iOS 性能優化

1、弱應用

__weak typeof(self) weakSelf = self;
__strong typeof(self) strongSelf = weakSelf;

2、NSTimer

方法一：

#import <objc/runtime.h>

@property (nonatomic, strong) NSTimer *timer;
@property (nonatomic, strong) id target;

_target = [NSObject new];
class_addMethod([_target class], @selector(test), class_getMethodImplementation([self class], @selector(test)), "v@:");
_timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:_target selector:@selector(test) userInfo:nil repeats:YES];

- (void)test{
    NSLog(@"test");
}

-(void)dealloc{
    NSLog(@"dealloc");
    [_timer invalidate];
    _timer = nil;
}

方法二：

-(void)didMoveToParentViewController:(UIViewController *)parent
{
    if (!parent) {
        [_timer invalidate];
        _timer = nil;
    }
}

方法三：

#import <Foundation/Foundation.h>
NS_ASSUME_NONNULL_BEGIN
@interface TestProxy : NSProxy
@property (nonatomic, weak) id target;
@end
NS_ASSUME_NONNULL_END

#import "TestProxy.h"
@implementation TestProxy
-(NSMethodSignature *)methodSignatureForSelector:(SEL)sel{
    return [self.target methodSignatureForSelector:sel];
}
-(void)forwardInvocation:(NSInvocation *)invocation{
    [invocation invokeWithTarget:self.target];
}
@end

@property (nonatomic, strong) TestProxy *testProxy;
_testProxy = [TestProxy alloc]; 
_testProxy.target = self;
_timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:_testProxy selector:@selector(test) userInfo:nil repeats:YES];

方法四：

#import <Foundation/Foundation.h>
@interface NSTimer (JNTimer)
+ (NSTimer *)jn_scheduledTimerWithTimeInterval:(NSTimeInterval)interval repeats:(BOOL)repeats block:(void (^)(void))block;
@end

#import "NSTimer+JNTimer.h"
@implementation NSTimer (JNTimer)
+ (NSTimer *)jn_scheduledTimerWithTimeInterval:(NSTimeInterval)interval repeats:(BOOL)repeats block:(void (^)(void))block{
    return [self scheduledTimerWithTimeInterval:interval target:self selector:@selector(jn_blockHandle:) userInfo:block repeats:YES];
}
+ (void)jn_blockHandle:(NSTimer *)timer{
    void(^block)(void) = timer.userInfo;
    if (block) {
        block();
    }
}
@end

__weak typeof(self) weakSelf = self;
_timer = [NSTimer jn_scheduledTimerWithTimeInterval:1.0 repeats:YES block:^{
     __strong typeof(self) strongSelf = weakSelf;
     [strongSelf test];
}];

Demo：https://github.com/JnKindle/PerformanceOptimization-NSTimer

歡迎大家訪問我的GitHub

GitTub：https://github.com/JnKindle