在主线程里加入一个loading画面…

{
   [window addSubview:view_loading];
   [NSThread detachNewThreadSelector:@selector(init_backup:) toTarget:self withObject:nil];
}

- (void)init_backup:(id)sender
{
   NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

   //    ...
   int i = status;
   [self performSelectorOnMainThread:@selector(show_loading:) withObject:[NSNumber numberWithInt:i] waitUntilDone:NO];

   [view_loading removeFromSuperview];
   [window addSubview:tabcontroller_main.view];
   [pool release];
}