更新时间:2022-06-27 02:10:00
main.m文件:
1
2
3
4
5
6
7
8
9
10
11
12
13
|
#import <Foundation/Foundation.h> #import "Person.h" #import "Dog.h" int main()
{ Person *p = [[Person alloc] init];
Dog *d = [[Dog alloc] init];
p.dog = d;
d.person = p;
return 0;
} |
1
2
3
4
5
6
7
8
|
#import "Dog.h" @implementation Dog - ( void )dealloc
{ NSLog(@ "Dog--dealloc" );
} @end |
1
2
3
4
5
6
7
8
9
10
|
#import "Person.h" @implementation Person - ( void )dealloc
{ NSLog(@ "Person--dealloc" );
} @end |
1
2
3
4
5
6
7
8
9
|
#import <Foundation/Foundation.h> @ class Person;
@interface Dog : NSObject @property (nonatomic,strong) Person *person; @end |
1
2
3
4
5
6
7
8
9
|
#import <Foundation/Foundation.h> @ class Dog;
@interface Person : NSObject @property (nonatomic, strong) Dog *dog; @end |
对于上述main.m文件中红色部分“人养一条狗,狗有一个主人”,仔根据两个.h文件中部分,编译运行时会出现“人strong狗,狗strong人”的情况,导致p和d占用的内存无法被回收,即上图黄色部分不打印。解决办法为:
一端用strong,另一端用weak
比如可以将Dog.h文件中strong改成weak,就可以解决循环strong 问题。