I'm getting this behaviour using Xcode 8.0. The problem is, after downloading a file and storing it on documents directory (code provided below), QLPreviewController only displays document's name and size. The property currentPreviewItem returns the correct path document. What's even more strange, is that if I try to open that document from another controller in my app, it works fine. I've implemented both QLPreviewControllerDelegate and QLPreviewControllerDataSource.
Code for downloading and saving document:
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
NSURL *url = [NSURL URLWithString:file[#"url"]];
NSData *data = [NSData dataWithContentsOfURL:url];
if (!data) {
completion([NSError new]);
return;
}
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:AppName];
path = [path stringByAppendingPathComponent:file[#"name"]];
file[#"filePath"] = [NSURL fileURLWithPath:path];
dispatch_async(dispatch_get_main_queue(), ^{
[[NSFileManager defaultManager] createFileAtPath:path contents:data attributes:nil];
completion(nil);
});
});
Then, when user selects a document I use the content saved on #"filePath" to show QLPreviewController. I've tried pushing it and presenting it modally and in both cases it just displays a gray page with document's name and size.
File wasn't showed because downloaded contents didn't contain file's extension. When I tried opening it in other controller, it worked because I temporary used another file name containing the correct extension. So I solved the problem adding the extension .pdf to downloaded files that didn't include it. This made QLViewController displaying correctly the file.
In my case, a file was created with the correct name, but the file contained an error message from the server, thus not representing the expected file structure.
Related
Hi I'm new to iOS objective c.
I'm working on a app which fetches images and stores it in the app memory for reference.
when u click on the favourite it should go the favourites tab
when clicked on downloads.The image should go on the download tab.
as ALAasset is deprecated can some one explain what is the best way to store images.
is it using file or PHImagemanager.
and how?
You should store images in documents directory something like,
NSString *docsDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)objectAtIndex:0];
NSString *documentsDirectoryForSaveImages = [docsDir stringByAppendingPathComponent:#"/ProfileImages"];
[[NSFileManager defaultManager] createDirectoryAtPath:documentsDirectoryForSaveImages withIntermediateDirectories:YES attributes:nil error:nil]; // This creates folder in document directory of name "ProfileImages"
Now you can store image something like,
NSData *data = UIImageJPEGRepresentation(responseObject, 1.0); //Convert image to data
[data writeToFile:[documentsDirectoryForSaveImages stringByAppendingPathComponent:formImage] atomically:NO]; //write that data to path. formImage is string value (name of image. Ideally should use timestamp to make unique naming)
You can retrieve image something like,
UIImage *img = [UIImage imageWithContentsOfFile:[documentsDirectoryForSaveImages stringByAppendingPathComponent:formImage]];
Hope this will help :)
I use this code to save some PDF data to a file, send it to another app using the "Open In" menu, then delete the file when that's done:
- (void)openIn:(NSData *)fileData {
// save the PDF data to a temporary file
NSString *fileName = [NSString stringWithFormat:#"%#.pdf", self.name];
NSString *filePath = [NSString stringWithFormat:#"%#/Documents/%#", NSHomeDirectory(), fileName];
BOOL result = [fileData writeToFile:filePath atomically:TRUE];
if (result) {
NSURL *URL = [NSURL fileURLWithPath:filePath];
UIDocumentInteractionController *controller = [[UIDocumentInteractionController interactionControllerWithURL:URL] retain];
controller.delegate = self;
[controller presentOpenInMenuFromBarButtonItem:self.openInButton animated:TRUE];
}
}
- (void)documentInteractionControllerDidDismissOpenInMenu:(UIDocumentInteractionController *)controller {
// when the document interaction controller finishes, delete the temporary file
NSString *fileName = [NSString stringWithFormat:#"%#.pdf", self.name];
NSString *filePath = [NSString stringWithFormat:#"%#/Documents/%#", NSHomeDirectory(), fileName];
[[NSFileManager defaultManager] removeItemAtPath:filePath error:nil];
}
This has worked fine until iOS 8. Now, the file is created and I can verify that it contains the correct content, the Open In menu appears, I can select an app, and the delegate method runs and cleans up the file. But instead of iOS switching to the selected app and copying the file into it as it did before, the Open In menu simply closes when I select an app, and the file is not copied.
This works if I give the UIDocumentInteractionController an existing file. It also works if I use the provided fileData but change the destination filename to the filename of an existing file. This suggests a permissions problem -- as if new files are created in iOS 8 with default permissions that UIDocumentInteractionController can't read.
Does anyone know what's happening and how I can work around it?
It looks like the order of operations has changed slightly in iOS 8. DidDismissOpenInMenu used to run after the file was finished sending, but now it runs after the file begins sending. This means my cleanup code was sometimes running before the file was finished sending, leaving no file to send. I figured this out after noticing that smaller files were being sent okay; apparently the processing for smaller files was finishing before my cleanup code got them, but the processing for larger files was not.
