Ios 没有生成错误，但在模拟器中崩溃。

我没有得到构建错误，但一旦我在模拟器中按下右上角的+键添加新的url，程序就会崩溃。这是我得到的错误：

2017-02-21 09:37:48.667收藏夹网站[2211:128142]->[Favorite_网站。MasterViewController AddButton按下：]：发送到实例0x7ff266408aa0的无法识别的选择器 2017-02-21 09:37:48.672收藏夹网站[2211:128142]*由于未捕获的异常“NSInvalidArgumentException”而终止应用程序，原因：'-[Favorite_Websites.MasterViewController AddButton Pressed:::]：未识别的选择器发送到实例0x7ff266408aa0' *第一次抛出调用堆栈： ( 0 CoreFoundation 0x000000010d0b0d4b异常预处理+171 1 libobjc.A.dylib 0x000000010cb1221e objc_异常_抛出+48 2 CoreFoundation 0x000000010d120f04-[NSObject（NSObject）不识别选择器：][132 3 CoreFoundation 0x000000010d036005\uuuuuuuuu转发 4 CoreFoundation 0x000000010d035b88\u CF\u转发\u准备\u 0+120 5 UIKit 0x000000010d4d68bc-[UIApplication sendAction:to:from:forEvent:+83 6 UIKit 0x000000010d9184a1-[UIBarButtonItem（UIInternal）\发送操作：withEvent:+149 7 UIKit 0x000000010d4d68bc-[UIApplication sendAction:to:from:forEvent:+83 8 UIKit 0x000000010d65cc38-[UIControl发送操作：发送到：forEvent:+67 9 UIKit 0x000000010d65cf51-[UIControl\u发送操作预防：withEvent:+444 10 UIKit 0x000000010d65d0db-[UIControl\u发送操作预防：带事件：][838 11 UIKit 0x000000010d65be4d-[UIControl触摸附加：withEvent:][668 12 UIKit 0x000000010d544545-[UIWindow\u sendTouchesForEvent:+2747 13 UIKit 0x000000010d545c33-[UIWindow sendEvent:+4011 14 UIKit 0x000000010d4f29ab-[UIApplication sendEvent:+371 15 UIKit 0x000000010dcdf72dDispatchPreprecedEventFromeEventQueue+3248 16 UIKit 0x000000010dcd8463_u handleEventQueue+4879 17 CoreFoundation 0x000000010d055761\uu CFRUNLOOP\u正在调用\u OUT\u以执行\u SOURCE0\u函数+17 18 CoreFoundation 0x000000010d03a98c\uu CFRunLoopDoSources0+556 19 CoreFoundation 0x000000010d039e76 _ucfrunlooprun+918 20 CoreFoundation 0x000000010d039884 CFRunLoopRunSpecific+420 21图形服务0x000000011173fa6f GSEventRunModal+161 22 UIKit 0x000000010d4d4c68 UIApplicationMain+159 23个常用网站0x000000010c516e0f main+111 24 libdyld.dylib 0x00000001107af68d启动+1 ) libc++abi.dylib:以NSException类型的未捕获异常终止 （lldb）

以下是错误来源的MasterViewController.swift代码

class MasterViewController: UITableViewController, ModelDelegate {

    var detailViewController: DetailViewController? = nil


    var model: Model! = nil // manages the app's data

    // conform to ModelDelegate protocol; updates view wehn model changes
    func modelDataChanged(){
        tableView.reloadData() // reload the UITableView
    }

    // called after the view loads for further UI configuration
    override func viewDidLoad() {
        super.viewDidLoad()

        // set up left and right UIBarButtonItems
        self.navigationItem.leftBarButtonItem = self.editButtonItem

        let addButton = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: Selector(("addButtonPressed:")))
        self.navigationItem.rightBarButtonItem = addButton

        if let split = self.splitViewController {
            let controllers = split.viewControllers
            self.detailViewController = (controllers[controllers.count-1] as! UINavigationController).topViewController as? DetailViewController
        }

        model = Model(delegate: self) // create the Model
        model.synchronize() // tell model to sync its data

