I am using the NSMetaDataQuery to search for iCloud documents, as recommended, but it's also searching sub-directories. Is there any way to have it search only the root directory? My code at the moment is...
NSMetadataQuery *query = [[NSMetadataQuery alloc] init];
_query = query;
[query setSearchScopes:[NSArray arrayWithObject:
NSMetadataQueryUbiquitousDocumentsScope]];
NSPredicate *pred = [NSPredicate predicateWithFormat:
#"%K == %#", NSMetadataItemFSNameKey, optionsFilename];
Thanks!
Ray
I hope it isn't too late for my answer...
I have the same issue but after a while I found a way to get this done: Compare resource URL without last path component against desired directory path.
NSPredicate(format: "%K.URLByDeletingLastPathComponent.path == %#", argumentArray: [NSMetadataItemURLKey, iCloudDocsURL.path])
This predicate works like a charm!
Cheers
Related
I retrieved a NSURL from a NSSavePanel. I now have this NSURL which gives me the following:
file://localhost/Users/brett/Documents/asdf%20asdf.json
Now, it is easy for me to retrieve just the filename using something like the following:
[[[NSFileManager defaultManager] displayNameAtPath:pathAndFilename] stringByDeletingPathExtension]
This gives me just the localized filename, as expected: asdf%20asdf
So, how do I get the path, like so: file://localhost/Users/brett/Documents/
-[NSURL URLByDeletingLastPathComponent] is the simplest way to achieve this.
You could use NSString methods to work with file paths. For example,
NSString *directory = [[URL absoluteString] stringByDeletingLastPathComponent];
NSString *filename = [[URL absoluteString] lastPathComponent];
You could find other useful methods in Apple Docs: NSString Class Reference -> Working with Paths section
Directly from your NSSavePanel:
NSSavePanel *savePanel;
...
NSString *path = savePanel.directoryURL.path;
I have a subclass of the CoreDataTableViewController (subclass of UITAbleViewController dome by the people on Stanford done to link CoreData and TableViews). On this Class, I want to perform a fecth, sorting by an attribute called "definition" and the code which executes it is the following:
- (void)setupFetchedResultsController{
NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:self.entity];
request.propertiesToFetch=[NSArray arrayWithObject:#"definition"];
request.returnsDistinctResults=YES;
NSPredicate *predicate1 = [NSPredicate predicateWithFormat:#"%K != nil", #"definition"];
NSPredicate *predicate2 = [NSPredicate predicateWithFormat:#"%K != ''", #"definition"];
NSPredicate *predicate3= [NSPredicate predicateWithFormat:#"%K contains[cd] %#", #"definition", self.seachBar.text];
NSArray *prepredicateArray;
if ([self.seachBar.text length]) {
prepredicateArray = [NSArray arrayWithObjects:predicate1, predicate2, predicate3,nil];
}else {
prepredicateArray = [NSArray arrayWithObjects:predicate1, predicate2,nil];
}
request.predicate=[NSCompoundPredicate andPredicateWithSubpredicates:prepredicateArray];
request.sortDescriptors = [NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:#"definition" ascending:YES ]];
self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request
managedObjectContext:self.managedObjectContext
sectionNameKeyPath:nil
cacheName:nil];
[self performFetch];
}
If I understood it correctly, setting request.returnsDistinctResults=YES; should avoid fetching duplicates. However it doesn't work and I'm seeing duplicates of this attribute's value.
Is there something I'm missing there? I'd appreciate some pointings there. Thank you in advance.
EDIT: If anyone is having the same issue here, after applying David's answer the resulting fetchedResultsController is just a NSDIctionary with object with only the requested value, which for displaying only purposes is quite fine. One thing I've done in cellForRowAtIndexPath in order to display the results on the cell label is:
Before:
HNMR *hnmr = [self.fetchedResultsController objectAtIndexPath:indexPath];
cell.textLabel.text=hnmr.definition;
After:
cell.textLabel.text=[[self.fetchedResultsController objectAtIndexPath:indexPath] valueForKey:#"definition"];
From the documentation of returnsDistinctResults:
This value is only used if a value has been set for propertiesToFetch.
From the documentation of propertiesToFetch:
This value is only used if resultType is set to NSDictionaryResultType.
From the documentation of resultType:
The default value is NSManagedObjectResultType.
This all tells me that the propertiesToFetch is ignored because you haven't set the resultType yourself and the default it to return managed objects instead of dictionaries. Since the propertiesToFetch is ignored the returnsDistinctResults is ignored as well and thus you are still getting duplicates.
Try setting the result type to return dictionaries instead of managed objects.
request.resultType = NSDictionaryResultType;
In addition to David Rönnqvist answer I suggest a useful link (with a sample) on selecting distinct values with Core Data:
core-data-how-to-do-a-select-distinct
Hope that helps.
i have big pool of core date objects (around 10000) and there is too long time doing code according profile:
NSDate *maxExternalChangedDate = [codes valueForKeyPath:#"#max.externalChangedDate"];
is community know better way to found it?
