how to draw text in center to uiimage? - ios

Question

I want to set my text Sold Out to the center in UIimage. but it not in center .
func textToImage(drawText text: NSString, inImage image: UIImage, atPoint point: CGPoint) -> UIImage {
let textColor = UIColor.white
let textFont = UIFont(name: "Helvetica Bold", size: 32)!
let scale = UIScreen.main.scale
UIGraphicsBeginImageContextWithOptions(image.size, false, scale)
let textFontAttributes = [
NSFontAttributeName: textFont,
NSForegroundColorAttributeName: textColor,
] as [String : Any]
image.draw(in: CGRect(origin: CGPoint.zero, size: image.size))
// let rect = CGRect(origin: point , size: image.size)
let rect = CGRect(origin: CGPoint(x:(image.size.width/2), y: (image.size.height/2)), size: image.size)
text.draw(in: rect, withAttributes: textFontAttributes)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage!
}
caller function
imageViewSoldStatus.image = textToImage(drawText: "Sold out", inImage: UIImage(named:"soldout.png")!, atPoint: CGPoint(x: 5.0, y: 5.0))
I have spent of very long time to solve this problem but I could not find any solution.
Red flag my image
above is the screen I obtained. below is the design that I want to achieve.
update
Marie Dm answerd used! it is text align center but not image center
enter image description here

Answer 1

Try this:
func textToImage(drawText text: NSString, inImage image: UIImage) -> UIImage? {
//draw image first
UIGraphicsBeginImageContext(image.size)
image.draw(in: CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height))
//text attributes
let font=UIFont(name: "Helvetica-Bold", size: 32)!
let text_style=NSMutableParagraphStyle()
text_style.alignment=NSTextAlignment.center
let text_color=UIColor.white
let attributes=[NSFontAttributeName:font, NSParagraphStyleAttributeName:text_style, NSForegroundColorAttributeName:text_color]
//vertically center (depending on font)
let text_h=font.lineHeight
let text_y=(image.size.height-text_h)/2
let text_rect=CGRect(x: 0, y: text_y, width: image.size.width, height: text_h)
text.draw(in: text_rect.integral, withAttributes: attributes)
let result=UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return result
}

Answer 2

updated for Swift 5
func textToImage(drawText text: NSString, inImage image: UIImage) -> UIImage {
UIGraphicsBeginImageContext(image.size)
image.draw(in: CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height))
let font=UIFont(name: "Helvetica-Bold", size: 14)!
let text_style=NSMutableParagraphStyle()
text_style.alignment=NSTextAlignment.center
let text_color=UIColor.white
let attributes=[NSAttributedString.Key.font:font, NSAttributedString.Key.paragraphStyle:text_style, NSAttributedString.Key.foregroundColor:text_color]
let text_h=font.lineHeight
let text_y=(image.size.height-text_h)/2
let text_rect=CGRect(x: 0, y: text_y, width: image.size.width, height: text_h)
text.draw(in: text_rect.integral, withAttributes: attributes)
let result=UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return result!
}

Answer 3

Marie's answer updated for swift 4
func textToImage(drawText text: NSString, inImage image: UIImage) -> UIImage {
UIGraphicsBeginImageContext(image.size)
image.draw(in: CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height))
let font=UIFont(name: "Helvetica-Bold", size: 14)!
let text_style=NSMutableParagraphStyle()
text_style.alignment=NSTextAlignment.center
let text_color=UIColor.white
let attributes=[NSAttributedStringKey.font:font, NSAttributedStringKey.paragraphStyle:text_style, NSAttributedStringKey.foregroundColor:text_color]
let text_h=font.lineHeight
let text_y=(image.size.height-text_h)/2
let text_rect=CGRect(x: 0, y: text_y, width: image.size.width, height: text_h)
text.draw(in: text_rect.integral, withAttributes: attributes)
let result=UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return result!
}