Question

我在UIWebView顶部创建了一个按钮，我想用它来按下时刷新webview。以下代码位于我的ViewController类中：

@IBOutlet weak var webView: UIWebView!

override func shouldAutorotate() -> Bool {
    return false
}

override func supportedInterfaceOrientations() -> UIInterfaceOrientationMask {
    return UIInterfaceOrientationMask.Landscape
}

override func viewDidLoad() {
    super.viewDidLoad()
    let webView:UIWebView = UIWebView(frame: CGRectMake(30, 20, UIScreen.mainScreen().bounds.width, UIScreen.mainScreen().bounds.height))
    let button = UIButton(type: .System)

    webView.scalesPageToFit = true
    webView.multipleTouchEnabled = true
    webView.backgroundColor = UIColor.whiteColor()
    webView.loadRequest(NSURLRequest(URL: NSURL(string: "http://www.example.com")!))
    self.view.addSubview(webView)

    button.frame = CGRectMake(20, -20, 100, 100)
    button.setTitle("Refresh", forState: UIControlState.Normal)
    button.addTarget(self, action: Selector(reload()), forControlEvents: UIControlEvents.TouchUpInside)
    webView.insertSubview(button, aboveSubview: webView)
}

func reload() {
    webView.reload()
}

我创建了reload方法来刷新webView，但单击按钮时没有任何反应。我还尝试在viewDidLoad中创建重载方法，看看是否解决了这个问题。可能导致这个问题的原因是什么？

Answer 1

您在视图中定义了webview确实加载范围，将其取出：

let webView:UIWebView = UIWebView(frame: CGRectMake(30, 20, UIScreen.mainScreen().bounds.width, UIScreen.mainScreen().bounds.height))

func viewDidLoad() {
    super.viewDidLoad()
    let button = UIButton(type: .System)

    webView.scalesPageToFit = true
    webView.multipleTouchEnabled = true
    webView.backgroundColor = UIColor.whiteColor()
    webView.loadRequest(NSURLRequest(URL: NSURL(string: "http://www.example.com")!))
    webView.layer.zPosition = 1
    self.view.addSubview(webView)

    button.frame = CGRectMake(0, 0, 100, 100)
    button.setTitle("Reload Page", forState: UIControlState.Normal)
    button.addTarget(self, action: Selector(reload()), forControlEvents: UIControlEvents.TouchUpInside)
    webView.insertSubview(button, aboveSubview: webView)
}

func reload() {
    webView.reload()
}

Answer 2

action: Selector(reload())

语法错误。在Xcode 7.2及以下版本中，它应该是

action: Selector("reload")

在Xcode 7.3及以上它应该是

action: #selector(ClassName.funcName)

在Xcode 7.2中，整个事情应该是

let webView:UIWebView = UIWebView(frame: CGRectMake(30, 20, UIScreen.mainScreen().bounds.width, UIScreen.mainScreen().bounds.height))

override func viewDidLoad() {
    super.viewDidLoad()

    let button = UIButton(type: .System)

    webView.scalesPageToFit = true
    webView.multipleTouchEnabled = true
    webView.backgroundColor = UIColor.whiteColor()
    webView.loadRequest(NSURLRequest(URL: NSURL(string: "http://www.example.com")!))
    self.view.addSubview(webView)

    button.frame = CGRectMake(20, -20, 100, 100)
    button.setTitle("Refresh", forState: UIControlState.Normal)
    button.addTarget(self, action: Selector("reload"), forControlEvents: .TouchUpInside)
    webView.insertSubview(button, aboveSubview: webView)
}

func reload() {
    webView.reload()
}

用于重新加载UIWebView的按钮

2 个答案: