItems = []
//------------------------------------------------------------------------------------
} else if segue.identifier == "addBeer" {
controller!.navigationItem.leftBarButtonItem = UIBarButtonItem(title: "Cancel",
style: UIBarButtonItemStyle.Plain,
target: controller,
action: "cancelAdd")
controller!.navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Done",
style: UIBarButtonItemStyle.Done,
target: controller,
action: "addNewBeer")
}
}
//#####################################################################
// MARK: - UIViewController - Responding to View Events
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
//------------------------------------------
// Sorting Key
if !(NSUserDefaults.standardUserDefaults().objectForKey(wbSortKey) != nil) {
// User's sort preference has not been saved. Set default to sort by rating.
NSUserDefaults.standardUserDefaults().setObject(sortKeyRating, forKey: wbSortKey)
}
// Keep the sort control in the UI in sync with the means by which the list is sorted.
if NSUserDefaults.standardUserDefaults().objectForKey(wbSortKey) as! String == sortKeyName {
sortByControl.selectedSegmentIndex = 1
}
//------------------------------------------
fetchAllBeers()
// Cause tableView(cellForRowAtIndexPath) to be called again for every visible row in order to update the table.
tableView.reloadData()
}
//#####################################################################
// MARK: - UIViewController - Managing the View
// viewDidLoad() is called after prepareForSegue().
override func viewDidLoad() {
super.viewDidLoad()
//------------------------------------------
tableView.contentOffset = CGPointMake(0, 44)
}
//#####################################################################
// MARK: - Action Methods
@IBAction func sortByControlChanged(sender: UISegmentedControl) {
switch sender.selectedSegmentIndex {
case 0:
NSUserDefaults.standardUserDefaults().setObject(sortKeyRating, forKey: wbSortKey)
fetchAllBeers()
tableView.reloadData()
case 1:
NSUserDefaults.standardUserDefaults().setObject(sortKeyName, forKey: wbSortKey)
fetchAllBeers()
tableView.reloadData()
default:
break
}
}
//#####################################################################
// MARK: - MagicalRecord Methods
func fetchAllBeers() {
}
//#####################################################################
func saveContext() {
}
//#####################################################################
}
//#####################################################################
// MARK: - Table View Data Source
extension BeerListViewController: UITableViewDataSource { // THE ERROR APPEARS HERE
//#####################################################################
// MARK: Configuring a Table View
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
//#####################################################################
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 10
}
//#####################################################################
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cellIdentifier = "Cell"
let cell = tableView.dequeueReusableCellWithIdentifier(cellIdentifier)
configureCell(cell!, atIndex: indexPath)
return cell!
}
//#####################################################################
// MARK: Helper Methods
func configureCell(cell: UITableViewCell, atIndex indexPath: NSIndexPath) {
//------------------------------------------
// Rating
let ratingText = ""
let myRect = CGRect(x:250, y:0, width:200, height:50)
var ratingLabel = UILabel(frame: myRect)
if !(cell.viewWithTag(20) != nil) {
ratingLabel.tag = 20
ratingLabel.text = ratingText
cell.addSubview(ratingLabel)
} else {
ratingLabel = cell.viewWithTag(20) as! UILabel
}
//----------------------
ratingLabel.text = ratingText
}
//#####################################################################
// MARK: Inserting or Deleting Table Rows
override func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -> Bool {
return true
}
//#####################################################################
override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
// When the commitEditingStyle method is present in a view controller, the table view will automatically enable swipe-to-delete.
if (editingStyle == .Delete) {
}
}
//#####################################################################
}
//#####################################################################
// MARK: - Search Bar Delegate
extension BeerListViewController: UISearchBarDelegate {
// MARK: Editing Text
func searchBar(searchBar: UISearchBar, textDidChange searchText: String) {
if searchBar.text != "" {
performSearch()
} else {
fetchAllBeers()
tableView.reloadData()
}
}
//#####################################################################
func searchBarTextDidBeginEditing(searchBar: UISearchBar) {
searchBar.showsCancelButton = true
}
//#####################################################################
// MARK: Clicking Buttons
func searchBarCancelButtonClicked(searchBar: UISearchBar) {
searchBar.resignFirstResponder()
searchBar.text = ""
searchBar.showsCancelButton = false
fetchAllBeers()
tableView.reloadData()
}
//#####################################################################
func searchBarSearchButtonClicked(searchBar: UISearchBar) {
// This method is invoked when the user taps the Search button on the keyboard.
searchBar.resignFirstResponder()
performSearch()
}
//#####################################################################
// MARK: Helper Methods
func performSearch() {
tableView.reloadData()
}
//#####################################################################
// MARK: - Bar Positioning Delegate
// UISearchBarDelegate Protocol extends UIBarPositioningDelegate protocol.
// Method positionForBar is part of the UIBarPositioningDelegate protocol.
// This delegate method is required to prevent a gap between the top of the screen and the search bar.
// That happens because, as of iOS 7, the status bar is no longer a separate area but is directly drawn on top of the view controller.
func positionForBar(bar: UIBarPositioning) -> UIBarPosition {
// Tell the search bar to extend under the status bar area.
return .TopAttached
}
//#####################################################################
}
答案 0 :(得分：0)
UITableViewController符合UITableViewDataSource。
删除协议一致性
extension BeerListViewController { ...