UIWebViewDelegate: webViewDidFinishLoad not called

问题:

I have an app where users can navigate a pile of locally stored HTML files. I have a UIWebView, configured up correctly with a UIWebViewDelegate. Usually, when the user follows a link, shouldStartLoadWithRequest is called, followed by webViewDidFinishLoad a bit later.

But, if the link is pointing to an anchor on the same page as the one which is currently displayed, only shouldStartLoadWithRequest is called. webViewDidFinishLoad does not fire.

In a sense, I see that this might be expected behaviour, because in-page navigation should not require a page reload. However, I really need a place to hook into the call stack after in-page navigation is complete. The optimal solution would let me know when any sort of navigation has ended, both from another page, in-page and forward/backward actions.

My best hackaround so far has been to call performSelector: withObject: afterDelay: at the end of my shouldStartLoadWithRequest method, but I'm not happy with this.

Does anyone know how I can solve this correctly? Any insight appreciated!

回答1:

You can try to use NSURLConnectionDataDelegate, it allows you to handle incoming data. Maybe you can determine if the page is loaded manually by adding a sign to your html files.

NSURLConnectionDataDelegate Reference

Edit: gist.github.com/buranmert/7304047 I wrote a piece of code and it worked, that may not be the way you wanted it to work but maybe it helps. Every time user clicks a URL with anchor, it creates another connection and as connection finishes loading web view loads the data, that marks the point where web view finished loading the page. As you use only local html files, I do not think creating connections will create problems

回答2:

What you are describing is intended behavior. Just as AJAX or resource requests are never passed to the delegate, only root page changes will ever hit webViewDidFinishLoad:. But I have good news, and it doesn't involve saving a bunch of money on car insurance.

Loads performed within an iFrame DO trigger the full delegate methods and this gives you a solution. You can use this mechanism to post a notification to the native code, just as is often done for console.log() as described in this post. Alternatively, Native Bridge would work well to call into your Objective C code from JavaScript.

回答3:

Just check weather u got the delegate function DidStartLoading if it is called no doubt that DidFinish also should get called

回答4:

Are you sure your shouldStartLoadWithRequest always returns an YES???

I always add

return YES;

at the end of shouldStartLoadWithRequest implementation.And that works for me. By returning YES, it denotes that the webview has loaded and would call the webViewDidFinishLoad

回答5:

if([webView isLoading]==1)
{
    //your webview is loading
}
else
{
   //your webview has loaded
}

回答6:

Here is a Swift Implementation of Mert Buran's code incase anybody is looking for it. (Although NSURLConnection is deprecated as of iOS 9)

But it does not solve my problem. When i click on a jquery link that popups a video, it does not fire the webViewDidFinishLoad.

class WebViewController: UIViewController, UIWebViewDelegate, NSURLConnectionDelegate {

var menuURL: String?

var response: NSURLResponse?
var data = NSData()

// MARK: Properties
@IBOutlet weak var webView: UIWebView!

override func viewDidLoad() {
    super.viewDidLoad()

    webView.delegate = self

    // From Web
    let url = NSURL (string: menuURL!)
    let urlRequest = NSURLRequest(URL: url!)

    let connection = NSURLConnection(request: urlRequest, delegate: self)
    self.data = NSData()
    connection!.start()

    // if this is false, page will be 'zoomed in' to normal size
    webView.scalesPageToFit = false

}

func webView(webView: UIWebView, shouldStartLoadWithRequest request: NSURLRequest, navigationType: UIWebViewNavigationType) -> Bool {
    if navigationType == .LinkClicked && request.URL!.fragment != nil {
        let connection = NSURLConnection(request: request, delegate: self)
        connection!.start()
        return false
    }
    return true
}

func connection(connection: NSURLConnection, didReceiveResponse response: NSURLResponse) {
    self.response = response
}

func connection(connection: NSURLConnection, didReceiveData data: NSData) {
    let oldData = NSMutableData(data: self.data)
    oldData.appendData(data)
    self.data = oldData
}

func connectionDidFinishLoading(connection: NSURLConnection) {
    self.webView.loadData(self.data, MIMEType: self.response!.MIMEType!, textEncodingName: "utf-8", baseURL: self.response!.URL!)
    self.data = NSData()
}


}