Reputation: 9867
In questions like How to draw a smooth circle..., ...Draw Circle... and ...draw filled Circles the question and answer is very broad, contains lots of unnecessary steps and the methods used isn't always the easiest to re-create or manage.
What is an easy way to draw a circle and add it to my UIView
?
Upvotes: 36
Views: 50967
Reputation: 31
Using CAShapeLayer Class makes drawing easy... 1.Create CAShapeLayer Object 2.Create a Circular path 3.Set the path to the wanted CAShapeLayer path 4.Add the layer to your view
let shapeLayer = CAShapeLayer()
let center = view.center
let circulPath = UIBezierPath(arcCenter: center, radius: 100, startAngle: 0, endAngle: 2.0 * CGFloat.pi, clockwise: true)
shapeLayer.path = circulPath.cgPath
view.layer.addSublayer(shapeLayer)
Note That ,here I draw the circle from center of the view. You can also set the fill color for your circle like bellow:
shapeLayer.fillColor = UIColor.red.cgColor
for further study you can check on CALayer.com
Upvotes: 0
Reputation: 9867
An easy way to draw a circle is to create a CAShapeLayer
and add a UIBezierPath
.
CAShapeLayer *circleLayer = [CAShapeLayer layer];
[circleLayer setPath:[[UIBezierPath bezierPathWithOvalInRect:CGRectMake(50, 50, 100, 100)] CGPath]];
let circleLayer = CAShapeLayer();
circleLayer.path = UIBezierPath(ovalIn: CGRect(x: 50, y: 50, width: 100, height: 100)).cgPath;
After creating the CAShapeLayer
we set its path
to be a UIBezierPath
.
Our UIBezierPath
then draws a bezierPathWithOvalInRect
. The CGRect
we set will effect its size and position.
Now that we have our circle, we can add it to our UIView
as a sublayer
.
[[self.view layer] addSublayer:circleLayer];
view.layer.addSublayer(circleLayer)
Our circle is now visible in our UIView
.
If we wish to customise our circle's color properties we can easily do so by setting the CAShapeLayer
's stroke
- and fill
color.
[circleLayer setStrokeColor:[[UIColor redColor] CGColor]];
[circleLayer setFillColor:[[UIColor clearColor] CGColor]];
shapeLayer.strokeColor = UIColor.red.cgColor;
shapeLayer.fillColor = UIColor.clear.cgColor;
Additionall properties can be found over at 's documentation on the subject https://developer.apple.com/.../CAShapeLayer_class/index.html.
Upvotes: 132