title: XCode Linking build error
body: <p>This one is new to me. Not even sure what RootViewController.o is? though this project does have a <strong>.m</strong> &amp; <strong>.h</strong>. Building for Simulator 3.0. Cleaned before build (Shift-⌘-K). </p>
  
  <p>Recently added some classes from another project that also had a RootViewController...but I didn't transfer old one over. Haven't built since. This could be part of the problem?!?</p>
  
  <p><strong>Building target “MyApp” of project “MyApp” with configuration “Debug” — (1 error)</strong></p>
  
  <pre><code>    cd "/Volumes/MacHD/Development/iPhone/MyApp"
      setenv MACOSX_DEPLOYMENT_TARGET 10.5
      setenv PATH "/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
      /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.2 -arch i386 -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator3.0.sdk -L/Volumes/MacHD/Development/iPhone/MyApp/build/Debug-iphonesimulator -F/Volumes/MacHD/Development/iPhone/MyApp/build/Debug-iphonesimulator -filelist /Volumes/MacHD/Development/iPhone/MyApp/build/MyApp.build/Debug-iphonesimulator/MyApp.build/Objects-normal/i386/MyApp.LinkFileList -mmacosx-version-min=10.5 -framework Foundation -framework UIKit -framework CoreGraphics -framework AddressBook -framework AddressBookUI -o /Volumes/MacHD/Development/iPhone/MyApp/build/Debug-iphonesimulator/MyApp.app/MyApp
  Undefined symbols:
    ".objc_class_name_MyViewController", referenced from:
        literal-pointer@__OBJC@__cls_refs@MyViewController in RootViewController.o
  ld: symbol(s) not found
  collect2: ld returned 1 exit status
  </code></pre>
  
  <p>Build failed (1 error)</p>
  
  <hr>
  
  <p><strong>Edit:</strong> Cleaned ALL targets... still won't build. Here's my #includes:</p>
  
  <p><strong>RootViewController.h</strong>:</p>
  
  <pre><code>#import &lt;UIKit/UIKit.h&gt;
  #import "MyViewController.h" //tried with this and as @class MyViewController
  
  @class AddViewController, EditingViewController;
  
  @interface RootViewController : UITableViewController &lt;UITableViewDelegate, UITableViewDataSource&gt; {
      MyViewController *myVC;
      UINavigationController *navController;
      AddViewController *addViewController;
      NSArray *keys;
      NSNumberFormatter *currencyFormatter;
  }
  </code></pre>
  
  <p><strong>RootViewController.m:</strong></p>
  
  <pre><code>#import "RootViewController.h"
  #import "MyAppDelegate.h"
  #import "MyViewController.h"
  #import "AddViewController.h" 
  #import "EditingViewController.h"
  #import "MyObject.h"
  #import "ViewCell.h"
  #import "AppColors.h"
  #import "CustomCellBackgroundView.h"
  
  // Manage the editing view controller from this class so it can be easily accessed from both the detail and add controllers.
  static EditingViewController *__editingViewController = nil;
  
  @implementation RootViewController
  </code></pre>