iOS4 Programming Cookbook源代码

// // Tray.h // Objects // // Created by Vandad Nahavandipoor on 10-06-05. // Copyright 2010 All rights reserved. // #import <Foundation/Foundation.h> @class Tray; @protocol TrayProtocol <NSObject> @required - (void) trayHasRunoutofPaper:(Tray *)paramSender; @end @interface Tray : NSObject { @public id<TrayProtocol> ownerDevice; @private NSUInteger paperCount; } @property (nonatomic, assign) id<TrayProtocol> ownerDevice; @property (nonatomic, assign) NSUInteger paperCount; - (BOOL) givePapertoPrinter; /* Designated Initializer */ - (id) initWithOwnerDevice:(id<TrayProtocol>)paramOwnerDevice; @end