What works in viewDidUnload should be moved to didReceiveMemoryWarning?

In new iOS 6, viewDidUnload is deprecated and we have been instructed to use didReceiveMemoryWarning instead, to manage objects in UIViewController instances and subclasses. Is it equally effective to assign nils to UIView kinds inside didReceiveMemoryWarning like the way it has been done inside viewDidUnload?

I am asking this because these two methods seems to be working differently. It seems like didReceiveMemoryWarning doesn't guarantee viewDidLoad to be called again to re-instantiate any necessary UIViews.

I suspect with iOS 6, memory management is done without requiring to manually deallocate UIView. Please help me to know what I have missed in understanding the lifecycle of UIViewController.

My preferred method is now the following:

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    if (self.isViewLoaded && !self.view.window) {
        self.view = nil;
    }
    // Do additional cleanup if necessary
}

Note that the test self.isViewLoaded is essential, as otherwise accessing the view causes it to load - even the WWDC videos tend to miss that.

If your other references to subviews are weak references, you don't have to nil them out here, otherwise you want to set them to nil, too.

You should get rid of viewDidUnload completely, and every code there should move to appropriate places. It wasn't guaranteed to be called prior to iOS 6 before anyway.