didAddSubview not working in ViewController
 If I create project using a View-based application template in Xcode using the iPhone SDK version 4.2 and add just this Objective-C code to the ViewController.m, right after |  #pragma mark - View lifecycle |  it does not trigger the log message in didAddSubview --  
- (void) loadView {
  [super loadView]:
  CGRect frame = CGRectMake(10.0, 10.0, 160, 230);
  UIView *newView = [[[UIView alloc] initWithFrame:frame] autorelease];
  [self.view addSubview:newView];
}
-(void) didAddSubview:(UIView *) subview {
  NSLog(@"subview added %@", subview);
}
Why this doesn't trigger the event handler when run?
 -didAddSubview:是UIView上的一个方法,而不是UIViewController 。 