To ensure the correct timing, but also clean up files that are created when the user opens the DocumentInteractionController and then dismisses the controller without doing anything, I changed my methods like this:
- (void)openIn:(NSData *)fileData {
// save the PDF data to a temporary file
NSString *fileName = [NSString stringWithFormat:#"%#.pdf", self.name];
NSString *filePath = [NSString stringWithFormat:#"%#/Documents/%#", NSHomeDirectory(), fileName];
BOOL result = [fileData writeToFile:filePath atomically:TRUE];
if (result) {
self.sendingFile = FALSE;
NSURL *URL = [NSURL fileURLWithPath:filePath];
UIDocumentInteractionController *controller = [[UIDocumentInteractionController interactionControllerWithURL:URL] retain];
controller.delegate = self;
[controller presentOpenInMenuFromBarButtonItem:self.openInButton animated:TRUE];
}
}
- (void)documentInteractionController:(UIDocumentInteractionController *)controller willBeginSendingToApplication:(NSString *)application {
// the user chose to send the file, so we shouldn't clean it up until that's done
self.sendingFile = TRUE;
}
- (void)documentInteractionControllerDidDismissOpenInMenu:(UIDocumentInteractionController *)controller {
if (!self.sendingFile) {
// the user didn't choose to send the file, so we can clean it up now
[self openInCleanup];
}
}
- (void)documentInteractionController:(UIDocumentInteractionController *)controller didEndSendingToApplication:(NSString *)application {
// the user chose to send the file, and the sending is finished, so we can clean it up now
[self openInCleanup];
self.sendingFile = FALSE;
}
- (void)openInCleanup {
// delete the temporary file
NSString *fileName = [NSString stringWithFormat:#"%#.pdf", self.name];
NSString *filePath = [NSString stringWithFormat:#"%#/Documents/%#", NSHomeDirectory(), fileName];
[[NSFileManager defaultManager] removeItemAtPath:filePath error:nil];
}
Update for iOS 11
Before iOS 11, it seems that the operating system kept a copy of the file available until the receiving app was finished reading it, even though my cleanup function ran as soon as the file was sent out from my app. In iOS 11, this changed and the receiving app fails to read the file because my app deletes it before that's done. So now instead of saving the temporary file to Documents and using the openInCleanup method to delete it immediately, I'm saving the temporary file to tmp and emptying the tmp folder next time the app launches. This approach should also work with older iOS versions. Just remove openInCleanup, change Documents to tmp in the paths, and add this to applicationDidFinishLaunching:
// clear the tmp directory, which will contain any files saved for Open In
NSString *tmpDirectory = [NSString stringWithFormat:#"%#/tmp", NSHomeDirectory()];
NSArray *tmpFiles = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:tmpDirectory error:NULL];
for (NSString *tmpFile in tmpFiles) {
[[NSFileManager defaultManager] removeItemAtPath:[NSString stringWithFormat:#"%#/%#", tmpDirectory, tmpFile] error:NULL];
}
After reading this post, I already hoped to have found the solution to a similar problem:
For me, as of iOS 8, sharing was only working with Mail.app. It was failing for Dropbox, etc.
Turns out it was something else:
On my interactionController I was setting an annotation like this:
interactionController.annotation = #"Some text"
For unknown reasons, this prevented Dropbox to open at all. There were no error messages or anything. Removing this line solved the issue.
I am having some troubles saving images path into Documents folder and store the path into my sqlite3 local db.
Today I successfully stored the images as BLOB into the db, but reading around the Internet, people said that this is not recommended.
So, now I'm trying to store image path in DB but..
Situation
User taps a button to choose an image (via UIImagePickerView) or take a new photo
After choosing the image, an imageView is set with the image chosen.
Code for picker:
-(void)imagePickerController:(UIImagePickerController *)pickr didFinishPickingMediaWithInfo:(NSDictionary *)info{
UIImage *image = [info objectForKey:UIImagePickerControllerEditedImage];
/* Test code for saving data */
//NSString *dir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
//NSString *pngPath = [NSString stringWithFormat:#"%#/test.png",dir];
//NSData *data = [NSData dataWithData:UIImagePNGRepresentation(image)];
//[data writeToFile:pngPath atomically:YES];
[imageView setImage:image];
picture = YES;
[pickr dismissModalViewControllerAnimated:YES];
}
Now I got a couple of questions
Into my db, image is BLOB type. Should I edit it to TEXT?
How is the path saved? I mean, in the test code /test.png is a generic image name. Does the chosen image name get saved too so that I can retrieve it? Or, better, if I save an image picked from my library with name "IMG0001", does it get saved as "test"?
What's the right way to save an image into documents folder, its path to the DB and then retrieve it?
I googled a lot to find an answer, but after experimenting a lot I gave up.
Thanks in advance
Here is nice tutorial on how to save images in Documents directory
You need to convert your BLOB field to TEXT field and just save file name of that image. You can also create folder in Documents directory and then access by foldername/filename.png.
