I have an NSMutableArray called myMutbaleArray that looks like this when I log it
2015-12-08 17:04:21.679 APP[3342:573379] (
{
id = 19;
"num_test" = 100000;
url = "http://fsad.com";
},
{
id = 20;
"num_test" = 100001;
url = "http://teeeet.com";
}
)
And I want to add an object that looks like this
{
id = 21;
"num" = 100002;
url = "http://example.com";
}
So I am trying this
[myMutbaleArray addObject:#{ #"id":#"23",#"num_test":#"100000", #"url":mainDict[#"website_url"],#"website_name":#"website"}];
But when I do this I get
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[__NSCFArray insertObject:atIndex:]: mutating method sent to immutable object'
I initialize the array like this
#interface {
NSMutableArray *socailArray;
}
//inside connectionDidFinishLoading
socailArray = [dataDict valueForKey:#"socail"];
Why can I add another dictionary to the MutableArray?
Thanks
If you see this, your array is actually not a mutable array. Here is the hint:
-[__NSCFArray insertObject:atIndex:]
^^^^^^^^^^^
The object is of type __NSCFArray, which is an internal counterpart of NSArray.
Even if you declare your variable as NSMutableArray the pointer can point to an object of any type (event for example NSRegularExpression). Important is, how it is created.
This happens to most people if they serialise an array either using NSUserDefaults, NSJSONSerialization or what ever.
The key is to create a mutable copy when the array gets deserialised using
-[NSArray mutableCopy]
Note that this is not deep-copy. This means an array contained in the root array will not be mutable copied and needs to be replaced separately.
Deep copying can be achieved using this:
// array
NSArray *originalArray = #[#"a", #"b", #[#1, #2]];
NSMutableArray *mutableArray = (NSMutableArray *)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, (CFArrayRef)originalArray, kCFPropertyListMutableContainers);
// dictionary
NSDictionary *originalDictionary = #{#"a": #"b", #"c": #[#{#"abc": #123}]};
NSMutableDictionary *mutableDictionary = (NSMutableDictionary *)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, (CFDictionaryRef)originalDictionary, kCFPropertyListMutableContainers);
You should change init to:
//inside connectionDidFinishLoading
socailArray = [NSMutableArray arrayWithArray:[dataDict valueForKey:#"socail"]];
Because: [dataDict valueForKey:#"socail"] is a NSArray.
With socailArray = [dataDict valueForKey:#"socail"];, the type of [dataDict valueForKey:#"socail"] is NSArray, so it auto cast socailArray into NSArray, that's why you can not insert thing into this.
To avoid this, you must be hold socailArray as NSMutableArray using:
socailArray = [[dataDict valueForKey:#"socail"] mutableCopy];
Hope this could help.
Related
I've looked at lots of questions about NS(Mutable)Arrays. I guess I am not grokking the concept, or the questions don't seem relevant.
What I' trying to do is the following:
Incoming Array 1:
Name
Code
Start time
End Time
etc
Incoming Array 2
Code
Ordinal
What I want:
Ordinal
Name
Code
Start time
End Time
etc
This is my code at present:
int i=0;
for (i=0; i < stationListArray.count; i++) {
NSString *slCodeString = [stationListArray[i] valueForKey:#"Code"];
NSLog(#"slCodeString: %#", slCodeString);
int j=0;
for (j=0; j< lineSequenceArray.count; j++) {
NSString *lsCodeString = [lineSequenceArray[j]valueForKey:#"StationCode"];
NSLog(#"lsCodeString: %#", lsCodeString);
if ([slCodeString isEqualToString:lsCodeString]) {
NSLog(#"match");
NSString *ordinalString = [lineSequenceArray[j] valueForKey:#"SeqNum"];
NSLog(#"ordinalString: %#", ordinalString);
[stationListArray[i] addObject:ordinalString]; <------
}
}
}
I'm logging the values and they return correctly.
