How to create a UIImage with UIBezierPath

Question

I wrote some code to create a UIImage with UIBezierPath but it didn't work.

Can someone help me find out what's wrong with my code?

-(UIImage*) drawTriangle{
    CGRect rect = CGRectMake(0.0, 0.0, 30.0, 30.0);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    UIGraphicsPushContext(context);
    UIBezierPath *bezier = [UIBezierPath bezierPathWithRect:rect];
    [bezier moveToPoint:CGPointMake(25, 5)];
    [bezier addLineToPoint:CGPointMake(5, 15)];
    [bezier addLineToPoint:CGPointMake(25, 25)];
    [bezier setLineWidth:3.0];
    [bezier setLineJoinStyle:kCGLineJoinBevel];
    [bezier stroke];
    CGContextAddPath(context, bezier.CGPath);
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsPopContext();
    UIGraphicsEndImageContext();
    return image;
}

Answer 1

extension UIBezierPath {
    func shapeImage(view: UIView) -> UIImage! {
    
    // begin graphics context for drawing
    UIGraphicsBeginImageContextWithOptions(view.frame.size, false, UIScreen.main.scale)
    
    // configure the view to render in the graphics context
    //view.layer.render(in: UIGraphicsGetCurrentContext()!)
    
    // get reference to the graphics context
    let context = UIGraphicsGetCurrentContext()
    
    // translate matrix so that path will be centered in bounds
    context?.translateBy(x: -(bounds.origin.x - self.lineWidth), y: -(bounds.origin.y - self.lineWidth))
    // set color
    UIColor.black.setStroke()
    
    // draw the stroke
    stroke()
    
    // get an image of the graphics context
    let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
    
    // end the context
    UIGraphicsEndImageContext()
    
    return image
    }
}

Answer 2

https://stackoverflow.com/a/17408397/3191351 Translated Into Swift

import UIKit

extension UIBezierPath {

    /** Returns an image of the path drawn using a stroke */
    func strokeImageWithColor(var strokeColor: UIColor?,var fillColor: UIColor?) -> UIImage {

        // get your bounds
        let bounds: CGRect = self.bounds

        UIGraphicsBeginImageContextWithOptions(CGSizeMake(bounds.size.width + self.lineWidth * 2, bounds.size.width + self.lineWidth * 2), false, UIScreen.mainScreen().scale)

        // get reference to the graphics context
        let reference: CGContextRef = UIGraphicsGetCurrentContext()!

        // translate matrix so that path will be centered in bounds
        CGContextTranslateCTM(reference, self.lineWidth, self.lineWidth)

        if strokeColor == nil {
            strokeColor = fillColor!;
        }
        else if fillColor == nil {
            fillColor = strokeColor!;
        }

        // set the color
        fillColor?.setFill()
        strokeColor?.setStroke()

        // draw the path
        fill()
        stroke()


        // grab an image of the context
        let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()

        UIGraphicsEndImageContext()

        return image
    }

}