How to cancel a UIWebView?

问题

I'm modally presenting a UIViewController with a UIWebView as its view. How do I dismiss the UIWebView when the user hits a cancel button on it?

One idea I have is to have the cancel button link to http://cancel and then check in

- (void)webViewDidStartLoad:(UIWebView *)webView

If webView.request.URL.host isEqualToString:@"cancel", then dismiss the view controller.

Does the host have to have a dot in it, e.g., "cancel.com"?

回答1:

You're on the right path, but you're approach is slightly off. You don't need or want this to be an HTTP URL. Make your URL cancel:.

<a href="cancel:">Thing to click</a>

Then implement webView:shouldStartLoadWithRequest:navigationType: in your web view delegate. Something like this (untested):

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {
    if ([request.URL.scheme isEqualToString:@"cancel"]) {
        [self dismissModalViewControllerAnimated:YES];
        return NO;
    }
    return YES;
}

回答2:

It's not entirely clear if you want to stop loading in a web view or just dismiss the modal view controller that's containing it.

To stop loading:

[webView stopLoading];

To dismiss the view controller:

[self dismissModalViewControllerAnimated:YES];

Don't forget to set the web view's delegate to nil before you release it.

来源：https://stackoverflow.com/questions/7109639/how-to-cancel-a-uiwebview