    }

    // displays a UIAlertController to obtain new url from user

    func addButtonPressed(sender: AnyObject) {
        displayAddEditurlSearchAlert(isNew: true, index: nil)
    }

    // handles long press for editing or sharing a url
    func tableViewCellLongPressed(
        sender: UILongPressGestureRecognizer){
        if sender.state == UIGestureRecognizerState.began &&
            !tableView.isEditing {
            let cell = sender.view as! UITableViewCell // get cell

            if let indexPath = tableView.indexPath(for: cell) {
                displayLongPressOptions(row: indexPath.row)
            }
        }
    }

    // displays the edit/share options
    func displayLongPressOptions(row: Int){
        // create UIAlertController for user input
        let alertController = UIAlertController(title: "Options",
                                                message: "Edit or Share your url",
                                                preferredStyle: UIAlertControllerStyle.alert)

        // create Cancel action
        let cancelAction = UIAlertAction(title: "Cancel",
                                         style: UIAlertActionStyle.cancel, handler: nil)
        alertController.addAction(cancelAction)

        let editAction = UIAlertAction(title: "Edit",
                                       style: UIAlertActionStyle.default,
                                       handler: {(action) in
                                        self.displayAddEditurlSearchAlert(isNew: false, index: row)})
        alertController.addAction(editAction)

        let shareAction = UIAlertAction(title: "Share",
                                        style: UIAlertActionStyle.default,
                                        handler: {(action) in self.shareurlSearch(index: row)})
        alertController.addAction(shareAction)
        present(alertController, animated: true,
                              completion: nil)
    }

    // displays add/edit dialog
    func displayAddEditurlSearchAlert(isNew: Bool, index: Int?){
        // create UIAlertController for user input
        let alertController = UIAlertController(
            title: isNew ? "Add URL" : "Edit URL",
            message: isNew ? "" : "Modify your URL",
            preferredStyle: UIAlertControllerStyle.alert)

        // create UITextFields in which user can enter a new URL
        alertController.addTextField(
            configurationHandler: {(textField) in
                if isNew {
                    textField.placeholder = "Enter URL"
                }else{
                    textField.text = self.model.queryForTagAtIndex(index: index!)
                }
        })

        alertController.addTextField(
            configurationHandler: {(textField) in
                if isNew {
                    textField.placeholder = "Tag your URL"
                }else {
                    textField.text = self.model.tagAtIndex(index: index!)
                    textField.isEnabled = false
                    textField.textColor = UIColor.lightGray
                }
        })

        // create Cancel action
        let cancelAction = UIAlertAction(title: "Cancel",
                                         style: UIAlertActionStyle.cancel, handler: nil)
        alertController.addAction(cancelAction)

        let saveAction = UIAlertAction(title: "Save",
                                       style: UIAlertActionStyle.default,
                                       handler: {(action) in
                                        let query =
                                            ((alertController.textFields?[0])! as UITextField).text
                                        let tag =
                                            ((alertController.textFields?[1])! as UITextField).text

                                        // ensure query and tag are not empty
                                        if !query!.isEmpty && !tag!.isEmpty {
                                            self.model.saveQuery(
                                                query: query!, forTag: tag!, syncToCloud: true)

                                            if isNew {
                                                let indexPath =
                                                IndexPath(row: 0, section: 0)
                                                self.tableView.insertRows(at: [indexPath],
                                                                          with: .automatic)
                                            }
                                        }
        })
        alertController.addAction(saveAction)

        present(alertController, animated: true,
                              completion: nil)

    }

    // displays share sheet
    func shareurlSearch(index: Int) {
        let message = "Check out this cool Web site"
        let urlString = urlEncodeString(string: model.queryForTagAtIndex(index: index)!)
        let itemsToShare = [message, urlString]

        // create UIActivityViewController so user can share url
        let activityViewController = UIActivityViewController(
            activityItems: itemsToShare, applicationActivities: nil)
        present(activityViewController,
                              animated: true, completion: nil)
    }

        // MARK: - Segues


    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "showDetail" {
            if let indexPath = self.tableView.indexPathForSelectedRow {

                let controller = (segue.destination as! UINavigationController).topViewController as! DetailViewController

                // get query String
                let query = String(model.queryForTagAtIndex(index: indexPath.row)!)

