截屏、圆角、保存相册

图片圆角

具体方法和画图操作基本差不过，主要分为以下几个步骤

1. 开启图片下上文

UIGraphicsBeginImageContextWithOptions(img.size, false, 0.0)

1. 描述路径

let path: UIBezierPath = UIBezierPath.init(ovalIn: CGRect(x: 0,y: 0,width: img.size.width,height: img.size.height))

1. 开始剪切

path.addClip()

1. 开始绘制

img.draw(at: CGPoint(x: 0,y: 0))

1. 生成图片

let newImg: UIImage = UIGraphicsGetImageFromCurrentImageContext()!

1. 关闭路径

UIGraphicsEndImageContext()

以下为封装的方法

/// 图片圆角
///
/// - Parameter img: 传入图片
/// - Returns: 传出新图片
static func imgeRoundedCorners(img: UIImage) -> UIImage{

UIGraphicsBeginImageContextWithOptions(img.size, false, 0.0)
let path: UIBezierPath = UIBezierPath.init(ovalIn: CGRect(x: 0,y: 0,width: img.size.width,height: img.size.height))
path.addClip()
img.draw(at: CGPoint(x: 0,y: 0))

let newImg: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()

return newImg
}

图片边框圆角

/// 带边框的图片圆角
///
/// - Parameters:
/// - img: 图片
/// - space: 边框间隔
/// - color: 边框颜色
/// - Returns: 返回生成的新图片
static func imgBorderRoundedCorners(img: UIImage, space: CGFloat, color: UIColor) -> UIImage{

let imgSize: CGSize = CGSize(width: img.size.width + 2 * space, height: img.size.height + 2 * space)


UIGraphicsBeginImageContextWithOptions(imgSize, false, 0.0)
let path: UIBezierPath = UIBezierPath.init(ovalIn: CGRect(x: 0,y: 0,width: imgSize.width,height: imgSize.height))

color.set()
path.fill()

let path1: UIBezierPath = UIBezierPath.init(ovalIn: CGRect(x: space, y: space, width: img.size.width, height: img.size.height))

path1.addClip()
img.draw(at: CGPoint(x: space,y: space))

let newImg: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()

return newImg
}

屏幕截屏

/// 截屏
///
/// - Parameters:
/// - size: 截屏的大小
/// - view: 在那个View上截屏
/// - Returns: 返回一个图片
static func imgScreenshots(size: CGSize, in view: UIView) -> UIImage {

UIGraphicsBeginImageContextWithOptions(size, false, 0.0)
// 离屏渲染
view.layer.render(in: UIGraphicsGetCurrentContext()!)

let imgNew: UIImage = UIGraphicsGetImageFromCurrentImageContext()!

UIGraphicsEndImageContext()

return imgNew
}

保存图片的多种方式

1. UIImageWriteToSavedPhotosAlbum函数

//保存到相册的图片对象
//保存完成功后回调的目标对象
//保存完成后回调的方法
//保存完成后，会回调方法的contextinfo中
UIImageWriteToSavedPhotosAlbum(imgNew, self, #selector(imgSaveDidFinish(img:error:)), nil)

//保存成功后回调方法
@objc func imgSaveDidFinish(img: UIImage, error: NSError) {

}

2. 使用Photos框架下的PHPPhotoLibrary类来实现保存

import Photos //导入模块

PHPhotoLibrary.shared().performChanges({
//写入相册
PHAssetChangeRequest.creationRequestForAsset(from: imgNew)
}) { (success, error) in
print("成功： \(success) 错误：\(String(describing: error))")
}