The two problems: Loading the plist into an NSDictionary: This is a simple problem, which it seems you have already figured out. The global object in your plist is an array, not a dict, so when you load it into the dictionary, it doesn’t know what to do (incompatable types), so you’re getting an empty … Read more
To write in file NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; NSString *filePath = [documentsDirectory stringByAppendingPathComponent:FILE_NAME]; [myArray writeToFile:filePath atomically:YES]; To read from file NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; NSString *filePath = [documentsDirectory stringByAppendingPathComponent:FILE_NAME]; myArray = [NSArray arrayWithContentsOfFile:filePath]; myArray will be nil if file is not … Read more
for (NSString* key in xyz) { id value = xyz[key]; // do stuff } This works for every class that conforms to the NSFastEnumeration protocol (available on 10.5+ and iOS), though NSDictionary is one of the few collections which lets you enumerate keys instead of values. I suggest you read about fast enumeration in the … Read more
Finally we can solve this problem easily using JSONModel. This is the best method so far. JSONModel is a library that generically serialize/deserialize your object based on Class. You can even use non-nsobject based for property like int, short and float. It can also cater nested-complex JSON. Considering this JSON example: { “accounting” : [{ … Read more
No, they are not ordered. As long as you don’t add or remove any elements from the dictionary, they will remain in the same order, but as soon as you add or remove an element, the new order will be completely different. If you need the keys/values to be ordered, use an NSArray (or some … Read more
As of Swift 4 you can create a dictionary directly from a sequence of key/value pairs: let keys = [“one”, “two”, “three”] let values = [1, 2, 3] let dict = Dictionary(uniqueKeysWithValues: zip(keys, values)) print(dict) // [“one”: 1, “three”: 3, “two”: 2] This assumes that all keys are different, otherwise it will abort with a … Read more
A couple of years ago, I wrote a few category methods for exactly the same reason, transforming a whole tree of user defaults to mutable. Here they are – use them at your own risk! 🙂 // // SPDeepCopy.h // // Created by Sherm Pendley on 3/15/09. // #import <Cocoa/Cocoa.h> // Deep -copy and -mutableCopy … Read more
NSDictionary and the other collection classes are actually class clusters: several concrete subclasses classes masquerading under the interface of a single class: they all provide the same functionality (because they are subclasses of the same class — in NSDictionary’s case, this involves the three “primitive methods” -count, -objectForKey:, and -keyEnumerator), but have different internal workings … Read more
I’ve made a few changes to Jacob’s original answer to extend it to handle dictionaries and arrays stored within the original dictionary. #import “NSDictionary+NullReplacement.h” #import “NSArray+NullReplacement.h” @implementation NSDictionary (NullReplacement) – (NSDictionary *)dictionaryByReplacingNullsWithBlanks { const NSMutableDictionary *replaced = [self mutableCopy]; const id nul = [NSNull null]; const NSString *blank = @””; for (NSString *key in self) … Read more
You’re using NSDictionary. Unless you explicitly need it to be that type for some reason, I recommend using a Swift dictionary. You can pass a Swift dictionary to any function expecting NSDictionary without any extra work, because Dictionary<> and NSDictionary seamlessly bridge to each other. The advantage of the native Swift way is that the … Read more