斯威夫特5

重绘图像的背景和填充颜色

extension UIImage {
  func withBackground(color: UIColor, fill fillColor: UIColor) -> UIImage {
    UIGraphicsBeginImageContextWithOptions(size, true, scale)
    
    guard let ctx = UIGraphicsGetCurrentContext(), let image = cgImage else { return self }
    defer { UIGraphicsEndImageContext() }
    
    ctx.concatenate(CGAffineTransform(a: 1, b: 0, c: 0, d: -1, tx: 0, ty: size.height))
    
    let rect = CGRect(origin: .zero, size: size)
    
    // draw background
    ctx.setFillColor(color.cgColor)
    ctx.fill(rect)
    
    // draw image with fill color
    ctx.clip(to: rect, mask: image)
    ctx.setFillColor(fillColor.cgColor)
    ctx.fill(rect)
    
    return UIGraphicsGetImageFromCurrentImageContext() ?? self
  }
}

我必须在Swift中使用扩展来做到这一点。

我想分享一下我是如何做到的:

extension UIImage {
    func imageWithColor(color1: UIColor) -> UIImage {
        UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale)
        color1.setFill()

        let context = UIGraphicsGetCurrentContext() as CGContextRef
        CGContextTranslateCTM(context, 0, self.size.height)
        CGContextScaleCTM(context, 1.0, -1.0);
        CGContextSetBlendMode(context, CGBlendMode.Normal)

        let rect = CGRectMake(0, 0, self.size.width, self.size.height) as CGRect
        CGContextClipToMask(context, rect, self.CGImage)
        CGContextFillRect(context, rect)

        let newImage = UIGraphicsGetImageFromCurrentImageContext() as UIImage
        UIGraphicsEndImageContext()

        return newImage
    }
}

用法:

theImageView。image = theImageView.image.imageWithColor(uiccolor . redcolor ())

斯威夫特4

extension UIImage {
    func imageWithColor(color1: UIColor) -> UIImage {
        UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale)
        color1.setFill()

        let context = UIGraphicsGetCurrentContext()
        context?.translateBy(x: 0, y: self.size.height)
        context?.scaleBy(x: 1.0, y: -1.0)
        context?.setBlendMode(CGBlendMode.normal)

        let rect = CGRect(origin: .zero, size: CGSize(width: self.size.width, height: self.size.height))
        context?.clip(to: rect, mask: self.cgImage!)
        context?.fill(rect)

        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return newImage!
    }
}

用法:

theImageView。image = theImageView.image?imageWithColor (color1 UIColor.red):

斯威夫特5

重绘图像的背景和填充颜色

extension UIImage {
  func withBackground(color: UIColor, fill fillColor: UIColor) -> UIImage {
    UIGraphicsBeginImageContextWithOptions(size, true, scale)
    
    guard let ctx = UIGraphicsGetCurrentContext(), let image = cgImage else { return self }
    defer { UIGraphicsEndImageContext() }
    
    ctx.concatenate(CGAffineTransform(a: 1, b: 0, c: 0, d: -1, tx: 0, ty: size.height))
    
    let rect = CGRect(origin: .zero, size: size)
    
    // draw background
    ctx.setFillColor(color.cgColor)
    ctx.fill(rect)
    
    // draw image with fill color
    ctx.clip(to: rect, mask: image)
    ctx.setFillColor(fillColor.cgColor)
    ctx.fill(rect)
    
    return UIGraphicsGetImageFromCurrentImageContext() ?? self
  }
}

斯威夫特4

改变UIImage SVG / PDF的色调，适用于颜色独特的图像:

import Foundation
    
// MARK: - UIImage extensions

public extension UIImage {

    //
    /// Tint Image
    ///
    /// - Parameter fillColor: UIColor
    /// - Returns: Image with tint color
    func tint(with fillColor: UIColor) -> UIImage? {
        let image = withRenderingMode(.alwaysTemplate)
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        fillColor.set()
        image.draw(in: CGRect(origin: .zero, size: size))

        guard let imageColored = UIGraphicsGetImageFromCurrentImageContext() else {
            return nil
        }
        
