Example/Colors-OSX/ViewController.h
#import <Cocoa/Cocoa.h>
@interface ViewController : NSViewController
@property (weak) IBOutlet NSView *leftView;
@property (weak) IBOutlet NSView *rightView;
@property (weak) IBOutlet NSTextField *leftLabel;
@property (weak) IBOutlet NSTextField *rightLabel;
@property(nonatomic, strong) NSView *leftColoredView;
@property(nonatomic, strong) NSView *rightColoredView;
@end