IOS用名字保存图片

Question

我有一个应用程序可以拍照并将其与另一张图像合并。我希望能够显示在应用程序（并且只有我的应用程序）中拍摄的所有图像并将它们显示在图库视图中。我遇到的问题是为图像分配名称。

我尝试了很多不同的方法

第一次尝试

UIImageWriteToSavedPhotosAlbum(newImage, nil, nil, nil)

这保存了图像，但我不知道如何检索它

第二次尝试

PHPhotoLibrary.sharedPhotoLibrary().performChanges({
    let assetRequest = PHAssetChangeRequest.creationRequestForAssetFromImage(newImage)

    }, completionHandler: { (success, error) -> Void in
        if success {
            //image saved to photos library.
            print("image saved")
        }
});

与第一次尝试相同的问题

第三次尝试

let date :NSDate = NSDate()

let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'_'HH:mm:ss"
dateFormatter.timeZone = NSTimeZone(name: "GMT")

let imageName = "\(dateFormatter.stringFromDate(date)).jpg"

//var paths: [AnyObject] = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, true)
var documentsDirectoryPath = getDocumentsURL().relativePath
documentsDirectoryPath! += imageName

let settingsData: NSData = UIImageJPEGRepresentation(newImage, 1.0)!
settingsData.writeToFile(documentsDirectoryPath!, atomically: true)

这似乎是最有希望的，但文件确实会自动保存

我在这里查看了各种答案，但我仍然无法确定解决方案

Answer 1

添加一个斜杠作为 imageName 字符串的第一个字符，如下所示：

let imageName = "/\(dateFormatter.stringFromDate(date)).jpg"

否则路径将是“..../Documentsmyimagename”，但应该是“..../Documents/myimagename” 即没有附加斜线，图像将保存到“文档”上方的文件夹中

我还建议不要在文件名中使用冒号字符，在 mac 上，冒号是不允许的，并且会自动替换。

这是我在一个新的 XCode 项目中测试的代码，它对我有用（我在项目的根文件夹中放置了一个文件“myimage.png”）：

let newImage = UIImage.init(named: "myimage")


        let date :NSDate = NSDate()

        let dateFormatter = NSDateFormatter()
        //dateFormatter.dateFormat = "yyyy-MM-dd'_'HH:mm:ss"
        dateFormatter.dateFormat = "yyyy-MM-dd'_'HH_mm_ss"

        dateFormatter.timeZone = NSTimeZone(name: "GMT")

        let imageName = "/\(dateFormatter.stringFromDate(date)).jpg"
        print(imageName)
        //var paths: [AnyObject] = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, true)
        //var documentsDirectoryPath = getDocumentsURL().relativePath
        var documentsDirectoryPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] 
        documentsDirectoryPath += imageName
        print(documentsDirectoryPath)

        let settingsData: NSData = UIImageJPEGRepresentation(newImage!, 1.0)!
        settingsData.writeToFile(documentsDirectoryPath, atomically: true)

Answer 2

SWIFT 3 :)

import UIKit

class ShowImageViewController: UIViewController {

@IBOutlet weak var mainImageView: UIImageView!
@IBOutlet weak var tempImageView: UIImageView!

private var lastPoint = CGPoint.zero
private var red: CGFloat = 0.0
private var green: CGFloat = 0.0
private var blue: CGFloat = 0.0
private var brushWidth: CGFloat = 10.0
private var opacity: CGFloat = 1.0
private var swiped = false


override func viewDidLoad() {
    super.viewDidLoad()
    mainImageView.image = captureImages[selectedImageindex]
    tempImageView.frame = getImageRect(for: mainImageView)

    // Do any additional setup after loading the view.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    swiped = false
    if let touch = touches.first {
        lastPoint = touch.location(in: tempImageView)
    }
}

override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
    swiped = true
    if let touch = touches.first {
        let currentPoint = touch.location(in: tempImageView)
        drawLineFrom(fromPoint: lastPoint, toPoint: currentPoint)

        lastPoint = currentPoint
    }
}

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
    if !swiped {
        drawLineFrom(fromPoint: lastPoint, toPoint: lastPoint)
    }

    // Merge tempImageView into mainImageView
    UIGraphicsBeginImageContext(mainImageView.frame.size)
    mainImageView.image?.draw(in: CGRect(x: 0, y: 0, width: mainImageView.frame.size.width, height: mainImageView.frame.size.height), blendMode: .normal, alpha: 1.0)
    tempImageView.image?.draw(in: CGRect(x: 0, y: 0, width: mainImageView.frame.size.width, height: mainImageView.frame.size.height), blendMode: .normal, alpha: opacity)
    mainImageView.image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    tempImageView.image = nil
}

func drawLineFrom(fromPoint: CGPoint, toPoint: CGPoint) {
    UIGraphicsBeginImageContext(mainImageView.frame.size)
    let context = UIGraphicsGetCurrentContext()
    tempImageView.image?.draw(in: CGRect(x: 0, y: 0, width: mainImageView.frame.size.width, height: mainImageView.frame.size.height))

    context!.move(to: CGPoint(x: fromPoint.x, y: fromPoint.y))
    context!.addLine(to: CGPoint(x: toPoint.x, y: toPoint.y))
    context!.setLineCap(.round)
    context!.setLineWidth(brushWidth)
    context!.setStrokeColor(red: red, green: green, blue: blue, alpha: 1.0)
    context!.setBlendMode(.normal)

    context!.strokePath()

    tempImageView.image = UIGraphicsGetImageFromCurrentImageContext()
    tempImageView.alpha = opacity
    UIGraphicsEndImageContext()

}

func getImageRect(for imageView: UIImageView) -> CGRect {
    let resVi =  (imageView.image?.size.width)! / (imageView.image?.size.height)!
    let resPl =     imageView.frame.size.width / imageView.frame.size.height
    if resPl > resVi {
        let imageSize = CGSize(width: CGFloat((imageView.image?.size.width)! * imageView.frame.size.height / (imageView.image?.size.height)!), height: CGFloat(imageView.frame.size.height))
        return CGRect(x: CGFloat((imageView.frame.size.width - imageSize.width) / 2), y: CGFloat((imageView.frame.size.height - imageSize.height) / 2), width: CGFloat(imageSize.width), height: CGFloat(imageSize.height))
    }
    else {
        let imageSize = CGSize(width: CGFloat(imageView.frame.size.width), height: CGFloat((imageView.image?.size.height)! * imageView.frame.size.width / (imageView.image?.size.width)!))
        return CGRect(x: CGFloat((imageView.frame.size.width - imageSize.width) / 2), y: CGFloat((imageView.frame.size.height - imageSize.height) / 2), width: CGFloat(imageSize.width), height: CGFloat(imageSize.height))
    }
}
}