Parsing a .csv file from a server with Objective-C - objective-c

I have looked for an answer of a long time and still not found one so I thought I'd ask the question myself.
In my iPad app, I need to have the capability of parsing a .csv file in order to populate a table. I am using http://michael.stapelberg.de/cCSVParse to parse the csv files. However, I have only been successful in parsing local files. I have been trying to access a file from a server but am getting nowhere.
Here is my code to parse a local .csv file:
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if (buttonIndex == 1)
{
//UITextField *reply = [alertView textFieldAtIndex:buttonIndex];
NSString *fileName = input.text;
NSLog(#"fileName %#", fileName);
CSVParser *parser = [CSVParser new];
if ([fileName length] != 0)
{
NSString *pathAsString = [[NSBundle mainBundle]pathForResource:fileName ofType:#"csv"];
NSLog(#"%#", pathAsString);
if (pathAsString != nil)
{
[parser openFile:pathAsString];
NSMutableArray *csvContent = [parser parseFile];
NSLog(#"%#", csvContent);
[parser closeFile];
NSMutableArray *heading = [csvContent objectAtIndex:0];
[csvContent removeObjectAtIndex:0];
NSLog(#"%#", heading);
AppDelegate *ap = [AppDelegate sharedAppDelegate];
NSManagedObjectContext *context = [ap managedObjectContext];
NSString *currentHeader = [heading objectAtIndex:0];
NSString *currentValueInfo = [heading objectAtIndex:1];
NSManagedObject *newObject = [NSEntityDescription insertNewObjectForEntityForName:#"Field" inManagedObjectContext:context];
[newObject setValue:#"MIS" forKey:#"header"];
[newObject setValue:currentHeader forKey:#"fieldName"];
for (NSArray *current in csvContent)
{
NSManagedObject *newField = [NSEntityDescription insertNewObjectForEntityForName:#"Field" inManagedObjectContext:context];
[newField setValue:currentHeader forKey:#"header"];
[newField setValue:currentValueInfo forKey:#"valueInfo"];
NSLog(#"%#", [current objectAtIndex:0]);
[newField setValue:[current objectAtIndex:0] forKey:#"fieldName"];
[newField setValue:[NSNumber numberWithDouble:[[current objectAtIndex:1] doubleValue]] forKey:#"value"];
}
NSError *error;
if (![context save:&error])
{
NSLog(#"Couldn't save: %#", [error localizedDescription]);
}
[self storeArray];
[self.tableView reloadData];
}
}
}
input.text = nil;
}
Forgive the weird beginning and ending brace indentation. :/
Anyway, so that is my code to take input from a user and access a file locally which I'm sure you guys have realized already. Now I want to know how to get the path of a file in my server.
Also if you guys see anything else wrong such as writing style and other bad habits please tell me as I'm new to iOS.
Thank you so much in advance! If you didn't understand my question please clarify as I'm bad at explaining myself at times! :)

As I am guessing you are trying to get data from a server's .csv file and want to show that data in table view list.
so I suggest you try to get that .csv file data in NSData and then work on that.
NSData *responseData = [NSData dataWithContentsOfURL:[NSURL URLWithString:#"serverUrl"]];
NSString *csvResponseString = [[[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding] autorelease];
NSLog(#"responseString--->%#",csvResponseString);
Now try to use nsstring's method (componentsSeparatedByString) with coma (')
arrSepratedData = [[responseString componentsSeparatedByString:#","];
Now use this arr for UITableView data populate.

Related

How to convert NSUrl to NSString?

After AVAssetExportSession has complete export video.
I have plan to garb Video Path to upload via Youtube.
but [GDataUtilities MIMETypeForFileAtPath:path defaultMIMEType:#"video/mp4"];
it only accept NSString.
Is it possible to convert NSUrl in to NSString for video file path.
i have try to use NSString *path = [ExportoutputURL absoluteString];
but it crash.
