對象與對象之間的關係
繼承 複合
什麼是複合:
1個類是由其他幾個類組合而成的,他們之間的關係就叫複合。
複合與繼承之間的區別:
1.滿足繼承的關係:is a
當A類是一個B類,A類可以從B類繼承
2.滿足複合的關係:has a
A類有一個B類,A和B就複合關係
依賴
依賴:
1個對象的方法的參數是另一個對象,那麼他們的關係就是依賴關係。
main.m文件:
Person *per = [Person new];
Phone *iPhone=[Phone new];
[per callWithPhone:iPhone];
Person1 *per1=[Person1 new];
Book *book=[Book new];
per1.name=@"小明";
book.name=@"<三國演義>";
[per1 read:book];
[book showMasterName:per1];
NSLog(@"%@",book);
各個類文件:
#import <Foundation/Foundation.h>
#import "Book.h"
@interface Person1 : NSObject
@property(nonatomic,strong)NSString *name;
@property(nonatomic,strong)Book *book;
-(void)read:(Book *)book;
@end
#import "Person1.h"
@implementation Person1
-(void)read:(Book *)book{
NSLog(@"我在讀書%@",book.name);
}
@end
#import <Foundation/Foundation.h>
@class Person1;
@interface Book : NSObject
@property(nonatomic,strong) NSString *name;//書名
@property(nonatomic,strong) NSString *authorName;//作者名
-(void)showMasterName:(Person1 *)person;
@end
#import "Book.h"
#import "Person1.h"
@implementation Book
-(void)showMasterName:(Person1 *)person{
NSLog(@"我的主人是%@",person.name);
}
-(NSString *)description{
return@"我是一本書";
}
@end
#import <Foundation/Foundation.h>
#import "Phone.h"
@interface Person : NSObject
@property(nonatomic ,strong) NSString *name;
@property(nonatomic ,strong) Phone *phone;//價格
-(void)callWithPhone:(Phone *)phone;
@end
#import "Person.h"
@implementation Person
-(void)callWithPhone:(Phone *)phone
{
[phone callWithNumber:@"100"];
}
@end
#import <Foundation/Foundation.h>
@interface Phone : NSObject
@property(nonatomic ,strong) NSString *name;
@property(nonatomic ,assign) NSInteger price;//價格
-(void)callWithNumber:(NSString *)number;
@end
#import "Phone.h"
@implementation Phone
-(void)callWithNumber:(NSString *)number{
NSLog(@"正在呼叫%@",number);
}
@end
#import <Cocoa/Cocoa.h>
#import "CPU.h"
#import "Memory.h"
#import "MainBoard.h"
@interface Computer : NSObject
@property(nonatomic ,strong)CPU *cpu;
@property(nonatomic ,strong)MainBoard *mb;
@property(nonatomic ,strong)Memory *men;
-(void)playGame;
@end
#import "Computer.h"
@implementation Computer
@end
#import <Foundation/Foundation.h>
@interface Memory : NSObject
@property(nonatomic ,strong) NSString *brand;//品牌
@property(nonatomic ,strong) NSString *model;//型號
@end
#import "Memory.h"
@implementation Memory
@end
#import <Foundation/Foundation.h>
@interface MainBoard : NSObject
@property(nonatomic ,strong) NSString *brand;//品牌
@property(nonatomic ,strong) NSString *model;//型號
@end
#import "MainBoard.h"
@implementation MainBoard
@end
#import <Foundation/Foundation.h>
@interface CPU : NSObject
@property(nonatomic ,strong) NSString *brand;//品牌
@property(nonatomic ,strong) NSString *model;//型號
-(void)jisuan;
@end
#import "CPU.h"
@implementation CPU
-(void)jisuan
{
NSLog(@"我在計算...");
}
@end
當兩個類互相包含,就會出現循環引用問題,導致出錯
#import和@class的區別
#import:是講指定的文件全部拷貝
@class:不會拷貝任何內容 ,只是告訴編譯器存在這麼一個類可以使用
如何解決:
其中一個類不要使用#import來引入頭文件,而是使用@class來標註這是一個咧,並在.m文件重新引入頭文件。