I just make a file browser for iOS, I just need to know how to open any kind of file in a UIWebview. I think the webview can open any kind of file, that's because I chose to use a UIWebView to view the files directly in the app. Now my question.
How to programmatically switch to a UIViewController in the same UIStoryBoard and display the file? The file URL is stored in a string called path.
This is how fare I am, I just need to add the file viewer.
Can someone help me?
-(void) displayFile:(NSString*)fileName
{
NSError *error = nil;
NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
TO get the filename
NSString *folderPath = [documentsDirectory stringByAppendingPathComponent:fileName];
if (![[NSFileManager defaultManager] fileExistsAtPath:folderPath]) //Optionally check if folder already hasn't existed.
{
// do something
}
}
Hope this helps you...
Related
I am saving video/image in document directory.Now once the image is saved in document directory I want to save its reference in my local database.So I am thinking I can save URL of the image in the local database.
So is it constant throughout my app?
It's not constant, i have observed every time you launch the app it'll be different, but your data is moved to this new path. You can save your file name in your database, and dynamically append this file name to NSDocument directory.
- (NSString *)documentsFilePath:(NSString *)fileName {
NSArray *dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docsDir = [dirPaths firstObject];
NSString *filePath = [docsDir stringByAppendingPathComponent:fileName];
return filePath;
}
- (void)storeFile:(NSString *)fileName {
NSString *filePath = [self documentsFilePath:fileName];
// create if needed
if (![[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
// Write your data to file system here...
}
}
- (void)deleteFile:(NSString *)fileName {
NSString *filePath = [self documentsFilePath:fileName];
if ([[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
NSError *deleteErr = nil;
[[NSFileManager defaultManager] removeItemAtPath:filePath error:&deleteErr];
if (deleteErr) {
NSLog(#"Can't delete %#: %#", filePath, deleteErr);
}
}
}
Please handle nil checks and store only filename in DB
No, it's not constant. Whenever your app reinstall or updated on device the document directory will change, because when app installed on device os made an directory for app with some random id and each install this random it get changed by OS.
So, you need to make it dynamic own your own, like store the file name only and append the document directory path while using it.
I would suggest only saving the filename or subdirectory/filename (if you have a subdirectory) in the database and then only attaching that to the NSDocumentDirectory.
This will ensure that you always know where the file is...
NSDocumentDirectory is however consistent accross updates, so the files should remain in the document directory even if you update...
I want to open an email attachments(say .ppt, .doc, .xls .. etc files) through my iOS(iPad)app.
I am able to achieve the "Open In" on the mail attachments, my app opens up after that.
The handleOpenURL function will be called along with the url of the opened attachment.
Now in this function when i try to check for the file existence, it is not present.
NSFileManager *defaultManager = [NSFileManager defaultManager];
NSString *filePath = [NSString stringWithFormat:#"%#",url];
if ([defaultManager fileExistsAtPath:filePath]) {
NSLog(#"fileExists");
}else{
NSLog(#"file does not Exists");
}
What i want to achieve here is I want to copy the file through this url and paste it in some other folder.
But here the file itself doesn't exists.
Any help is highly appreciated.
That's not the proper way to convert an NSURL to a path. You should do:
NSString *filePath = [url path];
In my game, I'm saving stats of the player in a plist that I store in the Documents directory. I have an empty dictionary of each stats that should be saved named "Default_Stats.plist" so that if it's the first time the app is loaded, it will copy it in the appropriate directory so it could be loaded and overwritten at will. The problem is, every time my app is loaded, it doesn't recognize the "Stats.plist" and overwrite it with the Default Stats, resetting every stats the player have made... And weird enough, it was perfectly working on the simulator, but not on the device. Here's my code :
In this method I read the stats :
- (void) readStatsFromFile{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *statsPath = [[paths objectAtIndex:0] stringByAppendingPathComponent:#"Stats.plist"];
//Check if the file has already been created
if (![[NSFileManager defaultManager] fileExistsAtPath:statsPath]){
[self createStatsList];
}else{
stats = [[NSMutableDictionary dictionaryWithContentsOfFile:statsPath]retain];
}
}
Here's my creating method :
- (void) createStatsList{
NSString *statsPath = [[NSBundle mainBundle] bundlePath];
statsPath = [statsPath stringByAppendingPathComponent:#"Default_Stats.plist"];
stats = [[NSMutableDictionary dictionaryWithContentsOfFile:statsPath] retain];
[self writeStatsToFile];
}
And my writing method :
- (void) writeStatsToFile{
BOOL ok;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *statsPath = [[paths objectAtIndex:0] stringByAppendingPathComponent:#"Stats.plist"];
ok = [stats writeToFile:statsPath atomically:YES];
if (!ok) {
NSLog(#"Couldn't write to file");
}else
NSLog(#"Stats written succesfully!");
}
Please help, I really don't understand what's wrong! I hope I've made myself clear enough!