Here is the Code
- (void)exportDidFinish:(AVAssetExportSession*)session {
ExportoutputURL = session.outputURL;
_exporting = NO;
NSIndexPath *exportCellIndexPath = [NSIndexPath indexPathForRow:2 inSection:kProjectSection];
ExportCell *cell = (ExportCell*)[self.tableView cellForRowAtIndexPath:exportCellIndexPath];
cell.progressView.progress = 1.0;
[cell setProgressViewHidden:YES animated:YES];
[self updateCell:cell forRowAtIndexPath:exportCellIndexPath];
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
if ([library videoAtPathIsCompatibleWithSavedPhotosAlbum:ExportoutputURL]) {
[library writeVideoAtPathToSavedPhotosAlbum:ExportoutputURL
completionBlock:^(NSURL *assetURL, NSError *error){
dispatch_async(dispatch_get_main_queue(), ^{
if (error) {
NSLog(#"writeVideoToAssestsLibrary failed: %#", error);
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:[error localizedDescription]
message:[error localizedRecoverySuggestion]
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alertView show];
[alertView release];
}
else {
_showSavedVideoToAssestsLibrary = YES;
ExportCell *cell = (ExportCell*)[self.tableView cellForRowAtIndexPath:exportCellIndexPath];
[cell setDetailTextLabelHidden:NO animated:YES];
[self updateCell:cell forRowAtIndexPath:exportCellIndexPath];
NSArray *modes = [[[NSArray alloc] initWithObjects:NSDefaultRunLoopMode, UITrackingRunLoopMode, nil] autorelease];
[self performSelector:#selector(hideCameraRollText) withObject:nil afterDelay:5.0 inModes:modes];
}
});
}];
}
[library release];
}
- (void)uploadVideoFile {
NSString *devKey = DEVELOPER_KEY;
GDataServiceGoogleYouTube *service = [self youTubeService];
[service setYouTubeDeveloperKey:devKey];
NSURL *url = [GDataServiceGoogleYouTube youTubeUploadURLForUserID:kGDataServiceDefaultUser];
// load the file data
NSString *path = [ExportoutputURL absoluteString];//[[NSBundle mainBundle] pathForResource:#"video_2451" ofType:#"mp4"];//[mFilePathField stringValue];
NSFileHandle *fileHandle = [NSFileHandle fileHandleForReadingAtPath:path];
NSString *filename = [path lastPathComponent];
// gather all the metadata needed for the mediaGroup
NSString *titleStr = #"Upload Test";//[mTitleField stringValue];
GDataMediaTitle *title = [GDataMediaTitle textConstructWithString:titleStr];
NSString *categoryStr = #"Entertainment";//[[mCategoryPopup selectedItem] representedObject];
GDataMediaCategory *category = [GDataMediaCategory mediaCategoryWithString:categoryStr];
[category setScheme:kGDataSchemeYouTubeCategory];
NSString *descStr = #"GData Description";//[mDescriptionField stringValue];
GDataMediaDescription *desc = [GDataMediaDescription textConstructWithString:descStr];
NSString *keywordsStr = #"RAGOpoR Demo";//[mKeywordsField stringValue];
GDataMediaKeywords *keywords = [GDataMediaKeywords keywordsWithString:keywordsStr];
BOOL isPrivate = NO;//([mPrivateCheckbox state] == NSOnState);
GDataYouTubeMediaGroup *mediaGroup = [GDataYouTubeMediaGroup mediaGroup];
[mediaGroup setMediaTitle:title];
[mediaGroup setMediaDescription:desc];
[mediaGroup addMediaCategory:category];
[mediaGroup setMediaKeywords:keywords];
[mediaGroup setIsPrivate:isPrivate];
NSString *mimeType = [GDataUtilities MIMETypeForFileAtPath:path
defaultMIMEType:#"video/mp4"];
// create the upload entry with the mediaGroup and the file
GDataEntryYouTubeUpload *entry;
entry = [GDataEntryYouTubeUpload uploadEntryWithMediaGroup:mediaGroup
fileHandle:fileHandle
MIMEType:mimeType
slug:filename];
SEL progressSel = #selector(ticket:hasDeliveredByteCount:ofTotalByteCount:);
[service setServiceUploadProgressSelector:progressSel];
GDataServiceTicket *ticket;
ticket = [service fetchEntryByInsertingEntry:entry
forFeedURL:url
delegate:self
didFinishSelector:#selector(uploadTicket:finishedWithEntry:error:)];
[self setUploadTicket:ticket];
GTMHTTPUploadFetcher *uploadFetcher = (GTMHTTPUploadFetcher *)[ticket objectFetcher];
}
Error EXC_BAD_ACCESS at
NSString *path = [ExportoutputURL absoluteString];
Is it possible to convert NSUrl in to NSString for video file path.
Yes. Send it an absoluteString message.
i have try to use NSString *path = [ExportoutputURL absoluteString]; but it crash.
If you want a path, send the URL a path message. A string representing a URL is generally not a valid path; if you want a path, ask it for one.
As for the crash, it does not mean absoluteString is wrong. Sending absoluteString to an NSURL object is the correct way to get an NSString object that represents the URL. The problem is somewhere else.
Error EXC_BAD_ACCESS at
NSString *path = [ExportoutputURL absoluteString];
This probably means that ExportoutputURL points to something that is not nil but is also not a valid object. It might have pointed to an NSURL object at some point, but it doesn't now.
My guess would be that the problem is this:
ExportoutputURL = session.outputURL;
You assign the URL to the ExportoutputURL instance variable, but you don't retain the object or make your own copy. Therefore, you don't own this object, which means you are not keeping it alive. It may die at any time, most probably after this method (exportDidFinish:) returns.
The crash is because you call uploadVideoFile later, after the URL object has already died. You still have a pointer to it, but that object no longer exists, so sending a message to it—any message—causes a crash.
There are three simple solutions:
Retain the URL object when you assign it to your instance variable.
Make your own copy of the URL object and assign that to the instance variable.
Declare ExportoutputURL as a property, with either the strong keyword or the copy keyword, and assign the object to the property, not the instance variable. That will call the property's setter, which, if you synthesize it or implement it correctly, will retain or copy the URL for you.
Either way, you will own the object, and that will keep it alive until you release it. Accordingly, you will need to release it when you are done with it (in dealloc, if not earlier), so that you don't leak it.
This all assumes that you are not using ARC. If you are using Xcode 4.2 or later, and can require iOS 4 or later, you should migrate your project to ARC, as it makes so many things much simpler. You would not need to retain or copy this object if you were using ARC, which means that migrating to ARC now is a fourth solution (but certainly a larger-scale one).
Use either absolutePath or path as mentioned by Miek and Nepster. Expanding on their answers, the difference between lies in the prefix.
