摘要：
#import @interface model : NSObject@property(nonatomic,copy)NSString *bookName;@property(nonatomic,assign)double BookPrice;@end//实现委托@interface model(... 阅读全文
摘要：
发送通知[[NSNotificationCenter defaultCenter]postNotificationName:@"change" object:nil];注册通知[[NSNotificationCenter defaultCenter]addObserver:self selecto... 阅读全文