0
我正在研究解釋一些醫療術語及其細節的醫療應用程序。我必須處理幾個操作以下載圖像和一些音頻文件。我有兩個類分別處理圖像下載和音頻下載的網絡操作和緩存操作。我已經使用AFNetworking來處理所有的操作，我正在使用Swift。該場景是在應用程序啓動時，我打電話給圖像類的函數來下載所有圖像，並在各自的視圖控制器上查看術語詳細信息，我可以選擇播放音頻文件（如果可用）。但是，如果我點擊播放按鈕，只有在下載了從應用程序代理處理的所有圖像（例如：20張圖像）後纔會下載音頻。在不同視圖中使用操作時的延遲
import UIKit
let ImageFileDirectory : String = "Image-cache"
typealias ImageDownloadCallBackSuccess = (String , UIImage) -> Void
class ImageManager: NSObject {
override init() {
super.init()
}
func downloadImageFile (imageData : Dictionary<String,AnyObject>, callback: ImageDownloadCallBackSuccess) -> Void {
let imageUrl : NSString = (imageData as NSDictionary).objectForKey("url") as! NSString
let imageId : Int = (imageData as NSDictionary).objectForKey("id") as! Int
let imageIDString : String = String(imageId)
let filemanager = NSFileManager.defaultManager()
if !filemanager.fileExistsAtPath(filePath(imageIDString)) {
var opManager : AFHTTPRequestOperationManager = AFHTTPRequestOperationManager()
opManager.responseSerializer = AFImageResponseSerializer()
opManager.requestSerializer.timeoutInterval = 180.0
let newOperation = opManager.HTTPRequestOperationWithRequest(NSURLRequest(URL: NSURL(string: imageUrl)!), success: { (operation: AFHTTPRequestOperation!,responseObject: AnyObject!) -> Void in
println("File Saved to ImageCacheDirectory")
let imageData : NSData = UIImageJPEGRepresentation(responseObject as! UIImage, 1.0)
imageData.writeToFile(self.filePath(imageIDString), atomically: true)
callback(imageIDString, responseObject as! UIImage)
}, failure: { (operation: AFHTTPRequestOperation!,error: NSError!) -> Void in
println("Couldn't save the file to ImageCacheDirectory")
})
newOperation.start()
}
else {
println("file exist for path")
}
}
class func filePathForImage (imageID: String) -> (String!) {
let documentsPath : String = NSSearchPathForDirectoriesInDomains(.DocumentDirectory,.UserDomainMask,true)[0] as! String
let fileExtensionString = String(format:"/%@/", ImageFileDirectory)
let folderPath = documentsPath.stringByAppendingPathComponent("\(fileExtensionString)")
let filemanager = NSFileManager.defaultManager()
var err: NSErrorPointer = nil
if !filemanager.fileExistsAtPath(folderPath) {
filemanager.createDirectoryAtPath(folderPath, withIntermediateDirectories: true, attributes: nil, error: err)
}
var filePath = "\(folderPath)"
filePath += "/"
filePath += "\(imageID)"
filePath += "."
filePath += "jpg"
return filePath
}
func imageRootDirectory() -> String {
let documentsPath : String = NSSearchPathForDirectoriesInDomains(.DocumentDirectory,.UserDomainMask,true)[0] as! String
let imageDirectory = String(format:"/%@/", ImageFileDirectory)
return documentsPath.stringByAppendingPathComponent("\(imageDirectory)")
}
func filePath (imageID :String) -> String {
let folderPath = imageRootDirectory()
var filePath = "\(folderPath)"
filePath += "/"
filePath += "\(imageID)"
filePath += "."
filePath += "jpg"
return filePath
}
func downloadAllImage() {
for imageObject in DataManager.sharedInstance.allImages {
downloadImageFile(imageObject, callback: { (imageString, imageData) -> Void in
})
}
}
}
typealias AudioDownloadHandler = (Double) -> Void
let AudioFileDirectory : String = "Audio-cache"
import UIKit
import AVFoundation
class AudioManager: NSObject ,AVAudioPlayerDelegate {
var audioID : Int?
var audioUrl : String?
var audioPlayer : AVAudioPlayer! // will be Optional, must supply initializer
override init() {
super.init()
}
init (audioId : Int , audioUrl: String) {
self.audioUrl = audioUrl
self.audioID = audioId
super.init()
}
func cacheAudioFile(callback:AudioDownloadHandler) -> Void {
let request: NSURLRequest = NSURLRequest(URL: NSURL(string: self.audioUrl!)!)
let audioDownloadOperation: AFHTTPRequestOperation = AFHTTPRequestOperation(request: request)
audioDownloadOperation.outputStream = NSOutputStream(toFileAtPath: filePathForAudio()!, append: false)
audioDownloadOperation.setDownloadProgressBlock({(bytesRead, totalBytesRead, totalBytesExpectedToRead) -> Void in
var total: CGFloat = CGFloat(totalBytesRead)/CGFloat(totalBytesExpectedToRead)
callback(Double(total))
})
audioDownloadOperation.start()
}
func filePathForAudio() -> (String!) {
let documentsPath : String = NSSearchPathForDirectoriesInDomains(.DocumentDirectory,.UserDomainMask,true)[0] as! String
let fileExtensionString = String(format:"/%@/", AudioFileDirectory)
let folderPath = documentsPath.stringByAppendingPathComponent("\(fileExtensionString)")
let filemanager = NSFileManager.defaultManager()
var err: NSErrorPointer = nil
if !filemanager.fileExistsAtPath(folderPath) {
filemanager.createDirectoryAtPath(folderPath, withIntermediateDirectories: true, attributes: nil, error: err)
}
var filePath = "\(folderPath)"
filePath += "/"
filePath += "\(self.audioID!)"
filePath += "."
filePath += "\(self.audioUrl!.pathExtension)"
return filePath
}
func playAudioFile() {
var filePathUrl : NSURL = NSURL.fileURLWithPath(filePathForAudio())!
var error: NSError!
self.audioPlayer = AVAudioPlayer(contentsOfURL: filePathUrl, error: nil)
self.audioPlayer.delegate = self
if let player : AVAudioPlayer = self.audioPlayer as AVAudioPlayer?{
self.audioPlayer.prepareToPlay()
player.play()
}
}
func audioPlayerDidFinishPlaying(player: AVAudioPlayer!, successfully flag: Bool) {
NSNotificationCenter.defaultCenter().postNotificationName("AudioFinishedPlaying", object: nil)
}
}
let imageManager = ImageManager()
imageManager.downloadAllImage()
那麼你的問題是什麼？ –
@DuncanC使用我的代碼進行操作管理有任何問題。 – Nassif
無關，但我不會建議使用'AFImageResponseSerializer'，然後使用'UIImageJPEGRepresentation'重新創建'NSData'，以便（a）可能使其變大;和（b）在這個過程中可能丟失元數據。您可以通過查看操作的'responseData'屬性來獲得原始的'NSData'。或者使用標準的'AFHTTPResponseSerializer'，然後將它自己轉換爲'UIImage'。無論哪種方式，請保存原始響應數據，而不是從圖像中重新提取。 – Rob