ios - UIWebView webViewDidStartLoad 方法未在 swift 中调用

Question

我在ios中实现了一个简单的webview，并显示PDF，我想做两件事: 1-当 pdf 文档显示在 web View 上时，删除它周围的灰色填充区域 2-在给定按钮坐标的 pdf 文件上的特定位置显示按钮

对于上述两个问题，我在 SO 上找到了代码并将其更改为我的需要。这是我到目前为止的代码( View Controller )

class DocAreaController: UIViewController, UIWebViewDelegate{


@IBOutlet var myWebView: UIWebView!


override func viewDidLoad() {
    super.viewDidLoad()

    myWebView.scrollView.scrollEnabled = false
    myWebView.scrollView.bounces = false
    myWebView.scrollView.pagingEnabled = true
    myWebView.userInteractionEnabled = true
    myWebView.delegate = self

    func webViewDidStartLoad(myWebView: UIWebView){
        let paddingScript = "document.body.style.margin='0';document.body.style.padding = '0'"
        let result = myWebView.stringByEvaluatingJavaScriptFromString(paddingScript)
        debugPrint("method called")

        let btn: UIButton = UIButton(frame: CGRectMake(188, 340, 46, 30))
        btn.backgroundColor = UIColor.cyanColor() //.colorWithAlphaComponent(0.5)
        btn.userInteractionEnabled = false
        btn.tag = 1               // change tag property
        myWebView.addSubview(btn) // add to view as subview

    }


    // Get the document's file path.
    let filepath = (NSBundle.mainBundle().pathForResource("Reader", ofType: "pdf"))! as String

    // Create an NSURL object based on the file path.
    let url = NSURL.fileURLWithPath(filepath)

    // Create an NSURLRequest object.
    let request = NSURLRequest(URL: url)

    // Load the web viewer using the request object.
    myWebView.loadRequest(request)

}

}

但是 webViewDidStartLoad 方法没有被调用。我已经在代码和 Storyboard中设置了 webview 的委托(delegate)。我错过了什么？

Answer 1

将 webViewDidStartLoad 移出 viewDidLoad 方法。将其放在 viewDidLoad 之后，它应该可以工作。

override func viewDidLoad() {
    super.viewDidLoad()

    myWebView.scrollView.scrollEnabled = false
    myWebView.scrollView.bounces = false
    myWebView.scrollView.pagingEnabled = true
    myWebView.userInteractionEnabled = true
    myWebView.delegate = self

    // Get the document's file path.
    let filepath = (NSBundle.mainBundle().pathForResource("Reader", ofType: "pdf"))! as String

    // Create an NSURL object based on the file path.
    let url = NSURL.fileURLWithPath(filepath)

    // Create an NSURLRequest object.
    let request = NSURLRequest(URL: url)

    // Load the web viewer using the request object.
    myWebView.loadRequest(request)

}


func webViewDidStartLoad(myWebView: UIWebView){
        let paddingScript = "document.body.style.margin='0';document.body.style.padding = '0'"
        let result = myWebView.stringByEvaluatingJavaScriptFromString(paddingScript)
        debugPrint("method called")

        let btn: UIButton = UIButton(frame: CGRectMake(188, 340, 46, 30))
        btn.backgroundColor = UIColor.cyanColor() //.colorWithAlphaComponent(0.5)
        btn.userInteractionEnabled = false
        btn.tag = 1               // change tag property
        myWebView.addSubview(btn) // add to view as subview

    }