NSString* string1 = [url absoluteString]; // #"file:///Users/jackbrown/Music/song name.mp3"
NSString* string2 = [url path]; // #"/Users/jackbrown/Music/song name.mp3"`
NSString *path = [[NSString alloc] initWithString:[url path]]; ?
Use this. I think it will help you.
In Objective c
NSString *testString = testUrl.absoluteString;
In Swift
var testString : String = testUrl.absoluteString
Simply you can do it like this.
NSString *myString = [myURL absoluteString];

iOS/Objective-C: Attempting to Scan a string for substrings which will be assigned to multiple NSStrings

I'm attempting to complete the Stanford iPhone Programming (FA10) assignement "Flickr Fetcher" -- so far things are going well, however I have come to an impasse:
I have successfully extracted the location of the "Top 100" pictures, which are formated in a string as "Country, State, City". I would like to create two NSStrings -- one being the country, the other string being the State and City. From where I can then do
cell.textLabel.text = countryString;
cell.detailTextLabel.text = stateCityString;
in my table view datasource methods.
From research on stackoverflow and the Apple Documentaion, NSScanner seems to be my best bet -- here is what I have so far...
- (void)viewDidLoad {
//Get the top 100 photos from Flickr
self.topPlacesArray = [FlickrFetcher topPlaces];
NSString *mainLabelString = [[NSString alloc] init];
NSString *stringFromArray = [[NSString alloc] init];
//This retrieves the string of the location of each photo
stringFromArray = [topPlacesArray valueForKey:#"_content"];
NSScanner *theScanner = [NSScanner scannerWithString:stringFromArray];
NSCharacterSet *commaSet = [[NSCharacterSet alloc] init];
commaSet = [NSCharacterSet characterSetWithCharactersInString:#","];
while ([theScanner isAtEnd] == NO) {
if ([theScanner scanUpToCharactersFromSet:commaSet intoString:&stringFromArray]) {
NSLog(#"%#",stringFromArray);
}
}
I'm just trying to see if the string properly substrings itself -- however I am getting a "SIGBART" at the beggining of the while loop, the error is this:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayI length]: unrecognized selector sent to instance 0x8939eb0'
From all the documentation I have seen on NSScanner, it seems I have it set up properly, however, no matter what changes I do, it seems unable to even begin the loop.
What do I have to do to set up NSScanner properly, to avoid the "SIGABRT"? (for the record, i'm assuming "SIGABRT" is a segfault?). Thank you all for your time, you all are the best!
(Btw: I know this is not fully implemented yet for both country and state-city, i just want to get used to NSScanner, I will implement the rest once I get NSScanner under control)
EDIT 1: SosBorn! You are incredible! Thank you so much! So I have implemented this for my viewDidLoad:
- (void)viewDidLoad
{
self.topPlacesArray = [FlickrFetcher topPlaces];
NSArray *ArrayOfStrings = [[NSArray alloc] init];
NSArray *placeElements = [[NSArray alloc] init];
NSString *country = [[NSString alloc] init];
NSString *city = [[NSString alloc] init];
NSString *state = [[NSString alloc] init];
ArrayOfStrings = [topPlacesArray valueForKey:#"_content"];
for (NSString *place in ArrayOfStrings) {
placeElements = [place componentsSeparatedByString:#", "];
if ([placeElements count] == 3 && [placeElements objectAtIndex:0] != nil) {
city = [placeElements objectAtIndex:0];
[self.cityArray addObject:city];
state = [placeElements objectAtIndex:1];
[self.stateArray addObject:state];
country = [placeElements objectAtIndex:2];
[self.countryArray addObject:country];
NSLog(#"%#, %#, %#", city, state, country);
}
else {
NSLog(#"Did this work?");
}
}
[ArrayOfStrings release];
[placeElements release];
[country release];
[city release];
[state release];
[super viewDidLoad];
}
This worked like a complete charm BUT i'm having some bad access going on in the Delegate when trying to access self.window.rootViewController = self.viewController -- this doesn't make any-sense (i actually have a completely empty table, etc...) -- so i'm thinking I played with bad memory management with my substring-ing and now it gets in trouble with this delegate call.
Chuck, I was very interested in your comment as I was taught that the proper way to make variables is to call [myclass alloc] init]; and then release when you are done -- as I have. Of course my objective-C greenness is showing a bit... blush.
You all and this incredible community are such an asset to us Students -- thank you for all your time and dedication. The only path to progress is a path of cooperation!
EDIT 2: Ok -- now it's totally fixed with no terrible leaking problems. Chuck you were right! I had the pricniples of alloc init completely mixed up in my head -- here was my final solution:
NSMutableArray *array1 = [[NSMutableArray alloc] init];
NSMutableArray *array2 = [[NSMutableArray alloc] init];
NSMutableArray *array3 = [[NSMutableArray alloc] init];
self.cityArray = array1;
self.countryArray = array2;
self.stateArray = array3;
[array1 release];
[array2 release];
[array3 release];
NSArray *ArrayOfStrings = [topPlacesArray valueForKey:#"_content"];
NSArray *topPlaces = [NSArray arrayWithArray:ArrayOfStrings];
NSArray *topPlacesSorted = [topPlaces sortedArrayUsingSelector:#selector(compare:)];
ArrayOfStrings = topPlacesSorted;
for (NSString *place in ArrayOfStrings) {
NSArray *placeElements = [place componentsSeparatedByString:#", "];
if ([placeElements count] == 3 && [placeElements objectAtIndex:0] != nil) {
NSString *city = [placeElements objectAtIndex:0];
[self.cityArray addObject:city];
NSString *state = [placeElements objectAtIndex:1];
[self.stateArray addObject:state];
NSString *country = [placeElements objectAtIndex:2];
NSString *stateAndCountry = [NSString stringWithFormat:#"%#, %#", state, country];
[self.countryArray addObject:stateAndCountry];
NSLog(#"%#, %#, %#", city, state, country);
}
else {
NSLog(#"Nil Request");
}
Thank you again SosBorn, i was feeling like I had forgotten the basics of CS ಠ_ಠ.
The only thing that really bothers me is why do we have to initialize instance NSMutableArrays that way -- i found this was the only way to get them to actually work.
Not totally sure why it is crashing, but I think another approach to this would serve you better. You have a topPlacesArray, why not iterate through the array and process each array entry seperately? I am making some assumptions about the topPlacesArray, but it would look something like this:
for (NSString *place in topPlacesArray)
{
//Place is probably in this format: "Country, State, City"
NSArray *placeElements = [place componentsSeperatedByString:#","];
//This should give you an array with three elements. Country State and city.
NSString *country = [placeElements objectAtIndex:0];
NSString *cityState = [NSString stringWithFormat:#"%#, %#", country, cityState];
//Now you have your strings that you need. Do whatever you need to do with them.
//Add them to an array or set the value of a text label, etc.
}
Didn't take the time to handle memory management but you get the idea.

Adding Objects from an Array into Core Data

So, for the past two days or so I've been struggling with something that should honestly be a simple task. Here's a little introduction on what I'm trying to achieve.
What I'm doing is utilising a web service of my own, sending a request and parsing the returned JSON with SBJSON. What I know want to accomplish with this parsed JSON is to insert it into Core Data.
I have built a object model already which looks like the following:
#import <CoreData/CoreData.h>
#interface Event : NSManagedObject
{
}
#property (nonatomic, retain) NSString * summary;
#property (nonatomic, retain) NSString * content;
#property (nonatomic, retain) NSDate * updated;
#property (nonatomic, retain) NSString * title;
#property (nonatomic, retain) NSDate * created;
#property (nonatomic, retain) NSString * ID;
#end
These are all built in regards to what is being parsed, I think I may have to change the NSDate's to NSStrings at a later date, but for now they are NSDates.
So, now to show you what is being parsed. The JSON returns the following.
[{"note id":"525","note title":"Car","note summary":"","note content":"","note created":"1297130179","note_updated":"1297233954"},
{"note id":"252","note title":"Premium Users","note summary":"","note content":"","note created":"1296046367","note_updated":"1296699888"},
{"note id":"253","note title":"Welcome!","note summary":"","note content":"","note created":"1296046367","note_updated":"1296561871"}]
What I am wanting to do is create an entity "Event" and each entity stores the respective values for that event. Easy, right? Obviously not for me.
What I have tried...
NotaciousAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
NSManagedObjectContext *context = [appDelegate managedObjectContext];
NSManagedObject *newNote;
newNote = [NSEntityDescription insertNewObjectForEntityForName:#"Event" inManagedObjectContext:context];
[newNote setValue:[object valueForKey:#"note title"] forKey:#"title"];
[newNote setValue:[object valueForKey:#"note summary"] forKey:#"summary"];
[newNote setValue:[object valueForKey:#"note updated"] forKey:#"updated"];
NSError *error;
[context save:&error];
Yet this returns an error.
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Unacceptable type of value for attribute: property = "title"; desired type = NSString; given type = __NSArrayI; value = (
Car,
"Premium Users",
"Welcome!"
).'
Any ideas or code samples would help. I really need to get this fixed, all dependent on how this is being stored.
EDIT
Here's how we build the request and parse the string returned.
NSDictionary *params = [NSDictionary dictionaryWithObject:api_key forKey:#"api_key"];
[[LRResty client] get:#"http://notacio.us/api/note" parameters:params withBlock:^(LRRestyResponse *response){
if(response.status == 200) {
NSLog(#"Pulling the users notes \n%#", [response asString]);
// Create SBJSON object to parse JSON
SBJSON *parser = [[SBJSON alloc] init];
// parse the JSON string into an object - assuming [response asString] is a NSString of JSON data
NSDictionary *object = [parser objectWithString:[response asString] error:nil];
EDIT
Just thought I'd let people know that I'm currently using the Resty RESTful framework to make my calls to my own API. I thought this was the best alternative and easiest way for myself to build a wrapper for it. Here is the full request.
Resty documentation.
-(void)pullNotes {
NSDictionary *params = [NSDictionary dictionaryWithObject:api_key forKey:#"api_key"];
[[LRResty client] get:url parameters:params withBlock:^(LRRestyResponse *response){
if(response.status == 200) {
NSLog(#"Pulling the users notes \n%#", [response asString]);
// Create SBJSON object to parse JSON
SBJSON *parser = [[SBJSON alloc] init];
// parse the JSON string into an object - assuming [response asString] is a NSString of JSON data
NSDictionary *object = [parser objectWithString:[response asString] error:nil];
NotaciousAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
NSManagedObjectContext *context = [appDelegate managedObjectContext];
NSManagedObject *newNote;
newNote = [NSEntityDescription insertNewObjectForEntityForName:#"Event" inManagedObjectContext:context];
[newNote setValue:[object valueForKey:#"note title"] forKey:#"title"];
[newNote setValue:[object valueForKey:#"note summary"] forKey:#"summary"];
[newNote setValue:[object valueForKey:#"note updated"] forKey:#"updated"];
NSError *error;
[context save:&error];
}
if (response.status == 404) {
NSLog(#"FAIL\n%#", [response asString]);
}
}];
}
EDIT
So, now that I have fixed the JSON issue and am grabbing the individual strings and such from each array, I'm having issues storing the parsed strings into Core Data.
I'll show you what I currently have.
[newNote ] is the name given to the Core Data entity in the header file of the following.
-(void)pullNotes {
UIApplication *app = [UIApplication alloc];
app.networkActivityIndicatorVisible = YES;
NSDictionary *params = [NSDictionary dictionaryWithObject:api_key forKey:#"api_key"];
[[LRResty client] get:#"http://notacio.us/api/note" parameters:params withBlock:^(LRRestyResponse *response){
if(response.status == 200) {
NSLog(#"Pulling the users notes \n%#", [response asString]);
// Create SBJSON object to parse JSON
SBJSON *parser = [[SBJSON alloc] init];
// parse the JSON string into an object - assuming [response asString] is a NSString of JSON data
NSDictionary *object = [parser objectWithString:[response asString] error:nil];
NSArray *notes = [object valueForKey:#"result"];
for (NSDictionary *singleNote in notes){
// newNote.created = [singleNote objectForKey:#"note created"]; Need to work on parsing these properly...
// newNote.updated = [singleNote objectForKey:#"note updated"]; Need to work on parsing these properly...
NSString *notetitle = [singleNote objectForKey:#"note title"];
NSString *notesummary = [singleNote objectForKey:#"note summary"];
NSString *noteid = [singleNote objectForKey:#"note id"];
NSString *notecontent = [singleNote objectForKey:#"note content"];
// NSDate *createdDate =
// NSDate *updatedDate =
// If appropriate, configure the new managed object.
[newNote setValue:notetitle forKey:#"title"];
[newNote setValue:notesummary forKey:#"summary"];
[newNote setValue:noteid forKey:#"ID"];
[newNote setValue:notecontent forKey:#"content"];
NSLog(#"value is %#", notetitle);
NSError *error = nil;
if (![newNote.managedObjectContext save:&error]) {
/*
Replace this implementation with code to handle the error appropriately.
abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development. If it is not possible to recover from the error, display an alert panel that instructs the user to quit the application by pressing the Home button.
*/
NSLog(#"Unresolved error %#, %#", error, [error userInfo]);
abort();
}
[tableView reloadData];
app.networkActivityIndicatorVisible = NO;
}
}
if (response.status == 404) {
NSLog(#"FAIL\n%#", [response asString]);
app.networkActivityIndicatorVisible = NO;
}
}];
}
#end
However, running this code doesn't actually store the strings into the Core Data entity. As you can see it isn't finalised, a lot of commented code, but the basis is there. ANYWAY, I'm curious as to whether or not it is how I actually implement this in the pulling of the notes itself from the RootViewController...
In viewDidLoad() I'm calling the following...
ntIndex = [IndexNotes alloc];
ntIndex.api_key = api_key;
ntIndex.tableView = self.tableView;
[ntIndex pullNotes];
[ntIndex release];
[self.tableView reloadData];
}
Any help would be great, I'd love to hear what others think the issue is. I don't get any errors with the above code, just nothing is inserted into the Core Data and in turn isn't displayed in my UITableView in RootViewController...
The first thing I would do is log what this line returns:
[object valueForKey:#"note title"]
You'll find it's not the string you're expecting, but is an array of note titles.
eg:
NSLog(#"value is %#", [object valueForKey:#"note title"]);
Then you'll either need to fix your JSON or change the way you parse it.
Edit:
So when I say fix your JSON, I'm no expert, but I think it should look like this:
{"result":[{"note id":"525","note title":"Car","note summary":"","note content":"","note created":"1297130179","note_updated":"1297233954"}, {"note id":"252","note title":"Premium Users","note summary":"","note content":"","note created":"1296046367","note_updated":"1296699888"}, {"note id":"253","note title":"Welcome!","note summary":"","note content":"","note created":"1296046367","note_updated":"1296561871"}]}
Then:
NSDictionary *object = [parser objectWithString:[response asString] error:nil];
NSArray notes = [object valueForKey:#"result"];
for (NSDictionary *singleNote in notes){
[singleNote objectForKey:"note title"] //this gives you the title of the current note your on
}
It's to do with the fact [object valueForKey:#"note title"] is returning an array.
You'll like want to insert something more like [[object valueForKey:#"note title"] objectAtIndex:1] to take an object out of the array. However working out what index you want to insert from the title array is the hardest part.
Tim
EDIT:
Having looked into some others responses its apparent it's returning all the titles in one object. There's something either incredibly funky going on with your JSON. A way around this would be to possibly for loop over your results set from your JSON request and using the index from this loop to insert the correct title.
eg:
int count;
for (count = 0; count < [[object valueForKey:#"note title"] count]; count++)
{
// Do your other insert stuff here
[newNote setValue:[[object valueForKey:#"note title"] objectAtIndex:count] forKey:#"title"];
}
again this is just a dirty example of what you could possibly do so solve this problem.