Hope this information helps you..
EDIT
Here is code to check if that folder exits, If not exist create new that folder
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentsDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents folder
NSString *dataPath = [documentsDirectory stringByAppendingPathComponent:#"MyFolder"];
if (![[NSFileManager defaultManager] fileExistsAtPath:dataPath]){
NSError* error;
if( [[NSFileManager defaultManager] createDirectoryAtPath:dataPath withIntermediateDirectories:NO attributes:nil error:&error])
;// success
else
{
NSLog(#"[%#] ERROR: attempting to write create MyFolder directory", [self class]);
NSAssert( FALSE, #"Failed to create directory maybe out of disk space?");
}
}
You cannot directly access the image from the user's photo library, since you have access only to your Applications Sandbox folder.
So if you don't want to store the image as a blob file in the database, you should save the image in the caches folder inside your App's documents folder and then store the filename you set to the image in the database.
Since all images are going to be in the same path folder, you don't need to actually save the entire path in the database, but only the filename should be sufficient enough.
I'm trying to copy a downloaded file to a specific folder in the app's documents directory but can't seem to get it working. The code I'm using is:
NSString *itemPathString = #"http://pathToFolder/folder/myFile.doc";
NSURL *myUrl = [NSURL URLWithString:itemPathString];
NSArray *paths = [fm URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask];
NSURL *folderPath = [[paths objectAtIndex:0] URLByAppendingPathComponent:#"folder"];
NSURL *itemURL = [documentsPath URLByAppendingPathComponent:#"myFile.doc"];
// copy to documents directory asynchronously
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
NSFileManager *theFM = [[NSFileManager alloc] init];
NSError *error;
[theFM copyItemAtURL:myUrl toURL:itemURL error:&error];
}
});
I can retrieve the file OK but can't copy it. Can anyone tell me if there's anything wrong with the above code?
If downloading a file from a server, if it's a reasonably small file (e.g. measured in kb, not mb), you can use dataWithContentsOfURL. You can use that method to load the file into memory, and then use the NSData instance method writeToFile to save the file.
But, if it's a larger file, you will want to use NSURLConnection, which doesn't try to hold the whole file in memory, but rather writes it to the file system when appropriate. The trick here, though, is if you want to download multiple files, you either have to download them sequentially, or encapsulate the NSURLConnection and the NSOutputStream such that you can have separate copies of those for each simultaneous download.
I have uploaded a project, Download Manager that demonstrates what a NSURLConnection implementation might look like, but it's non-trivial. You might rather want to contemplate using an established, third-party library, such as ASIHTTPRequest or RestKit.
If you want to access a folder with a given name you should check if it exists and if not create it. That could quite easy be done like this:
NSString *folder = [documentsPath stringByAppendingPathComponent:folderName];
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error = nil;
if (![fileManager fileExistsAtPath:folder]) {
[fileManager createDirectoryAtPath:folder withIntermediateDirectories:YES attributes:nil error:&error];
}
if (error != nil) {
NSLog(#"Some error: %#", error);
return;
}
EDIT
If you want to check if the folder was created properly on your device got to Organizer -> Devices -> [YourDevelopingDeviceWhereTheAppWasInstalled] -> Applications -> [YourApplication]
In the lower section you should at least see some folders like Documents. And if successful your created folders as well.
You need to create any intermediate directories prior to copying files. Check in the Simulator folder to see wether the "folder" directory is created in the applications Documents-folder.
Path to simulator is /Users/$username/Library/Application Support/iPhone Simulator/
I have a UIViewController with an UIWebView which displays a pdf file depending which row was clicked before in an UITableView. Now I want to add a button for the user to save this pdf file locally for offline use.
Then there is a second UITableView which should display the name of the saved pdf and by clicking on it another UIViewController appears and displays the saved pdf on a UIWebView offline.
What would be a good way to start?
Thanks
You can try this way:
1) Add a button to the View containing UIWebView
2) At button press save the file shown in UIWebView
(note: in iOS 5 you must save data that can be easily recreated or downloaded to the caches directory)
- (IBAction)buttonPress:(id)sender
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
NSString *cachePath = [paths objectAtIndex:0];
BOOL isDir = NO;
NSError *error;
//You must check if this directory exist every time
if (! [[NSFileManager defaultManager] fileExistsAtPath:cachePath isDirectory:&isDir] && isDir == NO)
{
[[NSFileManager defaultManager] createDirectoryAtPath:cachePath withIntermediateDirectories:NO attributes:nil error:&error];
}
NSString *filePath = [cachePath stringByAppendingPathComponent:#"someName.pdf"]
//webView.request.URL contains current URL of UIWebView, don't forget to set outlet for it
NSData *pdfFile = [NSData dataWithContentsOfURL:webView.request.URL];
[pdfFile writeToFile:filePath atomically:YES];
}
3) On application start you need to check what files are stored (iOS can delete cache directory if there is not enough space on iPhone)