how to Retrieve image stored in firebase to show i

问题:

i am facing a problem with how to retrieve an image stored in firebase here is the code i used to store the image :

@IBAction func AddDeviceButton(sender: AnyObject) {
    if DeviceName.text == "" || Description.text == "" || ImageView.image == nil {
        let alert = UIAlertController(title: "عذرًا", message:"يجب عليك تعبئة معلومات الجهاز كاملة", preferredStyle: .Alert)
        alert.addAction(UIAlertAction(title: "نعم", style: .Default) { _ in })
        self.presentViewController(alert, animated: true){}

    } else {

        let imageName = NSUUID().UUIDString
        let storageRef = FIRStorage.storage().reference().child("Devices_Images").child("\(imageName).png")

        let metaData = FIRStorageMetadata()
        metaData.contentType = "image/png"

        if let uploadData = UIImagePNGRepresentation(self.ImageView.image!) {
            storageRef.putData(uploadData, metadata: metaData, completion: { (data, error) in
                if error != nil {
                    print(error)

                } else {
                    print("Image Uploaded Succesfully")
                    let profileImageUrl = data?.downloadURL()?.absoluteString

                    //

                    let DeviceInfo = [
                        "ImageUrl":profileImageUrl!,
                        "DeviceName":self.DeviceName.text!,
                        "Description":self.Description.text!,
                        "Category":self.itemSelected
                    ]

                    let DeviceInformation = [
                        "ImageUrl":profileImageUrl!,
                        "DeviceName":self.DeviceName.text!,
                        "Description":self.Description.text!,
                        "Category":self.itemSelected,
                        "name": self.globalUserName,
                        "email":self.globalEmail ,
                        "city": self.globalCity,
                        "phone": self.globalPhone
                    ]


                    self.ref.child("Devices").child(FIRAuth.auth()!.currentUser!.uid).observeSingleEventOfType(.Value, withBlock: {(snapShot) in
                        if snapShot.exists(){
                            let numberOfDevicesAlreadyInTheDB = snapShot.childrenCount
                            if numberOfDevicesAlreadyInTheDB < 3{
                                let newDevice = String("Device\(numberOfDevicesAlreadyInTheDB+1)")
                                let userDeviceRef = self.ref.child("Devices").child(FIRAuth.auth()!.currentUser!.uid)
                                userDeviceRef.observeSingleEventOfType(.Value, withBlock: {(userDevices) in
                                    if let userDeviceDict = userDevices.value as? NSMutableDictionary{

                                        userDeviceDict.setObject(DeviceInfo,forKey: newDevice)

                                        userDeviceRef.setValue(userDeviceDict)
                                    }
                                })
                            }
                            else{
                                let alert = UIAlertController(title: "عذرًا", message:"يمكنك إضافة ثلاثة أجهزة فقط كحد أقصى", preferredStyle: .Alert)
                                alert.addAction(UIAlertAction(title: "نعم", style: .Default) { _ in })
                                self.presentViewController(alert, animated: true){}
                            }
                        }else{
                          self.ref.child("Devices").child(FIRAuth.auth()!.currentUser!.uid).setValue(["Device1" : DeviceInfo])
                             self.ref.child("UserDevices").childByAutoId().setValue(DeviceInformation)

                        }
                    })

                    //

                } })
        }


    } //Big Big Else

} //AddDeviceButton

i just wanna load the images to user profile from the firebase storage so that every time user logged into his profile he can see all images he uploads to the application

回答1:

We highly recommend using Firebase Storage and the Firebase Realtime Database together to accomplish this. Here's a full example:

Shared:

// Firebase services
var database: FIRDatabase!
var storage: FIRStorage!
...
// Initialize Database, Auth, Storage
database = FIRDatabase.database()
storage = FIRStorage.storage()
...
// Initialize an array for your pictures
var picArray: [UIImage]()
let myUserId = ... // get this from Firebase Auth or some other ID provider

Upload:

let fileData = NSData() // get data...
let storageRef = storage.reference().child("userFiles/\(myUserId)/myFile")
storageRef.putData(fileData).observeStatus(.Success) { (snapshot) in
  // When the image has successfully uploaded, we get it's download URL
  let downloadURL = snapshot.metadata?.downloadURL()?.absoluteString
  // Write the download URL to the Realtime Database
  let dbRef = database.reference().child("userFiles/\(myUserId)/myFile")
  dbRef.setValue(downloadURL)
}

Download:

let dbRef = database.reference().child("userFiles/\(myUserId)")
dbRef.observeEventType(.ChildAdded, withBlock: { (snapshot) in
  // Get download URL from snapshot
  let downloadURL = snapshot.value() as! String
  // Create a storage reference from the URL
  let storageRef = storage.referenceFromURL(downloadURL)
  // Download the data, assuming a max size of 1MB (you can change this as necessary)
  storageRef.dataWithMaxSize(1 * 1024 * 1024) { (data, error) -> Void in
    // Create a UIImage, add it to the array
    let pic = UIImage(data: data)
    picArray.append(pic)
  })
})

For more information, see Zero to App: Develop with Firebase, and it's associated source code, for a practical example of how to do this.