I am trying to develop my app in Xcode 5 and debug it under iOS 7 environment.
I have a customized UICollectionViewLayoutAttributes.
I plan to do something after
Yes. As Calman said you must override isEqual: method to compare custom properties that you have. See the apple documentation here
If you subclass and implement any custom layout attributes, you must also override the inherited isEqual: method to compare the values of your properties. In iOS 7 and later, the collection view does not apply layout attributes if those attributes have not changed. It determines whether the attributes have changed by comparing the old and new attribute objects using the isEqual: method. Because the default implementation of this method checks only the existing properties of this class, you must implement your own version of the method to compare any additional properties. If your custom properties are all equal, call super and return the resulting value at the end of your implementation.