Use filepath instead of absolute path.
Maybe duplicates exist in your mac, which makes exists=true on simulator, but not on device.
The easiest way to check would be to NSLog the paths encountered. Refer to these tools - they allow console logs to be captured for release builds running on your device.
Most likely that your documents directory just doesn't exist - on the simulator you share a documents directory with everyone on the Mac; on the device everyone has his own directory. Use the file manager method
createDirectoryAtURL:url withIntermediateDirectories:YES
to make sure that the directory is there before you try writing there. (I tend to use the URL methods instead of the file path methods).
PS. I'd recommend having one method that returns the path or url that you want. It's a good habit not to duplicate your code again and again.
I would do pretty much that, like everything in one session:
gets the URL for the file in the Document folder;
if the file is not there yet, copies the file from bundle to the Documents folder;
that should be the method for that, I have defined some macros for avoiding mistyping the file's name in the code:
- (NSURL *)statsFileURL {
#define NSStringFromFileNameWithExtension(filename, extension) [(filename) stringByAppendingPathExtension:(extension)]
#define kExtension #"plist"
#define kDefaultStatsFileName #"Default_Stats"
#define kCustomStatsFileName #"Stats"
NSURL *_returnURL = nil;
NSFileManager *_fileManager = [NSFileManager defaultManager];
NSURL *_documentDirectory = [[_fileManager URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
NSURL *_myFileURLInDocumentFolder = [_documentDirectory URLByAppendingPathComponent:NSStringFromFileNameWithExtension(kDefaultStatsFileName, kExtension)];
if ([_fileManager fileExistsAtPath:[_myFileURLInDocumentFolder path]]) {
_returnURL = _myFileURLInDocumentFolder;
} else {
NSURL *_myFileURLInBundle = [[NSBundle mainBundle] URLForResource:kDefaultStatsFileName withExtension:kExtension];
if ([_fileManager fileExistsAtPath:[_myFileURLInBundle path]]) {
NSError *_error = nil;
if ([_fileManager copyItemAtURL:_myFileURLInBundle toURL:_myFileURLInDocumentFolder error:&_error]) {
if (_error == nil) {
_returnURL = _myFileURLInDocumentFolder;
} else {
// some error during copying
}
} else {
// some error during copying
}
} else {
// the file does not esixts at all, not even in the bundle
}
}
return _returnURL;
}
the URL always points inside the Documents folder, so you will have read/write access to the file – or will be nil if some error happens.
after you have the URL, you can restore back to file without any issue, and at some other point in runtime you can override the file for your convenience anytime.
NOTE: you may need to extend this code for a more detailed error handling, I put the comment only the places when you need to worry about potential errors.
I am donwloading and retrieving files with ASIHTTPRequest. It already works, but now I am trying to break the download, when it is already stored. I can't figure out, how to implement this problem. I would like to solve it with an if-clause: if the file is not cached, download it else break. Would you mind to help me writing a proper Objective-C code? I have the file path, if I need it so compare or look after that file.
Thanks in advance!
pseudo code :
-(IBAction) download : (id) sender {
if (data1.pdf) {
// the download algorithm
}
else
break;
}
If you mean how you can check if a file is stored in the documents directory of your device, then you can use:
NSString* documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString* file = [documentsPath stringByAppendingPathComponent:#"data.pdf"];
if ([[NSFileManager defaultManager] fileExistsAtPath:file]) {
...
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)