As of OSX 10.7:
- (void)layout is equivalent to layoutSubviews
There is now an identical setNeedsLayout.
Override this method if your custom view needs to perform custom layout not expressible using the constraint-based layout system. In this case you are responsible for calling setNeedsLayout: when something that impacts your custom layout changes.
You may not invalidate any constraints as part of your layout phase, nor invalidate the layout of your superview or views outside of your view hierarchy. You also may not invoke a drawing pass as part of layout.
You must call [super layout] as part of your implementation.