The compiler doesn't like the last statement. I get this error:
[__NSCFDictionary addObject:]: unrecognized selector sent to instance 0x7f9f63e13c30
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFDictionary addObject:]: unrecognized selector sent to instance 0x7f9f63e13c30'
Here is an excerpt from the StationListArray:
(
{
Address = {
City = Greenbelt;
State = MD;
Street = ".....";
Zip = 20740;
};
Code = E10;
Lat = "39.0111458605";
Lon = "-76.9110575731";
Name = Greenbelt;
}
)
NSString *ordinalString = [lineSequenceArray[j] valueForKey:#"SeqNum"]; //Is NSString
[stationListArray[i] addObject:ordinalString];//<----- trying to call addObject method of NSMutableArray on NSDictionary -> Not GOOD
When you do [stationListArray[i] you get NSDictionary in your case
(Generally it returns an NSObject that is inside the NSArray at the given index, in your case is NSDictionary).
So in order to complete your desired operation: you should make an NSMutableDictionary instance (In this case it should be the mutableCopy from the stationListArray[i]'s NSObject which is NSDictionary, when you do mutableCopy it copies the entire NSDictionary and makes it Mutable)
make the changes on it and then assign it in to the stationListArray[i]
For example:
NSMutableDictionary * tempDict = [[stationArray objectAtIndex:i]mutableCopy];//Create a mutable copy of the `NSDictionary` that is inside the `NSArray`
[[tempDict setObject:ordinalString forKey:#"Ordinal"]; //In this line you are adding the Ordinal `NSString` in to the tempDict `NSMutableDictionary` so now you have the desired `NSMutableDictionary`. You can change the key to whatever you wish.
[stationArray replaceObjectAtIndex:i withObject:[tempDict copy]];//Swap the original(old NSDictionary) with the new updated `NSMutableDictionary` I used the copy method in order to replace it with the IMMUTABLE `NSDictionary`
[stationListArray[i] addObject:ordinalString]; <------
This is not an NSMutableArray. You must use
[stationListArray addObject:ordinalString]; <------
instead of the what you have done.
Here is the way you can write a better understandable code because for me the code is not clear.You can also try like this in loop to achieve what you want.
NSMutableArray *array = [NSMutableArray new];
NSMutableDictionary *dictMain = [NSMutableDictionary new];
NSMutableDictionary *dictAddress = [NSMutableDictionary new];
[dictAddress setValue:#"Greenbelt" forKey:#"City"];
[dictAddress setValue:#"MD" forKey:#"State"];
[dictAddress setValue:#"....." forKey:#"Street"];
[dictAddress setValue:#"20740" forKey:#"Zip"];
[dictMain setValue:dictAddress forKey:#"Address"];
[dictMain setValue:#"E10" forKey:#"Code"];
[dictMain setValue:#"39.0111458605" forKey:#"Lat"];
[dictMain setValue:#"-76.9110575731" forKey:#"Lon"];
[dictMain setValue:#"Greenbelt" forKey:#"Name"];
[array addObject:dictMain];
I have an array inside a NSMutableDictionary and i want to add objects to it. With my current approach I get an error saying that the array is immutable.
I think the problem lies when I´m saving the dictionary to NSUserDefaults. I´m retrieving the is it a NSDictionary but I am at the same time creating a new NSMutableDictionary with the contents.
However, the array seems to be immutable. How do I replace an array inside of a dictionary?
My dictionary looks like this:
NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:[NSNumber numberWithInt:0], nil];
NSDictionary *dict = #{
#"firstKey": #{
#"theArray":array,
}
};
NSMutableDictionary *mutDict = [[NSMutableDictionary alloc] initWithDictionary:dict];
I am trying to add objects like this:
[[[mutDict objectForKey:#"firstKey"] objectForKey:#"theArray"] addObject:[NSNumber numberWithInt:5]];
I am able to add objects to the array inside mutDict before its saved to NSUserDefaults
The error message I get when I try to add to the array inside the dictionary after loading it from NSUserDefaults:
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[__NSCFArray insertObject:atIndex:]: mutating method sent to immutable object'
Here's what the documentation for dictionaryForKey: says on NSUserDefaults:
Special Considerations
The returned dictionary and its contents are immutable, even if the values you >originally set were mutable.
