将Apple Emoji(String)转换为UIImage

Question

我需要所有Apple Emojis.
我可以通过从网站getemoji复制它们来获取所有表情符号并将它们放入字符串中,但在我的应用程序中,我需要以正确的顺序将表情符号作为图像. 有没有一种很好的方法将我复制的表情符号转换为字符串到UIImage？ 或者更好的解决方案,以正确的顺序获得所有Apple表情符号？

Answer 1

更新了Swift 4.1

将此扩展添加到您的项目中

import UIKit

extension String {
    func image() -> UIImage? {
        let size = CGSize(width: 40, height: 40)
        UIGraphicsBeginImageContextWithOptions(size, false, 0)
        UIColor.white.set()
        let rect = CGRect(origin: .zero, size: size)
        UIRectFill(CGRect(origin: .zero, size: size))
        (self as AnyObject).draw(in: rect, withAttributes: [.font: UIFont.systemFont(ofSize: 40)])
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image
    }
}

上面的代码将当前绘制为String具有白色背景颜色的图像上下文,最后将其转换为UIImage.

现在你可以写了

例

给出指示表情符号的unicode值的范围列表

let ranges = [0x1F601...0x1F64F, 0x2702...0x27B0]

您可以将其转换为图像列表

let images = ranges
    .flatMap { $0 }
    .compactMap { Unicode.Scalar($0) }
    .map(Character.init)
    .compactMap { String($0).image() }

结果:

我无法保证范围列表已完成,您需要自己搜索

Answer 2

这是更新后的答案，其中包含以下更改：

• 居中：用于draw(at:withAttributes:)代替draw(in:withAttributes:)在生成的 UIImage 中居中文本
• 正确大小：用于size(withAttributes:)生成大小与字体实际大小相关的结果 UIImage。
• 评论：添加评论以更好地理解

斯威夫特5

import UIKit
extension String {
    func textToImage() -> UIImage? {
        let nsString = (self as NSString)
        let font = UIFont.systemFont(ofSize: 1024) // you can change your font size here
        let stringAttributes = [NSAttributedString.Key.font: font]
        let imageSize = nsString.size(withAttributes: stringAttributes)

        UIGraphicsBeginImageContextWithOptions(imageSize, false, 0) //  begin image context
        UIColor.clear.set() // clear background
        UIRectFill(CGRect(origin: CGPoint(), size: imageSize)) // set rect size
        nsString.draw(at: CGPoint.zero, withAttributes: stringAttributes) // draw text within rect
        let image = UIGraphicsGetImageFromCurrentImageContext() // create image from context
        UIGraphicsEndImageContext() //  end image context

        return image ?? UIImage()
    }
}

斯威夫特3.2

import UIKit
extension String {
    func textToImage() -> UIImage? {
        let nsString = (self as NSString)
        let font = UIFont.systemFont(ofSize: 1024) // you can change your font size here
        let stringAttributes = [NSFontAttributeName: font]
        let imageSize = nsString.size(attributes: stringAttributes)

        UIGraphicsBeginImageContextWithOptions(imageSize, false, 0) //  begin image context
        UIColor.clear.set() // clear background
        UIRectFill(CGRect(origin: CGPoint(), size: imageSize)) // set rect size
        nsString.draw(at: CGPoint.zero, withAttributes: stringAttributes) // draw text within rect
        let image = UIGraphicsGetImageFromCurrentImageContext() // create image from context
        UIGraphicsEndImageContext() //  end image context

        return image ?? UIImage()
    }
}

Answer 3

Swift 4也是如此:

extension String {
    func emojiToImage() -> UIImage? {
        let size = CGSize(width: 30, height: 35)
        UIGraphicsBeginImageContextWithOptions(size, false, 0)
        UIColor.white.set()
        let rect = CGRect(origin: CGPoint(), size: size)
        UIRectFill(rect)
        (self as NSString).draw(in: rect, withAttributes: [NSAttributedStringKey.font: UIFont.systemFont(ofSize: 30)])
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image
    }
}

Answer 4

更新了@Luca Angeletti对Swift 3.0.1的回答

extension String {

    func image() -> UIImage? {
        let size = CGSize(width: 30, height: 35)
        UIGraphicsBeginImageContextWithOptions(size, false, 0);
        UIColor.white.set()
        let rect = CGRect(origin: CGPoint(), size: size)
        UIRectFill(CGRect(origin: CGPoint(), size: size))
        (self as NSString).draw(in: rect, withAttributes: [NSFontAttributeName: UIFont.systemFont(ofSize: 30)])
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image
    }

}

Answer 5

Swift 5：（带有可选的 fontSize、imageSize 和 bgColor）

像这样使用它：

let image      = "".image()
let imageLarge = "".image(fontSize:100)
let imageBlack = "".image(fontSize:100, bgColor:.black)
let imageLong  = "".image(fontSize:100, imageSize:CGSize(width:500,height:100))

import UIKit

extension String
{
    func image(fontSize:CGFloat = 40, bgColor:UIColor = UIColor.clear, imageSize:CGSize? = nil) -> UIImage?
    {
        let font = UIFont.systemFont(ofSize: fontSize)
        let attributes = [NSAttributedString.Key.font: font]
        let imageSize = imageSize ?? self.size(withAttributes: attributes)

        UIGraphicsBeginImageContextWithOptions(imageSize, false, 0)
        bgColor.set()
        let rect = CGRect(origin: .zero, size: imageSize)
        UIRectFill(rect)
        self.draw(in: rect, withAttributes: [.font: font])
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image
    }
}

Answer 6

Swift 4.2

我真的很喜欢@Luca Angeletti解决方案.关于透明背景我和@jonauz有同样的问题.因此,通过这个小修改,您可以得到相同的东西,但背景颜色清晰.

我没有让评论在评论中回答.

import UIKit

extension String {
    func emojiToImage() -> UIImage? {
        let size = CGSize(width: 30, height: 35)
        UIGraphicsBeginImageContextWithOptions(size, false, 0)
        UIColor.clear.set()
        let rect = CGRect(origin: CGPoint(), size: size)
        UIRectFill(CGRect(origin: CGPoint(), size: size))
        (self as NSString).draw(in: rect, withAttributes: [NSAttributedString.Key.font: UIFont.systemFont(ofSize: 30)])
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image
    }
}