Loading the content of a UIWebView before displaying it

Question

I have a set number of ViewControllers in my app. They are allocated and initialized at application launch and released at exit. They are used by a NavigationController to be pushed/popped. In these ViewControllers there are WebViews (actually there is nothing else).

My problem is : When I want to change de content (URL) of a WebView that is not on the current TopViewController, the content isn't loaded until I push/pop the associated ViewController.

And the transition us "ugly". The pushed/popped Viewcontroller shows old content at worst or blank page at best, before the ViewController is in full view THEN the new content is shown.

I tried lots of things (even putting the "loadRequest" in a different thread with looks stupid).

Do you know any way to make things go smooth?

Answer 1

In general you should plan your UI for slow UIWebView loads, because you can't plan ahead to know how long things will take. What I often do is have a UIView that has a spinner and a message such as "Loading..." that is layered on top of the UIWebView. Here's how I use it:

In viewWillAppear: I unhide the loading view and start the spinner.

In webViewDidFinishLoad I hide the loading view.

If webViewDidFail gets called, then you're not showing some interim or invalid content while the page loads. You can present a UIAlertView in that case.

If you're curious, you can see this in the high score page of my game (Lexitect, free)