内存管理问题 --- NSTimer、CADisplayLink 循环引用问题

NSTimer

你如果用带Block 你可以用weak 来解决 那么下面着这种你是用weak解决不了的

- (void)viewDidLoad {
    [super viewDidLoad];

    NSTimer * timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(timerClick) userInfo:nil repeats:YES];
    self.timerC = timer;
}


- (void)timerClick {
    
    NSLog(@"%@",[NSThread currentThread]);
}

- (void)dealloc
{
    [self.timerC invalidate];
}

 

当你退出控制器定时器不会被释放如何解决？

直接解释 搞一个中间类 ,直接代码

#import <Foundation/Foundation.h>

@interface LSGProxy : NSObject
@property (nonatomic,weak) id target;//这个weak 是关键
+(instancetype)createWithtarget:(id)target;
@end

#import "LSGProxy.h"

@implementation LSGProxy
+(instancetype)createWithtarget:(id)target{
    LSGProxy *lp = [[LSGProxy alloc]init];
    lp.target = target;
    return lp;
}

- (id)forwardingTargetForSelector:(SEL)aSelector
{
    return self.target;
}
@end

 这里讲这个中间类 import 到这个VC

 NSTimer * timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:[LSGProxy createWithtarget:self] selector:@selector(timerClick) userInfo:nil repeats:YES];

 这样完美解决。

CADisplayLink

同理

    CADisplayLink * link = [CADisplayLink displayLinkWithTarget:[LSGProxy createWithtarget:self] selector:@selector(cadisplayLinkClcik)];
    [link addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
    self.linkC = link;

 这个中间类还可以用这个类做消息转发 NSProxy , 与 有什么区别呢？ NSObject  他们是同一个级别的，只是NSProxy是专门做消息转发的性能比NSObject高，也就是专业点吧下面代码展示：

@interface NSObject <NSObject> {
     Class isa;
 }

@interface NSProxy <NSObject> {
    Class    isa;
}

NSProxy

@interface Proxy : NSProxy
@property (nonatomic,weak) id target;
+(instancetype)createWithtarget:(id)target;
@end


#import "Proxy.h"

@implementation Proxy
+ (instancetype)createWithtarget:(id)target {
    Proxy * pr = [self alloc];
    pr.target = target;
    return pr;
}

- (NSMethodSignature *)methodSignatureForSelector:(SEL)sel {
    return [self.target methodSignatureForSelector:sel];
}

- (void)forwardInvocation:(NSInvocation *)invocation {
    [invocation invokeWithTarget:self.target];
}

 效果同样