title: Message sent to deallocated instance using ARC
body: <p>I wouldn't normally ask questions like this, but I really cant get my head around it. I have a class 'GetTableInfoFromDatabase', which connects to my database and downloads some JSON. This works great from the first screen of my tab-bar application. I can call the getNewData method as much as I want to effectively refresh the data.</p>
  
  <p>My problem arises when I try and create an instance of the 'GetTableInfoFromDatabase' class and call the very same method from another tab. I get the following error:</p>
  
  <pre><code>*** -[GetTableInfoFromDatabase respondsToSelector:]: message sent to deallocated instance 0x1d89e830
  </code></pre>
  
  <p>The funny thing is, i'm using ARC. The culprit (in my opinion) is ASIHTTPRequest. I have had to enable -fno-objc-arc to get the project to compile. This library is used in the GetTableInfoFromDatabase class.</p>
  
  <p>Here is the class:</p>
  
  <pre><code>- (void) getEventDataWithSender:(id)sender{
  
  
  ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:[NSURL URLWithString:@"-------.com/getdata.php"]];
  [request setDelegate:self];
  NSLog(@"Running!");
  [request startAsynchronous];
  AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
  self.managedObjectContext = appDelegate.managedObjectContext;
  }
  </code></pre>
  
  <p>And this is how i'm calling it:</p>
  
  <pre><code>GetTableInfoFromDatabase *getInfo = [[GetTableInfoFromDatabase alloc]init];
  [getInfo getEventDataWithSender:self];
  </code></pre>
  
  <p>I've even changed the order of the tabs around, so the first tab to be displayed purely just calls this method, nothing else. Not even before the 'GetTableInfoFromDatabase' has been previously initialised by the class that initialised it first last time. Still crashes.</p>
  
  <p>Has anyone got any ideas? This is so frustrating!</p>