Memory buildup when parsing XML into a Core Data store using NSXMLParser

I have a problem with an app that takes an XML feed, parses it, and stores the results into Core Data.
The problem only occurs on the very first run of the app when there is nothing in the store and the whole feed is parsed and stored.
The problem is simply that memory allocations build up and up until, on 50% of attempts it crashes the app, usually at around 10Mb.
The objects allocated seem to be CFData(store) objects and I can't seem to find any way to force a release of them.
If you can get it to run once and successfully complete the parsing and save to core data then every subsequent launch is fine, memory usage never exceeds 2.5Mb
Here's the general approach I have before we get into code:
Get the feed into an NSData object. Use NSFileManager to store it as a file.
Create a URL from the file path and give it to the parseXMLFile: method. Delegate is self.
On reaching parser:didStartElement:namespaceURI:qualifiedName:attributes: I create a dictionary to catch data from tags I need.
The parser:foundCharacters: method saves the contents of the tag to a string
The parser:didEndElement:... method then determines if the tag is something we need. If so it adds it to the dictionary if not it ignores it. Once it reaches the end of an item it calls a method to add it to the core data store.
From looking at sample code and other peoples postings here it seems there's nothing in the general approach thats wrong.
The code is below, it comes from a larger context of a view controller but I omitted anything not directly related.
In terms of things I have tried:
The feed is XML, no option to convert to JSON, sorry.
It's not the images being found and stored in the shared documents area.
Clues as to what it might be:
This is the entry I get from Instruments on the largest most numerous things allocated (256k per item):
Object Address Category Creation Time Live Size Responsible
Library Responsible Caller
1 0xd710000 CFData
(store) 16024774912 • 262144 CFNetwork URLConnectionClient::clientDidReceiveData(_CFData
const*,
URLConnectionClient::ClientConnectionEventQueue*)
And here's the code, edited for anonymity of the content ;)
-(void)parserDidStartDocument:(NSXMLParser *)feedParser { }
-(void)parserDidEndDocument:(NSXMLParser *)feedParser { }
-(void)parser:(NSXMLParser *)feedParser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qualifiedName attributes:(NSDictionary *)attributeDict
{
eachElement = elementName;
if ( [eachElement isEqualToString:#"item" ] )
{
//create a dictionary to store each item from the XML feed
self.currentItem = [[[NSMutableDictionary alloc] init] autorelease];
}
}
-(void)parser:(NSXMLParser *)feedParser foundCharacters:(NSString *)feedString
{
//Make sure that tag content doesn't line break unnecessarily
if (self.currentString == nil)
{
self.currentString = [[[NSMutableString alloc] init]autorelease];
}
[self.currentString appendString:feedString];
}
-(void)parser:(NSXMLParser *)feedParser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
eachElement = elementName;
NSString *tempString = [self.currentString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
if ( [eachElement isEqualToString:#"title"] )
{
//skip the intro title
if (![tempString isEqualToString:#"Andy Panda UK"])
{
//add item to di citonary output to console
[self.currentItem setValue:tempString forKey:eachElement];
}
}
if ( [eachElement isEqualToString:#"link"] )
{
//skip the intro link
if (![tempString isEqualToString:#"http://andypanda.co.uk/comic"])
{
//add item to dicitonary output to console
[self.currentItem setValue:tempString forKey:eachElement];
}
}
if ( [eachElement isEqualToString:#"pubDate"] )
{
//add item to dicitonary output to console
[self.currentItem setValue:tempString forKey:eachElement];
}
if ( [eachElement isEqualToString:#"description"] )
{
if ([tempString length] > 150)
{
//trims the string to just give us the link to the image file
NSRange firstPart = [tempString rangeOfString:#"src"];
NSString *firstString = [tempString substringFromIndex:firstPart.location+5];
NSString *secondString;
NSString *separatorString = #"\"";
NSScanner *aScanner = [NSScanner scannerWithString:firstString];
[aScanner scanUpToString:separatorString intoString:&secondString];
//trims the string further to give us just the credits
NSRange secondPart = [firstString rangeOfString:#"title="];
NSString *thirdString = [firstString substringFromIndex:secondPart.location+7];
thirdString = [thirdString substringToIndex:[thirdString length] - 12];
NSString *fourthString= [secondString substringFromIndex:35];
//add the items to the dictionary and output to console
[self.currentItem setValue:secondString forKey:#"imageURL"];
[self.currentItem setValue:thirdString forKey:#"credits"];
[self.currentItem setValue:fourthString forKey:#"imagePreviewURL"];
//safety sake set unneeded objects to nil before scope rules kick in to release them
firstString = nil;
secondString = nil;
thirdString = nil;
}
tempString = nil;
}
//close the feed and release all the little objects! Fly be free!
