Can't show MBProgressHUD

Question

In here said that using MBProgressHUD is easy. But I can't make it.

Here my code:

- (IBAction)save{
    HUD = [[MBProgressHUD alloc] initWithView:self.navigationController.view];
    [self.navigationController.view addSubview:HUD];
    HUD.delegate = self;
    [HUD show:YES];

    NSString *title = [page stringByEvaluatingJavaScriptFromString:@"document.title"];
    SavePageAs *savePage = [[SavePageAs alloc] initWithUrl:self.site directory:title];
    [savePage save];
    [HUD hide:YES];
}

The progress indicator is not showing during savePage save method run, but shows after the page completely saved (the indicator is shown for less than 1 second).

I also tried this way:

- (IBAction)save {

    HUD = [[MBProgressHUD alloc] initWithView:self.navigationController.view];
   [self.navigationController.view addSubview:HUD];

   HUD.delegate = self;
   HUD.labelText = @"Saving...";

   [HUD showWhileExecuting:@selector(performFetchOnMainThread) onTarget:self withObject:nil animated:YES];
}

- (void) savingPage{
    NSString *title = [page stringByEvaluatingJavaScriptFromString:@"document.title"];
    SavePageAs *savePage = [[SavePageAs alloc] initWithUrl:self.site directory:title];
    [savePage save];
}

-(void) performFetchOnMainThread    {
    [self performSelectorOnMainThread:@selector(savingPage) withObject:nil waitUntilDone:YES];
}

But still no luck. Anyone let me know where I'm lack here?

P.S: savePage save is saving all website contents to local directory. I wish once the saving is complete the progressHUD disappear.

Thanks

Answer 1

Try allocation of HUD on the viewWillAppear: instead of -(IBAction)save because sometimes allocation takes up the whole time and by the time it allocates whole task is finished.

Copy Following links to viewWillAppear: and remove them from -(IBAction)save

 HUD = [[MBProgressHUD alloc] initWithView:self.navigationController.view];
 [self.navigationController.view addSubview:HUD];

 HUD.delegate = self;
 HUD.labelText = @"Saving...";

EDIT: Keep allocations on viewWillAppear: and change code as shown below:

- (IBAction)save {
    [NSThread detachNewThreadSelector:@selector(showHUD) withObject:nil];
    [self performSelectorOnMainThread:@selector(savingPage) withObject:nil waitUntilDone:YES];
}

- (void) savingPage{
    NSString *title = [page stringByEvaluatingJavaScriptFromString:@"document.title"];
    SavePageAs *savePage = [[SavePageAs alloc] initWithUrl:self.site directory:title];
    [savePage save];
    [HUD hide:YES];
}

-(void)showHUD {
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
   [HUD show:YES];
   [pool release];
}

What this will do is create a separate thread to display HUD as main thread is being engaged by savingPage method.

If this too doesn't work, then just change waitUntilDone:YES to waitUntilDone:NO

Note: As per Apple documentation

Important If you use Automatic Reference Counting (ARC), you cannot use autorelease pools directly. Instead, you use @autoreleasepool blocks instead. For example, in place of:

NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init;
// Code benefitting from a local autorelease pool.
[pool release];

you would write:

@autoreleasepool {
    // Code benefitting from a local autorelease pool.
}

@autoreleasepool blocks are more efficient than using an instance of NSAutoreleasePool directly; you can also use them even if you do not use ARC.

Hope this helps.