objective-C 复合(组合)

复合：将多个组件组合在一起，形成一个整体，然后使用整体来进行工作，这种组合行为称为复合

复合后的整体功能更加强大

编写一个房屋类，由门，窗户等组成，门和窗有自己的开关方法，然后将门和窗这些复合在一起称为房屋类
调用房屋类的进出方法实际调用到门的开关
调用房屋的换气方法，实际调用到窗户的开关

// 由多个类的对象组成一个大类，就是一个组合的过程
#import <Foundation/Foundation.h>
#import "Widow.h"
#import "Door.h"
@interface House : NSObject

@property (nonatomic, strong) Door *door;
@property (nonatomic, strong) Widow *widow;
-(void)inouthouse;
-(void)exchangair;
@end

#import "House.h"

@implementation House

-(void)inouthouse{
    [_door open ];NSLog(@"进屋");
    [_door close];  NSLog(@"出屋");
}
-(void)exchangair{
     [_widow open];
    NSLog(@"开始换气");
    [_widow close];
    NSLog(@"换气结束");
}
@end

#import <Foundation/Foundation.h>

@interface Widow : NSObject -(void)open; -(void)close; @end #import "Widow.h" 

@implementation Widow -(void)open{ NSLog(@"开窗"); } 

-(void)close{ NSLog(@"关窗"); } @end

#import <Foundation/Foundation.h>

@interface Door : NSObject
-(void)open;
-(void)close;
@end

#import "Door.h"

@implementation Door
-(void)open{
    NSLog(@"开门");
}
-(void)close{
    NSLog(@"关门");
}
@end

#import <Foundation/Foundation.h>
#import "House.h"
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        House *h=[[House alloc]init];
        h.door=[[Door alloc]init];
        h.widow=[[Widow alloc]init];

        [h inouthouse];
        [h exchangair];

    }
    return 0;
}