So when you retrieve your dictionary from NSUserDefaults the dictionary itself and all of the collections inside it are immutable. You can make the top level dictionary mutable (which I assume you are doing), but that won't propagate down into the now immutable NSArrays which are values in the dictionary.
The only way to get around this is to go through the dictionary that's returned and replace the immutable NSArrays with their mutable counterparts. It might look something like this.
- (NSMutableDictionary *)deepMutableCopyOfDictionary:(NSDictionary *)dictionary
{
NSMutableDictionary *mutableDictionary = [dictionary mutableCopy];
for (id key in [mutableDictionary allKeys]) {
id value = mutableDictionary[key];
if ([value isKindOfClass:[NSDictionary class]]) {
// If the value is a dictionary make it mutable and call recursively
mutableDictionary[key] = [self deepMutableCopyOfDictionary:dictionary[key]];
}
else if ([value isKindOfClass:[NSArray class]]) {
// If the value is an array, make it mutable
mutableDictionary[key] = [(NSArray *)value mutableCopy];
}
}
return mutableDictionary;
}
To be honest though it sounds like you're using NSUserDefaults for something a lot more complex then it is intended for. If you want to persist complex data structures then you should look into something like Core Data, or if that looks to be a bit overkill take a look at NSKeyedArchiver.
You can add object directly to the array:
NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:[NSNumber numberWithInt:0], nil];
NSDictionary *dict = #{
#"firstKey": #{
#"theArray":array,
}
};
NSMutableDictionary *mutDict = [[NSMutableDictionary alloc] initWithDictionary:dict];
//Since Objective-C objects are always passed by reference (using pointers) you can add object to the array
[array addObject:[NSNumber numberWithInt:55]];
Swift example of adding object to array which is part of a dictionary.
let arr = [0] // note that initial array may be immutable
var dict = ["fK": ["a":arr]] // even if "arr" will be mutable, but "dict" immutable
dict["fK"]!["a"]!.append(3) // this will not work. "dict" must be mutable
println(dict) //[fK: [a: [0, 3]]]
Another approach
var arr = [0] // initial array must be mutable
var dict = ["fK": ["a":arr]] // in both cases dictionary must be mutable
arr.append(3)
let newArr = arr
dict["fK"]!["a"]! = newArr // because we change it's content
println(dict) //[fK: [a: [0, 3]]]
as the title says I'm having an issue with taking objects out of an array, flipping them, and putting them back in. Below is the code I currently have that ends in this error
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayI removeObjectsAtIndexes:]: unrecognized selector sent to instance
I was wondering if anyone knew how to fix this? Here's a little more info on how I have it set up:
The object "PEG" is an NSString that displays "-0.6", "4.36"
GlobalSortedArray is an array filled with dictionary containing the PEG object
//Declare variables
NSMutableArray *negArray = [[NSMutableArray alloc]init];
NSMutableIndexSet *index = [[NSMutableIndexSet alloc]init];
int negcount = 0;
NSDictionary *forLoopDict;
for (forLoopDict in globalSortedArray)
{
if ([[forLoopDict objectForKey:#"PEG"] hasPrefix:#"-"])
{
[index addIndex:negcount];
}
negcount++;
}
NSLog(#"%#", negArray);
// Removes objects from main array. This is what seems to be messing up.
[globalSortedArray removeObjectsAtIndexes:index];
// Reverses the array
NSArray* reversedArray = [[negArray reverseObjectEnumerator] allObjects];
// insters them back into the main array
[globalSortedArray insertObjects:negArray atIndexes:0];
You are trying to remove an item from globalSortedArray. It is an NSArray and not mutable.
globalSortedArray as NSmutableArray
NSArray -- > NSMutableArray
I have the following code:
for (NSMutableDictionary *aDict in array)
{
// do stuff
[aDict setObject:myTitle forKey:#"title"];
}
My question is, if the array is filled with NSDictionary objects, will this for loop code as written automatically convert them into NSMutableDictionary objects?
