当两个对象相互保留时,如何绕过交叉保留情况?
考虑这个类结构:
容器.h
@interface Container : NSObject {
NSObject *child;
}
@property (nonatomic, retain) NSObject *child;
@end
容器.m
@implementation Container
@synthesize child;
- (void)dealloc {
[child release];
[super dealloc];
}
@end
然后在测试内存保留计数时:
- (void)testDoubleRetain {
Container *A = [[Container alloc] init];
Container *B = [[Container alloc] init];
NSLog(@"A retainCount: %d", [A retainCount]);//returns 1
NSLog(@"B retainCount: %d", [B retainCount]);//returns 1
[A setChild:B];
[B setChild:A];
NSLog(@"A retainCount: %d", [A retainCount]);//returns 2
NSLog(@"B retainCount: %d", [B retainCount]);//returns 2
[A release];
[B release];
NSLog(@"A retainCount: %d", [A retainCount]);//returns 1
NSLog(@"B retainCount: %d", [B retainCount]);//returns 1
}
因此,据我了解,保留计数应该显示正确的计数。但是我最终如何真正解除分配对象,因为在这段代码之后,这两个对象将留在内存中。