Retrieving an image to my UIImageView - ios

I load the image using my Android application Parse in my database, and I want to show it on my iphone.
when I run the Xcode tells me: 'Could not release the value of type' NSConcreteData 'to' PFFile ''
there any way to get this image and show on my iPhone (UIImageView) ??
Any idea to help me ?
I'll be very grateful !!
enter image description here

The problem is, as the Compiler tells you, that you're trying to cast NSData to PFFile.
Just use:
let userImageProfilePicture = event["profile_picture"]
userImageProfilePicture.getDataInBackgroundWithBlock({ (data, error) -> Void in
// handle here with your userAuth == true block
if let data = data where error == nil{
var image = UIImage(data: data)
}
})

Related

Retrieve images from a DJI Drone with EXIF data

I'm using the DJISDK in iOS to download pictures from the aircraft.
I'm using the downloadSelectedFiles method from PlaybackManager class.
Here is my process callback:
process: { (data, error) in
if data != nil{
if self.downloadedImageData != nil{
self.downloadedImageData!.append(data!)
}else{
self.downloadedImageData = data!
}
}
}
And this is filecompletition callback:
fileCompletion: {
self.downloadedFilesCount += 1
let image = UIImage(data: self.downloadedImageData!)
if let img = image {
self.downloadedImagesArray?.append(img)
}
self.downloadedImageData = nil
}
I'm correctly retrieving the image but without the EXIF data. How can I get that info and add it to the image?
I already downloaded and tried the iOS-MediaManagerDemo and it's the same thing, downloads the image but without the exif data but the official DJI Go app retrieves all the info so there´s must be some way to do it.
There's also a similar issue in their forums regarding empty metadata and downloadSelectedFilesWithPreparation. The user that created the post
also found a solution:
I solved the problem by not converting the NSData into any format instead saved the NSData directly. Using PHAssets and temporary file to store the NSData as PHAssets only accepts data from URL.
Try using fetchFileDataWithOffset:updateQueue:updateBlock (it will be called fetchFileData(with:updateQueue:updateBlock) in Swift)
[...] fetching the media data will return all data for a video or image
Sample code (objc): here

MSConversation.insertAttachment with UIImage downloaded via SDWebImage

I have an iMessage app that displays some remote content using SDWebImage. The images are downloaded and cached on disk. After choosing an image, I want to attach it to the message as a plain UIImage (not a MSMessage).
Here's the code I'm using
// image is already downloaded
let cache = SDImageCache.shared()
let key = remoteImageUrl
let fileUrlString = cache.defaultCachePath(forKey: key)!
let fileUrl = URL(string: fileUrlString)!
// image holds the correct UIImage
let image = UIImage(contentsOfFile: fileUrlString)
activeConversation?.insertAttachment(fileUrl, withAlternateFilename: "a funny gif", completionHandler: { (error) in
// error is nil here
print("error: \(error)")
})
Here's what the message looks like
It seems like the Messages framework can't find the image at that path.
Note: after tapping send, I the iMessage app crashes "MobileSMS quit unexpectedly."
I found out that I needed to use
let fileUrl = URL(fileURLWithPath: fileUrlString)
Hope this helps someone else

Adding image from Firebase to UITableViewCell

I want to retrieve the image that is stored in the storage of an user and place it next to his name in a custom UITableViewCell. The problem now is that the tableview will load when the images aren't done downloading (I think?), causing the application to crash because the image array is nil. So what is the correct way to load the tableview? I think, for the user experience, it is important that the tableviewcell image should be shown even if the images aren't done downloading, and present them a default image that is saved in the assists. I thought about making an array with UIImages that links to the default asset of loading an image and changing the image to the profile picture when it is done downloading. But I really have no clue how to do that. This is what I got so far about downloading the image:
let storage = FIRStorage.storage()
let storageRef = storage.reference(forURL: "link.appspot.com")
channelRef?.observeSingleEvent(of: .value, with: { (snapshot) in
if let snapDict = snapshot.value as? [String:AnyObject]{
for each in snapDict{
let UIDs = each.value["userID"] as? String
if let allUIDS = UIDs{
let profilePicRef = storageRef.child((allUIDS)+"/profile_picture.png")
profilePicRef.data(withMaxSize: 1 * 500 * 500) { data, error in
if let error = error {
}
if (data != nil)
{
self.playerImages.append(UIImage (data: data!)!)
}
}
}
let userNames = each.value["username"] as? String
if let users = userNames{
self.players.append(users)
}
}
}
self.tableView.reloadData()
})
This is in the cellForRow
cell.playersImage.image = playerImages[indexPath.row] as UIImage
My rules, haven't changed it from the default rules:
service firebase.storage {
match /b/omega-towers-f5beb.appspot.com/o {
match /{allPaths=**} {
allow read, write: if request.auth != null;
}
}
}
Thank you.
Regarding user experience, you are correct. It is standard to have some sort of default image when loading an image from a URL. A great library to use for image caching and using default assets in its' place is AlamofireImage
Vandan Patel's answer is correct in saying you need to ensure your array is not nil when loading the tableview. You will be given a completion block to handle any extra work you would like to do with your image, using the AlamofireImage library.
This is all assuming you are getting a correct image URL back for your Firebase users.
You should call tableView.reloadData() when the images are done downloading. One important thing, initialize your playerImages as playerImages = [UIImage]() instead of playerImages: [UIImage]!. if it's empty, it wouldn't show your array is nil.
Update:
if let players = playerImages {
//code
}