                // create NSURL to perfrom url search

                controller.detailItem = NSURL(string: urlEncodeString(string: query!))
                controller.navigationItem.leftBarButtonItem = self.splitViewController?.displayModeButtonItem
                controller.navigationItem.leftItemsSupplementBackButton = true
            }
        }
    }

    // returns a URL encoded version of the query String
    func urlEncodeString(string: String) -> String {
        return string.addingPercentEncoding(
            withAllowedCharacters: NSCharacterSet.urlQueryAllowed)!
    }

    // MARK: - Table View
    // callback that returns total number of sections in UITableView
    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

    // callback that returns number of rows in the UITableView
    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return model.count
    }

    // callback that returns a configured cell for the given NSIndexPath
    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

        // get cell
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as UITableViewCell

        // set up long press guesture recognier
        cell.textLabel!.text = model.tagAtIndex(index: indexPath.row)

        // set up long press guesture recognizer
        let longPressGestureRecognizer = UILongPressGestureRecognizer(
            target: self, action: Selector(("tableViewCellLongPressed:")))
        longPressGestureRecognizer.minimumPressDuration = 0.5
        cell.addGestureRecognizer(longPressGestureRecognizer)

        return cell
    }

    //callback that return whether a cell is editable
    override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
        // Return false if you do not want the specified item to be editable.
        return true // all cells are editable
    }

    // callback that deletes a row from the UITableView
    override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
        if editingStyle == .delete {
            model.deleteurlSearchAtIndex(index: indexPath.row)

            // remove UITableView row
            tableView.deleteRows(at: [indexPath], with: .fade)
        }
    }
    // callback that returns whether cells can be moved
    override func tableView(_ tableView: UITableView, canMoveRowAt indexPath: IndexPath) -> Bool {
            return true
        }

    // callback that reorders keys when user moves them in the table
    override func tableView(_ tableView: UITableView, moveRowAt sourceIndexPath: IndexPath,
                            to destinationIndexPath: IndexPath) {
        // tell model to reorder tags based on UITableView order
        model.moveTagAtIndex(oldIndex: sourceIndexPath.row,
                             toDestinationIndex: destinationIndexPath.row)
    }

}

---

问题在于这个表达式：

Selector(("addButtonPressed:"))

替换为：

#selector(addButtonPressed)

---

请尝试清理生成文件夹并重新启动Xcode

我不确定您是否需要DetailViewController.swift或Model.swift文件，但如果需要，我可以提供它们。请检查情节提要中的按钮，并查看addButtonPressed链接是否存在，以及该确切名称。在“无法识别的选择器”上进行搜索。这是非常常见的问题，在这里已经被很好地讨论过了。我投票将这个问题作为离题题结束，因为它是所有其他“未识别的选择器”问题的重复。例如，请参见我在这里的回答：这完全相同。您没有完全按照我说的（或您声称的）进行替换。如果你按照我说的做了，那么这行代码现在会变成

let addButton=UIBarButtonItem（barbuttonsystem:.add，target:self，action:#selector（addButtonPressed））

。显然不是。当我将代码更改为这个时，模拟器将不会加载。它只是停止并将我带到这里：->0x10af51dcc:movq-0x88（%rbp），%rdi并显示线程1:断点2.1。它不会给我任何其他错误，也不会像以前那样说明终止。这是因为您创建了一个断点，现在我们正在暂停它。这与这个问题无关。对不起，我对这个问题一无所知。谢谢你指出这一点。我花了点时间才弄明白那些是什么。这似乎现在起作用了。