iOS:在 uicollectionview 中添加 UIProgressView 以显示上传到 firebase 存储的上传百分比

Question

我正在开发一个将图像列表上传到 firebase 存储的 iOS 应用程序，我需要在 uicollectionview 的每个单元格内放置一个进度 View (显示数据源中的每个图像)以指示将此图像上传到 firebase 存储的百分比.

我试试这段代码:

func Upload(imageView: UIImageView)
{
    // Data in memory
    var data = Data()
    data = UIImageJPEGRepresentation(self.pickedImage, 0.8)!

    // Create a root reference
    let storageRef = Storage.storage().reference()
    let imageName = NSUUID().uuidString

    // Create a reference to the file you want to upload
    let imageRef = storageRef.child("images/\(imageName).jpg")

    // Upload the file to the path "images/rivers.jpg"
    let uploadTask = imageRef.putData(data, metadata: nil) { (metadata, error) in
        guard let metadata = metadata else {
            // Uh-oh, an error occurred!
            return
        }
    }

    let observer = uploadTask.observe(.progress) { snapshot in
        print("snapshot.progress",snapshot.progress) 
    }

    uploadTask.observe(.progress) { snapshot in
        let percentComplete = 100.0 * Double(snapshot.progress!.completedUnitCount)
            / Double(snapshot.progress!.totalUnitCount)
        print("percentComplete",percentComplete)
        let placeholderImage = UIImage(named: "la")
        imageView.sd_addActivityIndicator()
        imageView.sd_showActivityIndicatorView()
        imageView.sd_setImage(with: imageRef, placeholderImage: placeholderImage)
    }

    uploadTask.observe(.success) { snapshot in
       self.url = imageName
        print(imageName)
        print("success")
        imageView.sd_removeActivityIndicator()
    }
     uploadTask.observe(.failure) { snapshot in
        print("Failuer")
    }
}

和:

arrayOfImages?[(arrayOfImages?.count)! - 1]?.Upload(imageView: cell.workImage)

但我无法得到它，因为在 UICollectionView 中重用了单元格，我怎样才能得到它？

Answer 1

1- 创建一个类并将这段代码粘贴到一个函数中

2- 在该类中创建进度属性，并在进度完成和图像的另一个属性中定期更新它

3- 在类中创建一个实例数组并用图像初始化它并开始上传

4- 在 cellForRowAt 中获取每个索引的当前进度值，这就是避免单元格重复使用和上传已上传或当前正在上传的图像的方法

//

应该是这样的

class Upload {

    var currentState:State = .none

    var progress:Float = 0

    var img:UIImage

    init(image:UIImage) {

        img = image


    }

    func start () {

        currentState = .uploading

        ///

        let observer = uploadTask.observe(.progress) { snapshot in
            self.progress = snapshot.progress
        }

        ///


         uploadTask.observe(.success) { snapshot in
            currentState = .uploaded
         }

        //

    }


}

enum State {

    case uploading,uploaded,none
}

//

var arr = [Upload]()

for i in 0..<numberOfImages {

    let img = UIImage(named: "\(i).png") // or get it anyWay

    let up = Upload(image: img)

    up.start() // start it in cellForRowAt if item state is none

    arr.append(up)

}