Question

I have an UIActivityIndicator that should loop until a PDF file is loading.

I can’t understand why, but the indicator disappears before the PDF is loaded.
I can’t understand if the PDF file is too large (1,4 MB), if my app freezes, or if I wrote something wrong in the code

-(void)startTheProcess {

    act = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    //coordinate act
    [act setCenter:CGPointMake(320 / 2, 440 / 2)];
    self.act.hidden = FALSE;
    [self.view addSubview:act];
    [act startAnimating];
    [UIApplication sharedApplication].networkActivityIndicatorVisible = TRUE;
    [NSThread detachNewThreadSelector:@selector(creaVista) toTarget:self withObject:nil];
}

- (void) creaVista{

    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
    NSURL *url = [NSURL URLWithString:@"http://www.something.com/file.pdf"];
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    [pdfView loadRequest:request];
    [pdfView setScalesPageToFit:YES];
    [self performSelectorOnMainThread:@selector(processDone) withObject:nil waitUntilDone:NO];
    [pool release];
}
-(void)processDone {

    [act stopAnimating];
    [UIApplication sharedApplication].networkActivityIndicatorVisible = FALSE;
}

If I debug it, I can easily see that the debugger goes quickly to [act stopAnimating] and then stops, but the file is not yet loaded: after a few seconds the PDF appears.

Have you got any hints? I’m a noob and I think I’m doing some foolish mistakes…
Thanks

Answer 1

It sounds like Joshua has the right idea in the comments. The load is asynchronous and will return before the load is actually done.

If your pdfView is a UIWebView you can use the UIWebViewDelegate method webViewDidFinishLoad: to know when the PDF is done loading. If you place your [act stopAnimating] in there it should work.

You would also want to place it in webView:didFailLoadWithError: incase there are any errors.

To set the delegate on the pdfView do this: [pdfView setDelegate:self];
and make sure that you have your controller adopt the UIWebViewDelegate like this:
@interface ClassName : ItsSuperclass < UIWebViewDelegate >