Issue converting NSData to UIImage via Parse.com download

I'm having a strange issue. My app works fine in the iPhone 6 emulator, but not in any other emulators or on my iDevice. Here's the main code
query.findObjectsInBackgroundWithBlock {
(objects, error) -> Void in
if(error == nil){
let imageObjects = objects as! [PFObject]
if let myObjects = objects {
for object in myObjects {
let myTitle = object["imageName"] as! NSString
println(myTitle)
let thumbNail = object["imageFile"] as! PFFile
// println(thumbNail)
thumbNail.getDataInBackgroundWithBlock({
(imageData: NSData?, error: NSError?) -> Void in
if (error == nil) {
self.imageArray.append(imageData!)
let image = UIImage(data:imageData!)
self.imageView.contentMode = .ScaleAspectFit
self.imageView.image=image
}
})//getDataInBackgroundWithBlock - end
}//for - end
}
}//end of if
else{
println("Error in retrieving \(error)")
}
}//findObjectsInBackgroundWithblock - end
I think this line is the culprit
let image = UIImage(data:imageData!)
But I'm not sure why. "image" returns nil in all other devices except iPhone 6 emulator. Any suggestions would be awesome.
Thanks
NOTE: the image displays just fine in iPhone 6 emulator. I'm using storyboard and unchecked autolayout.
There shouldn't really be a situation where the app only works on one simulator setting. Resetting your simulator should solve the problem.
One possibility is that you previously successfully downloaded this data, and Parse has cached the response in your iPhone app, but you've since changed the PFObject remotely and removed the image data. Or perhaps changed code.
Because Parse.com caches images, it's possible that it works only on this device because of Parse.com caching.
You could use the debugger, or worse, NSLog to determine what is nil. You need to determine if imageData is coming back nil or not. Also, is there a reason why you're assuming imageData is non-null? I'm referring to references to imageData! -- that seems dangerous. Just because there's no error doesn't mean imageData is non-null.

Unable to edit screenshots, performChanges block fails

I'm developing an app that allows users to edit photos using PhotoKit. I was previously saving the edited photo to disk as a JPEG. I would like to avoid converting to JPEG and have implemented the modifications in order to do that. It works great for photos taken with the camera, but if you try to edit a screenshot, the PHPhotoLibrary.sharedPhotoLibrary().performChanges block will fail and log The operation couldn’t be completed. (Cocoa error -1.). I am not sure why this is causing the performChanges block to fail, what have I done wrong here?
I've created a sample app available to download that demonstrates the problem, and I've included the relevant code below. The app attempts to edit the newest photo in your photo library. If it succeeds it will prompt for access to edit the photo, otherwise nothing will happen and you'll see the console log. To reproduce the issue, take a screenshot then run the app.
Current code that works with screenshots:
let jpegData: NSData = outputPhoto.jpegRepresentationWithCompressionQuality(0.9)
let contentEditingOutput = PHContentEditingOutput(contentEditingInput: self.input)
var error: NSError?
let success = jpegData.writeToURL(contentEditingOutput.renderedContentURL, options: NSDataWritingOptions.AtomicWrite, error: &error)
if success {
return contentEditingOutput
} else {
return nil
}
Replacement code that causes screenshots to fail:
let url = self.input.fullSizeImageURL
let orientation = self.input.fullSizeImageOrientation
var inputImage = CIImage(contentsOfURL: url)
inputImage = inputImage.imageByApplyingOrientation(orientation)
let outputPhoto = createOutputImageFromInputImage(inputImage)!
let originalImageData = NSData(contentsOfURL: self.input.fullSizeImageURL)!
let imageSource = CGImageSourceCreateWithData(originalImageData, nil)
let dataRef = CFDataCreateMutable(nil, 0)
let destination = CGImageDestinationCreateWithData(dataRef, CGImageSourceGetType(imageSource), 1, nil) //getType automatically selects JPG, PNG, etc based on original format
struct ContextStruct {
static var ciContext: CIContext? = nil
}
if ContextStruct.ciContext == nil {
let eaglContext = EAGLContext(API: .OpenGLES2)
ContextStruct.ciContext = CIContext(EAGLContext: eaglContext)
}
let cgImage = ContextStruct.ciContext!.createCGImage(outputPhoto, fromRect: outputPhoto.extent())
CGImageDestinationAddImage(destination, cgImage, nil)
if CGImageDestinationFinalize(destination) {
let contentEditingOutput = PHContentEditingOutput(contentEditingInput: self.input)
var error: NSError?
let imageData: NSData = dataRef
let success = imageData.writeToURL(contentEditingOutput.renderedContentURL, options: .AtomicWrite, error: &error)
if success {
//it does succeed
return contentEditingOutput
} else {
return nil
}
}
The problem happens due to the fact that adjusted photos are always saved as JPG files, and screenshots are in fact PNG files.
It occurred to me while I was debugging your sample project and saw the in the PhotoEditor, contentEditingOutput.renderedContentURL is a URL to a JPG, while if you examine the result of CGImageSourceGetType(imageSource) it is clear the it's a PNG (returns a PNG UTI: public.png).
So I went and read the documentation for renderedContentURL which states that if editing a photo asset, the altered image is written in JPEG format - which clearly won't work if your image is a PNG. This leads me to think that Apple don't support editing PNG files or don't want you to. Go figure..

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