NSString *rateSheetID = [rateSheetAndPrefix valueForKey:#"rateSheetID"];
NSFetchRequest *requestCodesForSale = [[NSFetchRequest alloc] init];
[requestCodesForSale setEntity:[NSEntityDescription entityForName:#"CodesvsDestinationsList"
inManagedObjectContext:self.moc]];
[requestCodesForSale setPredicate:[NSPredicate predicateWithFormat:#"(%K.carrier.GUID == %#)",relationshipName,carrierGUID]];
NSError *error = nil;
NSArray *codes = [self.moc executeFetchRequest:requestCodesForSale error:&error];
if (error) NSLog(#"Failed to executeFetchRequest to data store: %# in function:%#", [error localizedDescription],NSStringFromSelector(_cmd));
NSNumber *count = [codes valueForKeyPath:#"#count.externalChangedDate"];
if (count == 0) {
[requestCodesForSale release];
[pool drain], pool = nil;
return YES;
}
NSDate *maxExternalChangedDate = [codes valueForKeyPath:#"#max.externalChangedDate"];
By using NSFetchRequest and returning NSDictionaryResultType You can use NSExpressionDescription to yeild the results for functions like max() and min().
Sample Code from Apple
NSExpression *keyPathExpression = [NSExpression expressionForKeyPath:#"salary"];
NSExpression *maxSalaryExpression = [NSExpression expressionForFunction:#"max:"
arguments:[NSArray arrayWithObject:keyPathExpression]];
NSExpressionDescription *expressionDescription = [[NSExpressionDescription alloc] init];
[expressionDescription setName:#"maxSalary"];
[expressionDescription setExpression:maxSalaryExpression];
[expressionDescription setExpressionResultType:NSDecimalAttributeType];
[request setPropertiesToFetch:[NSArray arrayWithObject:expressionDescription]];
Check out this doc for more information.
Core Data Programming Guide
I have the same issue.
In theory this should work, but for me it did not.
For some reasons the query crashes with the error that the database is corrupt.
In the end I perfomed a query, where I ordered on my field DESCENDING, and using setFetchLim it:1. Its not perfect, but at least it worked.
Also I made sure the field I use has an index.
Since I have few records, this works fine.
On 30000 records, it might be a problem though.
I followed the IOS documentation, fot fatch a "max:" query, but only got "database corrupted" errors. That is the sample code from Apple fails BADLY.
Googling the internet, it seem the call to setPropertiesToFetch fails in IOS 5+ ??!
I have not found any way around that.
Using a normal query, it worked without any issue.
So I must conclude Apple code is no longer corerct.
I'm trying to read ~/Library/Preferences/com.apple.mail.plist (on Snow Leopard) to get the email address and other information to enter into the about dialog. I'm using the following code, which is obviously wrong:
NSBundle* bundle;
bundle = [NSBundle mainBundle];
NSString *plistPath = [bundle pathForResource:#"~/Library/Preferences/com.apple.mail.plist" ofType:#"plist"];
NSDictionary *plistData = [NSDictionary dictionaryWithContentsOfFile:plistPath];
NSString *item = [plistData valueForKeyPath:#"MailAccounts.Item 2.AccountName"];
NSLog(#"Result = %#", item);
Moreover, the value I need to read is MailAcounts -> Item 2 -> AccountName and I am not sure I am doing this correctly (due to the space in the Item 2 key).
I tried reading Apple's developer guide to plist files but no help there.
How can I read a plist and extract the values as an NSString?
Thanks.
The first level is an array, so you need to use "MailAccounts.AccountName" and treat it as NSArray*:
NSString *plistPath = [#"~/Library/Preferences/com.apple.mail.plist" stringByExpandingTildeInPath];
NSDictionary *plistData = [NSDictionary dictionaryWithContentsOfFile:plistPath];
NSArray *item = [plistData valueForKeyPath:#"MailAccounts.AccountName"];
NSLog(#"Account: %#", [item objectAtIndex:2]);
Alternatively you can go by keys and pull the array from "MailAccounts" first using valueForKey: (which will yield NSArray*) and then objectAtIndex: to get the dictionary of that particular account (useful if you need more than the name).
Two things:
You don't want or need to use NSBundle to get the path to the file. The file lies outside of the app bundle. So you should just have
NSString *plistPath = #"~/Library/Preferences/com.apple.mail.plist";
You have to expand the tilde in the path to the user directory. NSString has a method for this. Use something like
NSString *plistPath = [#"~/Library/Preferences/com.apple.mail.plist" stringByExpandingTildeInPath];
Is there a manner to list all files (documents+data) I have in the iCloud (from a Mac) ?
I believe that the NSMetadataQuery object can help me with that, but is there any sample code out there ?
Thanks !
Here some sample code to do a query for txt files in your iCloud folder. If you want to look for other files, simple replace the predicate (NSPredicate *pred = [NSPredicate predicateWithFormat:#"%K ENDSWITH '.txt'", NSMetadataItemFSNameKey];).
To list all files, you could simply do #"NOT %K.pathExtension = '.'" but I'm not sure if this is the most elegant method. Suggestions welcome.
Have a look at this post to get the context and full code sample. Here is just the method to look for files.
-(void)loadDocument {
// (2) iCloud query: Looks if there are txt files in the cloud
NSMetadataQuery *query = [[NSMetadataQuery alloc] init];
_query = query;
//SCOPE
[query setSearchScopes:[NSArray arrayWithObject:NSMetadataQueryUbiquitousDocumentsScope]];
//PREDICATE
NSPredicate *pred = [NSPredicate predicateWithFormat:#"%K ENDSWITH '.txt'", NSMetadataItemFSNameKey];
[query setPredicate:pred];
//FINISHED?
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(queryDidFinishGathering:) name:NSMetadataQueryDidFinishGatheringNotification object:query];
[query startQuery];
}