Question

Is it possible to use a progress bar with a UIWebView when loading web pages, as Safari does in the address bar? I read that you need to use a private API, which Apple doesn’t allow, but that doesn’t seem right… you can’t detect how large a page is and update the progress bar with the amount downloaded?

Answer 1

For this kind of thing, you can only really ‘detect’ page size by using Content-Length headers, but otherwise you can still present a loading control (like one of the moving zebra crossing type bars which doesn’t show a discrete % progress but shows that activity is occurring.. or even just a UIActivityIndicator). You could try a ready-made class like ASIWebPageRequest too, which CAN show progress. The author states:

ASIWebPageRequests do not currently support progress tracking for an entire request with its external resources. However, progress updates from external resource requests are passed on to your delegate, so with a bit of work it may be possible to implement this yourself.