Thread 1:EXC_BAD_ACCESS(code=2, address=0xbf7ffffc) - xcode4

Question

Am writing a simple multi view application with one root controller and two view controllers (blue and yellow). When I try to run it in the iPhone Simulator, I get an error by the #synthesize property. I have commented out the error on that line.
Can you tell me what the error means, and how can I get the app to run?
Thank you.
#import "SwitchViewController.h"
#import "BlueViewController.h"
#import "YellowViewController.h"
#interface SwitchViewController ()
#end
#implementation SwitchViewController
#synthesize yellowViewController;
#synthesize blueViewController; //Thread 1:EXC_BAD_ACCESS(code=2, address=0xbf7ffffc)
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)loadView
{
// If you create your views manually, you MUST override this method and use it to create your views.
// If you use Interface Builder to create your views, then you must NOT override this method.
}
- (void)viewDidLoad
{
self.blueViewController = [[BlueViewController alloc]initWithNibName:#"BlueView" bundle:nil];
[self.view insertSubview:self.blueViewController.view atIndex:0];
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
- (IBAction)switchViews:(id)sender
{
if(self.yellowViewController.view.superview==nil) {
if(self.yellowViewController==nil) {
self.yellowViewController =
[[YellowViewController alloc] initWithNibName:#"YellowView" bundle:nil];
}
[blueViewController.view removeFromSuperview];
[self.view insertSubview:self.yellowViewController.view atIndex:0];
} else {
if (self.blueViewController == nil) {
self.blueViewController =
[[BlueViewController alloc] initWithNibName:#"BlueView" bundle:nil];
}
}
}
- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview
[super didReceiveMemoryWarning];
// Release any cached data, images, etc. that aren't in use
if (self.blueViewController.view.superview == nil) {
self.blueViewController = nil;
} else {
self.yellowViewController = nil;
}
}
#end

Answer 1

Comment out the loadView method in your SwitchViewController, BlueViewController, and YellowViewController. The empty application template was changed to leave these uncommented in recent versions of XCode, but the Beginning iOS Development book you are following used an older version with the stubbed methods pre-commented.