Question

我的iOS天气应用程序出现问题。我是xCode编程的新手，所以这可能是一个愚蠢的错误。无论如何，问题是：我试图在我的单页应用程序中添加刷新按钮。该按钮具有关联的IBAction功能，因此当按下该按钮时，它应该被隐藏并且活动指示器应该出现。这就是功能：

@IBAction func reload（）{

    refreshButton.hidden = true
    refreshActivityIndicator.hidden = false
    refreshActivityIndicator.startAnimating()

}

这就是变量的声明：

@IBOutlet weak var refreshButton: UIButton!

@IBOutlet weak var refreshActivityIndicator: UIActivityIndicatorView!

当我运行应用程序并按下刷新按钮时，应用程序崩溃，我收到此错误：

@UIApplicationMain class AppDelegate：UIResponder，UIApplicationDelegate {＆lt; - thread 1 signal sigarbt

控制台没有显示任何其他内容。可能是什么问题？

// APPDELEGATE.SWIFT

导入UIKit

@UIApplicationMain class AppDelegate：UIResponder，UIApplicationDelegate {

var window: UIWindow?


func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    // Override point for customization after application launch.

    application.setStatusBarHidden(true, withAnimation: .None)

    return true
}

func applicationWillResignActive(application: UIApplication) {
    // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
    // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
}

func applicationDidEnterBackground(application: UIApplication) {
    // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
    // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
}

func applicationWillEnterForeground(application: UIApplication) {
    // Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
}

func applicationDidBecomeActive(application: UIApplication) {
    // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
}

func applicationWillTerminate(application: UIApplication) {
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}

}

// VIEWCONTROLLER.SWIFT 导入UIKit 进口基金会

类ViewController：UIViewController {

private let apiKey = "447073dc853014a6fa37376c43d8462b"

@IBOutlet weak var iconView: UIImageView!
@IBOutlet weak var currentTimeLabel: UILabel!
@IBOutlet weak var temperatureLabel: UILabel!
@IBOutlet weak var humidityLabel: UILabel!
@IBOutlet weak var precipitationLabel: UILabel!
@IBOutlet weak var summaryLabel: UILabel!

@IBOutlet weak var refreshButton: UIButton!

@IBOutlet weak var refreshActivityIndicator: UIActivityIndicatorView!


override func viewDidLoad() {

    super.viewDidLoad()

    // Do any additional setup after loading the view, typically from a nib.

    refreshActivityIndicator.hidden = true

    // base URL

    let baseURL = NSURL(string: "https://api.forecast.io/forecast/\(apiKey)/")

    // add coordinates to base url (API syntax)

    let forecastURL = NSURL(string: "44.698150,10.656846", relativeToURL: baseURL)

    // NSURL SESSION 
    //The NSURLSession class and related classes provide an API for downloading content via HTTP. This API provides a rich set of delegate methods for supporting authentication and gives your app the ability to perform background downloads when your app is not running or, in iOS, while your app is suspended. With the NSURLSession API, your app creates a series of sessions, each of which coordinates a group of related data transfer tasks. For example, if you are writing a web browser, your app might create one session per tab or window. Within each session, your app adds a series of tasks, each of which represents a request for a specific URL (and for any follow-on URLs if the original URL returned an HTTP redirect).

    let sharedSession = NSURLSession.sharedSession()



    let downloadTask : NSURLSessionDownloadTask = sharedSession.downloadTaskWithURL(forecastURL!, completionHandler:

        { (location: NSURL!, response: NSURLResponse!, error: NSError!) -> Void in

        if (error == nil) {

            let dataObject = NSData(contentsOfURL: location) // convert in NSData object

            // serialize NSData object in Json as Dictionary

            let weatherDictionary: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataObject!, options: nil, error: nil) as NSDictionary

            // instance of Current (Current.swift) init with weatherDictionary

            let currentWeather = Current(weatherDictionary: weatherDictionary)


            // we put the code in the main queue cause this is relative the UI, that have the first thread (concurrency)

            dispatch_async(dispatch_get_main_queue(), { () -> Void in

                self.temperatureLabel.text = "\(currentWeather.temperature)"
                self.iconView.image = currentWeather.icon!
                self.currentTimeLabel.text = "At \(currentWeather.currentTime!) it is"
                self.humidityLabel.text = "\(currentWeather.humidity)"
                self.precipitationLabel.text = "\(currentWeather.precipProbability)"
                self.summaryLabel.text = "\(currentWeather.summary)"

                // Stop refresh animation

                self.refreshActivityIndicator.stopAnimating()
                self.refreshActivityIndicator.hidden = true
                self.refreshButton.hidden = false

            })

        }


    })

    downloadTask.resume() // call sharedSession.downloadTaskWithURL -> store json data in location (local temporary memory)


}


@IBAction func reload() {
    println("PRESSED")
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

}

我还没有.h或.m文件。

Answer 1

重载功能是否被调用？如果您使用storyboard / Xib创建UIButton，那么在touchUpInside Event上链接Xib中的重载函数，或者如果您在代码中创建UIButton事件，则如下所示：

在.h文件中创建另一个UIButton属性： @property（非原子，强）UIButton *刷新;

在.m文件中

-(void) viewDidLoad {
self.refresh = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[self.refresh addTarget:self 
       action:@selector(reload:) forControlEvents:UIControlEventTouchUpInside];
[self.refresh setTitle:@"Reload" forState:UIControlStateNormal];
self.refresh .frame = CGRectMake(80.0, 210.0, 160.0, 40.0);
[self.view addSubview:self.refresh];
}


-(void) reload:(UIButton*)sender
{
    NSLog(@"you clicked on button %@", sender.tag);
    if(self.refresh.hidden) {
        self.refresh.hidden = false;
    } else {
        self.refresh.hidden = true;
    }
}

Answer 2

好的，它有效！请不要问我为什么:) 我只是删除了代码并重写了它。它有效。称之为魔术。谢谢大家的答案。

按下重新加载按钮时应用程序崩溃

2 个答案: