I have a NSDictionary loaded from a remote PList.
It contains an array of dictionaries:
(
{
id = "1234";
count = "45";
},
{
id = "244";
count = "89";
},
{
id = "9909";
count = "123";
}
)
How do I get this into an NSArray? I don't want separate arrays for each key.
I just want an NSArray of NSDictionary.
There is probably a simple answer, but this has been bugging me.
Thanks
You say you have a dictionary containing the array. Whatever the key for the array is, just ask do [dictionary objectForKey:theKey], and you'll have the array.
EDIT: From your comments, it sounds like you just have an NSArray which is not in an NSDictionary at all. If so, you already have what you are looking for.
How about:
NSArray *dicts = [NSPropertyListSerialization propertyListWithData:data
options:0
format:NSPropertyListOpenStepFormat
error:NULL];
Note that this is a deprecated plist format (XML or binary format is now preferred).
have u tried [dictionary objectAtIndex:0]objectAtIndex:0]. try iterating over objectAtIndex in the outer loop.
all the best.
Related
I have an NSMutableDictionary with a structure like:
Main Dictionary > Unknown Dictionary > Dictionaries 1,2,4,5,6...
My question is what is the best way to retrieve the Unknown Dictionary key and set it as a variable? This is what I've tried:
NSEnumerator *enumerator = [myMutableDict keyEnumerator];
id aKey = nil;
while ( (aKey = [enumerator nextObject]) != nil) {
id value = [myMutableDict objectForKey:aKey]; // changed to `aKey`
NSLog(#"%#: %#", aKey, value); // tip via rmaddy
}
What goes into objectForKey: if you don't know the name of the object in the key?
The other thought I had was to populate an NSArray, then pulling each of the keys out somehow.
for (NSString *object in myMutableDict)
myArray = [myArray arrayByAddingObject:MainDict];
}
If anyone can suggest a better way to get the object (unknown) from an NSMutableDictionary I'm interested to learn.
You can enumerate dictionaries like this:
NSDictionary * someDictionary = ... however you set your dictionary;
[someDictionary enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
NSLog(#"Key: %#", key);
NSLog(#"Object: %#", obj);
}];
and set:
*stop = YES;
when you find the object you're looking for.
I'm not entirely sure if I understand your question correctly. I assume you have a "main" dictionary with exactly one (unknown) key that maps to another dictionary, which you want to retrieve. This would be a simple and concise way to do this:
NSDictionary *unknownDictionary = mainDictionary[mainDictionary.allKeys.firstObject];
(Yes, some people won't like the dot syntax here, but I find it easier to read in this case. You might also want to add some error checking, for the case that mainDictionary is empty etc.)
I have NSArray of NSDictionaries I need to extract 2 values or remove the values I don't need from the dictionary in the example below I need to remove id and NumberValue. any of you knows how can I do that?
Array: (
{
customerUS= {
DisplayName = "level";
InternalName = "Number 2";
NumberValue = 1;
id = xwrf
},
customerCAN= {
DisplayName = "PurchaseAmount";
InternalName = "Number 1";
NumberValue = 3500;
id = adf;
};
}
)
I'll really appreciate your help.
First thing, You can not remove/insert/update value in (immutable) NSDictionary/NSArray you need to convert NSDictionary/NSArray to (mutable) NSMutableDictionary/NSMutableArray.
such like
NSArray *myArr = ....;
NSMutableArray *newMutableArr = [myArr mutableCopy];
Then you can change in newMutableArr.
Such like
for(int i = 0 ; i < newMutableArr.count ; i ++)
{
[[newMutableArr objectAtIndex:i] removeObjectForKey:#"id"];
[[newMutableArr objectAtIndex:i] removeObjectForKey:#"NumberValue"];
}
EDITED:
Without Use of for loop and removeObjectForKey, if you have array of dictionary and both are mutable then you can also delete a key and its object from all elements of the array like this:
[newMutableArr makeObjectsPerformSelector:#selector(removeObjectForKey:) withObject:#"id"];
[newMutableArr makeObjectsPerformSelector:#selector(removeObjectForKey:) withObject:#"NumberValue"];
I would advice you to read Apple documents.
For modifying any Collection object after it is created, you need the mutable version.
For NSDictionary we have NSMutableDictionary. Read here.
We have a method for removing objects:
- (void)removeObjectForKey:(id)aKey
There are other methods as well. You can easily refer them in the above mentioned documentation.
Find out removeObjectForKey for deleting record from NSMutabledictionary.
removeObjectForKey pass the key value whatever you have like
all this are your key
DisplayName,
InternalName,
NumberValue,
id
do like this
removeObjectForKey:#"id";
First of all you have to convert the array to mutable array and then you can remove the key-value pairs from dictionary.
NSMutableArray *mutableArray = [yourArray mutableCopy];for(int i=0;i<mutableArray.count;i++){ NSMutableDictionary *outerDictionary = [mutableArray objectAtIndex:i]; for(NSString *key in outerDictionary.allKeys){ NSMutableDictionary *innerDictionary = [outerDictionary objectForKey:key]; [innerDictionary removeObjectForKey:#"id"]; [innerDictionary removeObjectForKey:#"NumberValue"]; }
}
I am trying to parse this json and am not sure of parsing this because the keys like "vis-progress-control" might change and I am trying to build a general code which parses this type of a json. I am sure that "type" key will be present in the json structure.
NSDictionary *dict = [sData JSONValue];
NSArray *items = [dict valueForKeyPath:#"assets"];
NSLog(#"%#", items);
for (NSString *key in [[dict objectForKey:#"assets"]allKeys]) {
for (NSString *subKey in [[[dict objectForKey:#"assets"] objectForKey:key]allKeys]) {
NSLog(#"Value at subkey:%# is %#\n",subKey,[[[dict objectForKey:#"assets"]objectForKey:key]objectForKey:subKey]);
}
}
I am using the SBJson Library on Github. My actual issue is How do I access "direction", "degrees" etc when I do not know the "vjs-progress-holder" key?
I have also a widgets array nested within a widgets array. How do I get these values as well?
Read about tree traversal. Sounds like you want to traverse the "tree" of nodes and when you find a particular leaf value you will then traverse back up one level and know the parent is the container you want.
So the idea is that once it's parsed from the JSON, forget it's JSON because now it's just a tree in arrays and dictionaries. Traverse it by getting all the keys in the dictionary via allKeys (returns an array of keys) and then iterate through them getting the associated values (using something like (psuedo code):
for ( NSString * key in allkeysarray) {
NSString * val = [dict objectForKey: key];
if ( [val isEqualToString: #"gradient"] )
{
// now you know that this dictionary is the one you're looking for so you can maybe break out of this loop and just use the keys you know reference these values.
break;
}
}
hopefully that's enough to get you going.
Assuming I'm understanding your objective here, it seems like you want to do something like this?
NSDictionary *outerDict = [sData JSONValue];
NSDictionary *assets = outerDict[#"assets"];
for (NSDictionary *asset in [assets allValues]) {
NSString *type = asset[#"type"];
if ([type isEqualToString:#"gradient"]) {
float degrees = [asset[#"degrees"] floatValue];
// and read whatever other values you need for gradients
}
if ([type isEqualToString:#"image"]) {
// and read the appropriate values for images here...
}
}
So I'll make a different assumption here, which is that you want an array of gradients. So then that looks basically like this:
NSDictionary *outerDict = [sData JSONValue];
NSDictionary *assets = outerDict[#"assets"];
NSMutableArray *gradients = [NSMutableArray array];
for (NSDictionary *asset in [assets allValues]) {
NSString *type = asset[#"type"];
if ([type isEqualToString:#"gradient"]) {
// Add this asset to the list of gradients:
[gradients addObject:asset];
}
if ([type isEqualToString:#"image"]) {
// do something similar for images
}
}
Then, after having done that, if you would like to read the "degrees" field for the 4th gradient, for example, you will find it at gradients[3][#"degrees"]
I' m trying to iterate NSDictionary via the for in loop. But I want it to begin iteration from the end of this collection to its beginning. How can I implement this reversion?
NSDictionary is an unordered data structure. There is no concept of forward iteration, or backward iteration.
When you call NSDictionary in a foreach loop, you are iterating over an unordered list of keys. When Iterating an unordered list, the order is undefined, and thus so is reversing the order. It's akin to scattering a deck of cards on the floor, then asking someone to reverse the order.
Assuming there is some order hierarchy to your keys (numeric, alphabetical, etc), You can instead get the key collection, and sort it into a particular order, and then iterate the key collection, or reverse iterate that. However if this is an operation you are doing frequently, then I suspect that NSDictionary is not the best choice for a datastructure for your problem.
Mmm... the problem is that NSDictionary are unordered by nature.
So, a possible solution is make an NSArray with the keys, reverse that array with "reverseObjectEnumerator" and then make a loop over the array and use the keys on dictionary.
Something like this:
NSDictionary *_dict = [NSDictionary dictionaryWithObjectsAndKeys:
#"firstValue",#"firstKey",
#"secondValue",#"secondKey",
#"thirdValue",#"thirdKey",
nil];
NSArray *keysNormal = [_dict allKeys];
NSArray *keysReversed = [[[_dict allKeys] reverseObjectEnumerator] allObjects];
for(NSString *str in keysNormal)
{
NSLog(#"%#", [_dict objectForKey:str]);
}
for(NSString *str in keysReversed)
{
NSLog(#"%#", [_dict objectForKey:str]);
}
The log is:
thirdValue
secondValue
firstValue
firstValue
secondValue
thirdValue
NSArray * a = #[#"a",#"b",#"c"];
NSArray * b = [[a reverseObjectEnumerator] allObjects];
for (NSString * obj in b) {
NSLog(#"%#",obj);
}
Print c,b,a.
Try to reverse the keys of your dictionary like this:
NSArray * key = [[[dict allKeys] reverseObjectEnumerator] allObjects];
I have to check whether an NSMutableArray contains an object multiple times (for e.g. the array contains 1,2,3,1,4), I want to know how many times 1 is present in the array. I am aware of containsObject: but how to use it for this kind of check?
NSCountedSet may help as you want to track how many times a duplicate value occurs.
http://developer.apple.com/library/ios/#documentation/Cocoa/Reference/Foundation/Classes/NSCountedSet_Class/Reference/Reference.html#//apple_ref/occ/cl/NSCountedSet
A quick way would be to convert it to an NSSet and then back to an array. NSSets cannot contain duplicates. Alternatively copy the values one by one into a new array using a loop, and each time check that the new array does not contain a copy of the object before adding it.
It depends on your object types, but if they can be used as keys for an NSDictionary, I would create an NSMutableDictionary that points to NSNumber objects containing counts for each object instance. Something like:
NSArray *array = whatever;
NSMutableDictionary *d = [NSMutableDictionary dictionaryWithCapacity:array.count];
for ( id obj in array )
{
NSNumber *number = [d objectForKey:obj];
if ( number == nil )
{
[d setObject:[NSNumber numberWithInt:1] forKey:obj];
}
else
{
[d setObject:[NSNumber numberWithInt:([number intValue]+1) forKey:obj];
}
}
At the end of this code, you are left with an NSDictionary where the keys are your original objects and the values are NSNumbers that contain the number of times that key exists in the original.