title: Passing Objects using Segue
body: <p>I have trouble understanding segues and how they work and pass objects. Basically I have a calculator and am trying to graph the objects stored in an array. So far I have an object called brain which is an instance of CalculatorBrain. Now brain has an NSArray property that I use as a stack to store variables. Let's say I add the values 3 and 5 to the array and then want to segue. I have my segue selected to a button called "Graph" so when I click the button it segues. How would I pass brain to the new view controller that I am segueing to? I have a property called setGraphingPoint which is defined in the new view controller which I think should accept the passed object. Also, if I pass brain through a segue will the values 3 and 5 be passed along with it or will it create a new object of CalculatorBrain? Here is what I have so far.</p>
  
  <p>This is defined in the new view controller</p>
  
  <pre><code>@property (nonatomic, strong) CalculatorBrain *graphingPoint;
  @synthesize graphingPoint = _graphingPoint;
  
  -(void) setGraphingPoint:(CalculatorBrain*) graphingPoint{
  
  _graphingPoint = graphingPoint;
  [self.graphingView setNeedsDisplay];
  
  }
  </code></pre>
  
  <p>This is called from the old view controller which will have button to segue</p>
  
  <pre><code>-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender{
  
  if([segue.identifier isEqualToString:@"Graph"])
      [segue.destinationViewController setGraphingPoint:[self.brain program]];
  </code></pre>