Create circle in iOS Objective C with and without fill

Solution:

In iOS you can create a circle using CGContextref. The below code is used for draw a circle in a view with 0 x axis,0 y axis,width 20 and height 20..

    CGContextRef ctx = UIGraphicsGetCurrentContext();

    CGRect rect = CGRectMake(0, 0,20,20)

    CGContextClearRect(ctx, rect);

    CGContextSetLineWidth(ctx, 10);
     CGContextStrokeEllipseInRect(UIGraphicsGetCurrentContext(), rect);

If you want to fill the rectangle then add the below code 

        CGContextSetFillColorWithColor(ctx, color.CGColor);
        CGContextFillEllipseInRect(UIGraphicsGetCurrentContext(), rect);