if ( [eachElement isEqualToString:#"item" ] )
{
//get the date sorted
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
formatter.dateFormat = #"EEE, dd MMM yyyy HH:mm:ss ZZZZ";
NSDate *pubDate = [formatter dateFromString:[currentItem valueForKey:#"pubDate"]];
[formatter release];
NSArray *fetchedArray = [[NSArray alloc] initWithArray:[fetchedResultsController fetchedObjects]];
//build the string to make the image
NSString *previewURL = [#"http://andypanda.co.uk/comic/comics-rss/" stringByAppendingString:[self.currentItem valueForKey:#"imagePreviewURL"]];
if ([fetchedArray count] == 0)
{
[self sendToCoreDataStoreWithDate:pubDate andPreview:previewURL];
}
else
{
int i, matches = 0;
for (i = 0; i < [fetchedArray count]; i++)
{
if ([[self.currentItem valueForKey:#"title"] isEqualToString:[[fetchedArray objectAtIndex:i] valueForKey:#"stripTitle"]])
{
matches++;
}
}
if (matches == 0)
{
[self sendToCoreDataStoreWithDate:pubDate andPreview:previewURL];
}
}
previewURL = nil;
[previewURL release];
[fetchedArray release];
}
self.currentString = nil;
}
- (void)sendToCoreDataStoreWithDate:(NSDate*)pubDate andPreview:(NSString*)previewURL {
NSManagedObjectContext *context = [fetchedResultsController managedObjectContext];
NSEntityDescription *entity = [[fetchedResultsController fetchRequest] entity];
newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context];
[newManagedObject setValue:[NSDate date] forKey:#"timeStamp"];
[newManagedObject setValue:[[currentItem valueForKey:#"title"] description] forKey:#"stripTitle"];
[newManagedObject setValue:[[currentItem valueForKey:#"credits"] description] forKey:#"stripCredits"];
[newManagedObject setValue:[[currentItem valueForKey:#"imageURL"] description] forKey:#"stripImgURL"];
[newManagedObject setValue:[[currentItem valueForKey:#"link"] description] forKey:#"stripURL"];
[newManagedObject setValue:pubDate forKey:#"stripPubDate"];
[newManagedObject setValue:#"NO" forKey:#"stripBookmark"];
//**THE NEW SYSTEM**
NSString *destinationPath = [(AndyPadAppDelegate *)[[UIApplication sharedApplication] delegate] applicationDocumentsDirectory];
NSString *guidPreview = [[NSProcessInfo processInfo] globallyUniqueString];
NSString *guidImage = [[NSProcessInfo processInfo] globallyUniqueString];
NSString *dpPreview = [destinationPath stringByAppendingPathComponent:guidPreview];
NSString *dpImage = [destinationPath stringByAppendingPathComponent:guidImage];
NSData *previewD = [NSData dataWithContentsOfURL:[NSURL URLWithString:previewURL]];
NSData *imageD = [NSData dataWithContentsOfURL:[NSURL URLWithString:[currentItem valueForKey:#"imageURL"]]];
//NSError *error = nil;
[[NSFileManager defaultManager] createFileAtPath:dpPreview contents:previewD attributes:nil];
[[NSFileManager defaultManager] createFileAtPath:dpImage contents:imageD attributes:nil];
//TODO: BETTER ERROR HANDLING WHEN COMPLETED APP
[newManagedObject setValue:dpPreview forKey:#"stripLocalPreviewPath"];
[newManagedObject setValue:dpImage forKey:#"stripLocalImagePath"];
[newManagedObject release];
before++;
[self.currentItem removeAllObjects];
self.currentItem = nil;
[self.currentItem release];
[xmlParserPool drain];
self.xmlParserPool = [[NSAutoreleasePool alloc] init];
}
[EDIT]
#Rog
I tried playing with NSOperation but no luck so far, the same me,ory build up with the same items, all about 256k each. Here's the code:
- (void)sendToCoreDataStoreWithDate:(NSDate*)pubDate andPreview:(NSString*)previewURL
{
NSManagedObjectContext *context = [fetchedResultsController managedObjectContext];
NSEntityDescription *entity = [[fetchedResultsController fetchRequest] entity];
newManagedObject = [NSEntityDescription insertNewObjectForEntityForName:[entity name] inManagedObjectContext:context];
[newManagedObject setValue:[NSDate date] forKey:#"timeStamp"];
[newManagedObject setValue:[[currentItem valueForKey:#"title"] description] forKey:#"stripTitle"];
[newManagedObject setValue:[[currentItem valueForKey:#"credits"] description] forKey:#"stripCredits"];
[newManagedObject setValue:[[currentItem valueForKey:#"imageURL"] description] forKey:#"stripImgURL"];
[newManagedObject setValue:[[currentItem valueForKey:#"link"] description] forKey:#"stripURL"];
[newManagedObject setValue:pubDate forKey:#"stripPubDate"];
[newManagedObject setValue:#"NO" forKey:#"stripBookmark"];
NSString *destinationPath = [(AndyPadAppDelegate *)[[UIApplication sharedApplication] delegate] applicationDocumentsDirectory];
NSString *guidPreview = [[NSProcessInfo processInfo] globallyUniqueString];
NSString *guidImage = [[NSProcessInfo processInfo] globallyUniqueString];
NSString *dpPreview = [destinationPath stringByAppendingPathComponent:guidPreview];
NSString *dpImage = [destinationPath stringByAppendingPathComponent:guidImage];
//Create an array and send the contents off to be dispatched to an operation queue
NSArray *previewArray = [NSArray arrayWithObjects:dpPreview, previewURL, nil];
NSOperation *prevOp = [self taskWithData:previewArray];
[prevOp start];
//Create an array and send the contents off to be dispatched to an operation queue
NSArray *imageArray = [NSArray arrayWithObjects:dpImage, [currentItem valueForKey:#"imageURL"], nil];
NSOperation *imagOp = [self taskWithData:imageArray];
[imagOp start];
[newManagedObject setValue:dpPreview forKey:#"stripLocalPreviewPath"];
[newManagedObject setValue:dpImage forKey:#"stripLocalImagePath"];
//[newManagedObject release]; **recommended by stackoverflow answer
before++;
[self.currentItem removeAllObjects];
self.currentItem = nil;
[self.currentItem release];
[xmlParserPool drain];
self.xmlParserPool = [[NSAutoreleasePool alloc] init];
}
- (NSOperation*)taskWithData:(id)data
{
NSInvocationOperation* theOp = [[[NSInvocationOperation alloc] initWithTarget:self
selector:#selector(threadedImageDownload:)
object:data] autorelease];
return theOp;
}
- (void)threadedImageDownload:(id)data
{
NSURL *urlFromArray1 = [NSURL URLWithString:[data objectAtIndex:1]];
NSString *stringFromArray0 = [NSString stringWithString:[data objectAtIndex:0]];
NSData *imageFile = [NSData dataWithContentsOfURL:urlFromArray1];
[[NSFileManager defaultManager] createFileAtPath:stringFromArray0
contents:imageFile
attributes:nil];
//-=====0jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjmn **OLEG**
}
You can disable the caching :
NSURLCache *sharedCache = [[NSURLCache alloc] initWithMemoryCapacity:0 diskCapacity:0 diskPath:nil];
[NSURLCache setSharedURLCache:sharedCache];
[sharedCache release];
Or clear it :
[[NSURLCache sharedURLCache] removeAllCachedResponses];
This should fix your problem.
