[英]how to position a rotating CAShapeLayer at certain point in UIImageView?
我有以下代碼,使橢圓圍繞其中心旋轉。 我希望能夠將其定位在UIImageView
中的某個位置(例如視圖的中間)。
如果有人可以幫助我,我將非常感激。
-(void)drawCircle
{
CGMutablePathRef circlePath = CGPathCreateMutable();
int radius = 400;
CGRect circleRect = CGRectMake(CENTER_Y-radius*0.7, CENTER_X-radius, 1.4*radius, 2*radius);
float midX = CGRectGetMidX(circleRect);
float midY = CGRectGetMidY(circleRect);
CGAffineTransform transform = CGAffineTransformMakeTranslation(-midX, -midY);
CGPathAddEllipseInRect( circlePath ,&transform , circleRect);
CAShapeLayer *circle = [[CAShapeLayer alloc] init];
circle.path = circlePath;
circle.opacity = 0.1;
circle.contentsScale = SCREEN_SCALE;
circle.fillColor = [UIColor blueColor].CGColor;
[aView.layer addSublayer:circle];
CABasicAnimation* theAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
theAnimation.fromValue = 0;
theAnimation.toValue = @(2*M_PI);
theAnimation.duration=3.5;
theAnimation.autoreverses=FALSE;
theAnimation.repeatCount=HUGE_VALF;
theAnimation.fillMode = kCAFillModeBoth;
theAnimation.removedOnCompletion=FALSE;
theAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
[circle addAnimation:theAnimation forKey:@"transform.rotation.z"];
}
丟失的一塊:
[circle setPosition:CGPointMake(CENTER_X, CENTER_Y)];
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.