loadingHud.swift

// Set up the shape of the circle 
CAShapeLayer *border = [CAShapeLayer layer];
border.path = [UIBezierPath bezierPathWithRoundedRect:self.myImageView.frame cornerRadius:self.myImageView.frame.size.height/2].CGPath; 
border.anchorPoint = CGPointMake(0.5, 0.5); 
border.position= CGPointMake(self.myImageView.bounds.origin.x, self.myImageView.bounds.origin.y); 
border.fillColor = [UIColor clearColor].CGColor; 
border.strokeColor = [UIColor blueColor].CGColor; 
border.lineWidth = 5; [self.view.layer addSublayer:border]; 
// Configure animation 
// draw Border 
CABasicAnimation *drawAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"]; 
drawAnimation.delegate = self; 
drawAnimation.duration = 7.0; 
drawAnimation.repeatCount = 1.0; 
[drawAnimation setValue:border forKey:@"afterBorderLoading"]; 
drawAnimation.fromValue = [NSNumber numberWithFloat:0.0f]; 
drawAnimation.toValue = [NSNumber numberWithFloat:1.0f]; 
drawAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseOut]; 
[border addAnimation:drawAnimation forKey:@"drawCircleAnimation"];