查看iOS屏幕帧数MGFPSStatus

在状态栏显示FPS状态，FPS是一秒钟渲染多少帧 Frame Per Second = FPS，FPS值为55~60最佳，低于这个范围就较为卡顿了。

使用方法

#if defined(DEBUG) || defined(_DEBUG)
  // 添加FPSStatus
  [[MGFPSStatus shareInstance] show];
#endif

状态栏MGFPSStatus

FPSStatus.m

@implementation MGFPSStatus {
    // 顶部FPSLabel
    UILabel *_fpsLabel;
    
    CADisplayLink *_displayLink;
    NSTimeInterval _lastTime;
    NSUInteger _count;
    
    UIColor *_fpsColor;
}

+ (instancetype)shareInstance
{
    static MGFPSStatus *_instance;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        
        _instance = [[MGFPSStatus alloc] init];
    });
    return _instance;
}

- (instancetype)init
{
    self = [super init];
    if (self) {
        
        // 创建label
        _fpsLabel = [[UILabel alloc] initWithFrame:CGRectMake(([UIScreen mainScreen].bounds.size.width)/2+30, 0, 50, 20)];
        
//        _fpsLabel.text = @"23344";
        _fpsLabel.font = [UIFont systemFontOfSize:12];
        _fpsLabel.layer.cornerRadius = 5;
        _fpsLabel.clipsToBounds = YES;
        _fpsLabel.textAlignment = NSTextAlignmentCenter;
        _fpsLabel.userInteractionEnabled = NO;
        _fpsLabel.backgroundColor = [UIColor colorWithWhite:1.000 alpha:0.700];
        
        // 创建定时器
        _displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(tick:)];
        [_displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
    }
    return self;
}

- (void)tick:(CADisplayLink *)link {
    // 第一次
    if (_lastTime == 0) {
        _lastTime = link.timestamp;
        return;
    }
    
    _count++;
    NSTimeInterval delta = link.timestamp - _lastTime;
    
    if (delta < 1) return;
    _lastTime = link.timestamp;
    float fps = _count / delta;
    _count = 0;
    
    NSMutableAttributedString *text = [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:@"%d FPS",(int)round(fps)]];
    
    // 根据卡顿程度显示颜色
    if (fps >= 55.0) {
        _fpsColor = [UIColor greenColor];
    } else if (fps>=50 && fps<55) {
        _fpsColor = [UIColor yellowColor];
    } else {
        _fpsColor = [UIColor redColor];
    }
    
    [text addAttribute:NSForegroundColorAttributeName value:_fpsColor range:NSMakeRange(0, text.length - 3)];
    [text addAttribute:NSForegroundColorAttributeName value:[UIColor blackColor] range:NSMakeRange(text.length - 3, 3)];
    _fpsLabel.attributedText = text;
}
- (void)dealloc
{
    [_displayLink invalidate];
    NSLog(@"release");
}

- (void)show {
    [[UIApplication sharedApplication].keyWindow addSubview:_fpsLabel];
}
@end

参考资料

iOS查看屏幕帧数工具--YYFPSLabel
iOS 性能调优,成为一名合格iOS程序员必须掌握的技能
JPFPSStatus
YYKit笔记之FPS