Take a look at AQXMLParser. There is a example app that shows how to integrate it with Core Data on a background thread. It's a streaming parser so memory usage is minimal.
Set up a second MOC and fetched results controller for the UI and refetch when the parsing is complete to get the new data. (one option is to register for change notifications when the background MOC saves to merge between contexts)
For images, there are a number of third party categories on UIImageVew that support asynchronous downloads and placeholder images. So you would parse the image URL, store it in Core Data, then set the URL on the image view when that item is viewed. This way the user doesn't need to wait for all the images to be downloaded.
Your problem is here:
[newManagedObject release];
Get rid of it, and the crashes will be gone (you don't release NSManagedObjects, Coredata will handle that for you).
Cheers,
Rog

ObC : app crashes after returning NSMutableArray?

I am new to ObC and have a problem that i just cant fix. There may be other issues as well but the main issue is this:
Starting the app
Press button = load new view
In the new viewDidLoad i call another object/function and send a NSMutableArray
Process data and send back a NSMutableArray
App crash, see comment where. Most often when i go back and back again but sometimes the first time
As i am new to this i guess i do a lot of this wrong but could someone nice take a look at the code and give me some advice. I would assume i have problem with releasing something.
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(#" ");
NSLog(#"viewDidLoad ");
NSLog(#" ");
NSLog(#">>Processing prepareGame<<");
NSMutableArray *propArray1 = [[NSMutableArray alloc] initWithObjects:#"9999", nil]; //Init with dummy numbers
AccessPropertiesFile *readMyProperties = [AccessPropertiesFile new]; //Init function call to read file
NSLog(#"Prepare to call readProperties");
propArray1 = [readMyProperties readPropertiesFile:propArray1];
NSLog(#"Back from readProperties:error after this");
/*
for (NSString *element in propArray1) {
NSLog(#"Elements in prop2Array; %#", element);
}
*/
[readMyProperties release];
[propArray1 release];
}
-(NSMutableArray *)readPropertiesFile:(NSMutableArray *)readDataArray {
NSLog(#"Processing readProperties");
// For error information
NSError *error;
//Prepare File Manager
NSString *filePath = [self dataFilePath];
NSFileManager *fileMgr;
fileMgr = [NSFileManager defaultManager];
NSArray *propertiesArray = [NSArray alloc]; //Alloc array
//Check from what module the call is coming from to ecide what to do
if ([fileMgr fileExistsAtPath: filePath] == NO) {
NSLog (#"File not found");
//File does not exists, this is the first time the game starts
//Set up default parameters
NSString *fileString =#"0\n30\n30\n10\n1\n1\n1\n2\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n1\n";
// Write default parameters to file
[fileString writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:&error];
propertiesArray = [fileString componentsSeparatedByString:#"\n"]; // each line, adjust character for line endings
}
else { //File exists
NSLog (#"File exists");
NSString *fileString = [NSString stringWithContentsOfFile:filePath
encoding:NSUTF8StringEncoding error:nil]; // reads file into memory as an NSString
propertiesArray = [fileString componentsSeparatedByString:#"\n"]; // each line, adjust character for line endings
}
//Clean readDataArray
[readDataArray removeAllObjects];
//Populate return array
for (NSString *element in propertiesArray) {
//NSLog(#"Elements in propertiesArray; %#", element);
[readDataArray addObject:element];
}
NSLog(#"readDataArray: %#", readDataArray);
[propertiesArray release];
[readDataArray autorelease];
NSLog(#"returning from readProperties");
return readDataArray;
}
#end
You are over-releasing readDataArray (known as propArray1 in the method that didn't create it). You create it and autorelease it in your second method, then you release it again at the end of your first method (where it wasn't created).
I suggest you use Analyze feature that comes with latest XCode. It is a good feature that I always use to track if I forget to release or release too much.
I also spotted that you also over-release the propertiesArray because it contains the result from [fileString componentsSeparatedByString:], which will be autorelease according to Cocoa convention.