Or do I need to do something more specific here to ensure that I don't get an unrecognized selector sent to instance error on setObject:forKey: in the loop?
Currently that will give you the error you mentioned. Whilst the loop is setup with mutable dictionaries, the underlying object is still immutable. You'd need to create a new dictionary out of it. Try this
NSMutableArray *newArray = [NSMutableArray array];
for (NSDictionary *aDict in array)
{
NSMutableDictionary *mutable = [aDict mutableCopy];
// do stuff
[mutable setObject:myTitle forKey:#"title"];
[newArray addObject:mutable];
}
No it will not automatically convert them. You have to do that yourself. You'll definitely get the unrecognized selector sent to instance exception.
Write an empty NSMutableArray to disk, then read it back, it becomes an immutable object.
But, if the NSMutableArray is not empty, it won't. How to explain that?
here are the codes:
NSMutableArray *testItems1 = [NSMutableArray array];
NSMutableDictionary *testList1 = [NSMutableDictionary dictionaryWithObjectsAndKeys:testItems1, #"list_items", #"list1", #"list_name", nil];
NSMutableArray *testItems2 = [NSMutableArray arrayWithObjects:#"item11", #"item22", nil];
NSMutableDictionary *testList2 = [NSMutableDictionary dictionaryWithObjectsAndKeys:testItems2, #"list_items", #"list2", #"list_name", nil];
NSMutableArray *testLists = [NSMutableArray arrayWithObjects:testList1, testList2, nil];
[testLists writeToFile:#"/tmp/testLists" atomically:YES];
NSMutableArray *testReadLists = [NSMutableArray array];
[testReadLists setArray:[NSArray arrayWithContentsOfFile:#"/tmp/testLists"]];
NSMutableDictionary *testReadList = [testReadLists objectAtIndex:0];
NSMutableArray *testReadItems = [testReadList objectForKey:#"list_items"];
[testReadItems addObject:#"item3"]; // Crashes here: "*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[__NSCFArray insertObject:atIndex:]: mutating method sent to immutable object'"
These two lines of code:
NSMutableArray *testReadLists = [NSMutableArray array];
[testReadLists setArray:[NSArray arrayWithContentsOfFile:#"/tmp/testLists"]];
give you a mutable array of immutable objects. You can add and remove objects from testReadLists but everything you get from this array (originally loaded from the plist) will be immutable.
Update - I was about to post info about the solution but the answer by Vivek describes what I was going to say.
Haven't tested this myself, but you probably want to first read the plist into an NSData, and then get the actual array by doing +[NSPropertyListSerialization propertyListWithData:options:format:error:], specifying NSPropertyListMutableContainers in the options argument (apple doc here)
Note this should give you a full hierarchy of mutable containers (an NSMutableArray containing NSMutableDictionaries, and so on). If all you want is an NSMutableArray at one particular level in the hierarchy, then the other posted solution/comments would probably be a more appropriate solution.
Objects read straight from property lists are always immutable. You might create a mutable object from them, but the objects themselves are immutable. These lines are the problem:
NSMutableDictionary *testReadList = [testReadLists objectAtIndex:0];
NSMutableArray *testReadItems = [testReadList objectForKey:#"list_items"];
testReadList is the first object in the mutable array testReadLists, but that object itself is still immutable despite the fact that the declared type of testReadList is NSMutable*. Likewise, the object you get back from the objectForKey: call is an instance of NSArray even though you're assigning it to testReadItems, which is declared as NSMutableArray*. You can avoid the problem by simply making a mutable copy before you add new items:
NSMutableArray *testReadItems = [[testReadList objectForKey:#"list_items"] mutableCopy];