        UIGraphicsEndImageContext()
        return imageColored
    }
}

改变UIImageView的色调，这适用于具有独特颜色的图像:

let imageView = UIImageView(frame: CGRect(x: 50, y: 50, width: 50, height: 50))
imageView.image = UIImage(named: "hello.png")!.withRenderingMode(.alwaysTemplate)
imageView.tintColor = .yellow

改变图片的UIImage的色调，使用它:

import Foundation

// MARK: - Extensions UIImage

public extension UIImage {

    /// Tint, Colorize image with given tint color
    /// This is similar to Photoshop's "Color" layer blend mode
    /// This is perfect for non-greyscale source images, and images that 
    /// have both highlights and shadows that should be preserved<br><br>
    /// white will stay white and black will stay black as the lightness of 
    /// the image is preserved
    ///
    /// - Parameter TintColor: Tint color
    /// - Returns:  Tinted image
    public func tintImage(with fillColor: UIColor) -> UIImage {
        
        return modifiedImage { context, rect in
            // draw black background - workaround to preserve color of partially transparent pixels
            context.setBlendMode(.normal)
            UIColor.black.setFill()
            context.fill(rect)
            
            // draw original image
            context.setBlendMode(.normal)
            context.draw(cgImage!, in: rect)
            
            // tint image (loosing alpha) - the luminosity of the original image is preserved
            context.setBlendMode(.color)
            fillColor.setFill()
            context.fill(rect)
            
            // mask by alpha values of original image
            context.setBlendMode(.destinationIn)
            context.draw(context.makeImage()!, in: rect)
        }
    }
    
    /// Modified Image Context, apply modification on image
    ///
    /// - Parameter draw: (CGContext, CGRect) -> ())
    /// - Returns:        UIImage
    fileprivate func modifiedImage(_ draw: (CGContext, CGRect) -> ()) -> UIImage {
        
        // using scale correctly preserves retina images
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        let context: CGContext! = UIGraphicsGetCurrentContext()
        assert(context != nil)
        
        // correctly rotate image
        context.translateBy(x: 0, y: size.height)
        context.scaleBy(x: 1.0, y: -1.0)
        
        let rect = CGRect(x: 0.0, y: 0.0, width: size.width, height: size.height)
        
        draw(context, rect)
        
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image!
    }
}

let navHeight = self.navigationController?.navigationBar.frame.height;
let menuBtn = UIButton(type: .custom)
menuBtn.frame = CGRect(x: 0, y: 0, width: 45, height: navHeight!)     
menuBtn.setImage(UIImage(named:"image_name")!.withRenderingMode(.alwaysTemplate), for: .normal)        
menuBtn.tintColor = .black

你可以在Swift 3中使用它，如果你有一个图像来替换清除按钮

func addTextfieldRightView(){

    let rightViewWidth:CGFloat = 30

    let viewMax = self.searchTxt.frame.height
    let buttonMax = self.searchTxt.frame.height - 16

    let buttonView = UIView(frame: CGRect(
        x: self.searchTxt.frame.width - rightViewWidth,
        y: 0,
        width: viewMax,
        height: viewMax))

    let myButton = UIButton(frame: CGRect(
        x: (viewMax - buttonMax) / 2,
        y: (viewMax - buttonMax) / 2,
        width: buttonMax,
        height: buttonMax))

    myButton.setImage(UIImage(named: "BlueClear")!, for: .normal)

    buttonView.addSubview(myButton)

    let clearPressed = UITapGestureRecognizer(target: self, action: #selector(SearchVC.clearPressed(sender:)))
    buttonView.isUserInteractionEnabled = true
    buttonView.addGestureRecognizer(clearPressed)

    myButton.addTarget(self, action: #selector(SearchVC.clearPressed(sender:)), for: .touchUpInside)

    self.searchTxt.rightView = buttonView
    self.searchTxt.rightViewMode = .whileEditing
}