- (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. CALayer *layer = [CALayer layer]; layer.backgroundColor = [UIColor redColor].CGColor; //圓環底色 layer.frame = CGRectMake(100, 100, 110, 110); //創建一個圓環 UIBezierPath *bezierPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(55, 55) radius:50 startAngle:0 endAngle:M_PI*2 clockwise:YES]; //圓環遮罩 CAShapeLayer *shapeLayer = [CAShapeLayer layer]; shapeLayer.fillColor = [UIColor clearColor].CGColor; shapeLayer.strokeColor = [UIColor redColor].CGColor; shapeLayer.lineWidth = 5; shapeLayer.strokeStart = 0; shapeLayer.strokeEnd = 0.8; shapeLayer.lineCap = @"round"; shapeLayer.lineDashPhase = 0.8; shapeLayer.path = bezierPath.CGPath; //顏色漸變 NSMutableArray *colors = [NSMutableArray arrayWithObjects:(id)[UIColor redColor].CGColor,(id)[UIColor whiteColor].CGColor, nil]; CAGradientLayer *gradientLayer = [CAGradientLayer layer]; gradientLayer.shadowPath = bezierPath.CGPath; gradientLayer.frame = CGRectMake(50, 50, 60, 60); gradientLayer.startPoint = CGPointMake(0, 1); gradientLayer.endPoint = CGPointMake(1, 0); [gradientLayer setColors:[NSArray arrayWithArray:colors]]; [layer addSublayer:gradientLayer]; //設置顏色漸變 [layer setMask:shapeLayer]; //設置圓環遮罩 [self.view.layer addSublayer:layer]; //動畫 CABasicAnimation *scaleAnimation1 = [CABasicAnimation animationWithKeyPath:@"transform.scale"]; scaleAnimation1.fromValue = [NSNumber numberWithFloat:1.0]; scaleAnimation1.toValue = [NSNumber numberWithFloat:1.5]; scaleAnimation1.autoreverses = YES;// scaleAnimation1.fillMode = kCAFillModeForwards; scaleAnimation1.duration = 0.8; CABasicAnimation *rotationAnimation2 = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"]; rotationAnimation2.fromValue = [NSNumber numberWithFloat:0]; rotationAnimation2.toValue = [NSNumber numberWithFloat:6.0*M_PI]; rotationAnimation2.autoreverses = YES;// scaleAnimation.fillMode = kCAFillModeForwards; rotationAnimation2.repeatCount = MAXFLOAT; rotationAnimation2.beginTime = 0.8; //延時執行，注釋掉動畫會同時進行 rotationAnimation2.duration = 2; //組合動畫 CAAnimationGroup *groupAnnimation = [CAAnimationGroup animation]; groupAnnimation.duration = 4; groupAnnimation.autoreverses = YES; groupAnnimation.animations = @[scaleAnimation1, rotationAnimation2]; groupAnnimation.repeatCount = MAXFLOAT; [layer addAnimation:groupAnnimation forKey:@"groupAnnimation"];}- (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated.}@end