I have a bug whereby an array of NSNumbers that is dynamically created is not producing the expected results. To see what is in the array, I have logged it out. I also manually created an equivalent array that does produce expected results and logged it out. The elements appear to be identical when logged but when I do an isEqualArray test they are different. Can anyone suggest a way to detect what is different so that I can fix it? Thanks for any suggestions.
Here is the code that logs out the arrays:
-(NSMutableDictionary *) getExistingContactsWithUIDs:(NSArray *)uids
{
int numElements = (int) uids.count;
NSLog(#"num elements in uids%d",numElements); //logs as 3
NSLog(#"first elementzzz%#zzz",uids[0]); //logs as zzz2101zzz
NSLog(#"2nd elementzzz%#zzz",uids[1]); //logs as zzz2098zzz
NSLog(#"3rd elementzzz%#zzz",uids[2]);//logs as zzz2100zzz
//Manually created array
NSArray*ualtids = #[#2101, #2098, #2100];
int numElementsAlt = (int) ualtids.count;
NSLog(#"num elements in uids%d",numElementsAlt); //logs as 3
NSLog(#"first alt elementzzz%#zzz",ualtids[0]);//logs as zzz2101zzz
NSLog(#"2nd alt elementzzz%#zzz",ualtids[1]);//logs as zzz2098zzz
NSLog(#"3rd alt elementzzz%#zzz",ualtids[2]);//logs as zzz2100zzz
//code to compare says they are different
if ([uids isEqualToArray:ualtids]) {
NSLog(#"Arrays same");
}
else{
NSLog(#"Arrays different ");
}
//Finally the code that creates the uids array is:
NSMutableArray *newUIDs = [NSMutableArray array];
for (i=0;i<max;i++)
{
uid = importContact.cid;
[newUIDs addObject:uid];
}
[Voice of ObiWan Kenobi:] Uuuuuuse the debugggerrrrr, Luuuuuuke!
The problem is that you are using the NSLog command. That calls description so you don't learn what the class of the NSArray's elements is. An NSNumber wrapping 1 and an NSString #"1" log exactly the same. So you learn nothing.
But if you will simply pause in the debugger at a breakpoint after the arrays are configured, you can examine them in the variables list, as shown here:
Those two arrays (arr1 and arr2) log the same, but in the variables list it is perfectly plain that one contains NSStrings and the other contains NSNumbers.
Related
I have an array, that consist of following strings:
[NSString stringByAppendingFormat:#"<p style=\"padding-left:20px;margin-bottom:-10px;\"><i>%#%#%#%#</i></p>",
wrappingBy, pack1, pack2, strFirmName];
For example, it have 200 different strings. First parameter - wrappingBy, may have several different names. For example - box, tube, bag, etc.
What i want is, to enumerate through that array, and create different arrays depending on that name. So, if my array consist of 50 strings start from box, 50 strings start from tube, and 100 strings start from bag i want 3 different arrays.
Is there any easy way to achieve that?
Try this:
Let's say you have the array of strings:
NSArray *arr=#[#"box3523sfgsg",#"boxsdfsdf3",#"bag!#$#",#"!##4bag",#"tube##$FR",#"tubeASAD"];
In your case, the above array is filled with following string
[NSString stringByAppendingFormat:#"<p style=\"padding-left:20px;margin-bottom:-10px;\"><i>%#%#%#%#</i></p>",
wrappingBy, pack1, pack2, strFirmName];
Now add the wrappingBy param to the array everytime you add the above string to the array, and make sure you don;t add duplicates to the array. YOu can check the duplicates before adding them to the array.
and in your case, you would do
NSMutableArray *arrayNAme=[[NSMutableArray alloc]init];
//make arrayName mutable
if (![arrayNAme containsObject: wrappingBy]) {
[arrayNAme addObject: wrappingBy];
}
you will get arrayNAMe contain following:
arrayNAme=#[#"box",#"bag",#"tube"];
Now search the main array string if it contains the wrapingBy names or not, if YES, add them to an array and add that array to the dicitonary:
NSMutableDictionary *myDictionary=[[NSMutableDictionary alloc]init];
for( NSString *nameString in arrayNAme) {
NSMutableArray *strnArray=[[NSMutableArray alloc]init];
for (NSString *str in arr)
{
if([str containsString:nameString])
{
[strnArray addObject:str];
[myDictionary setValue:strnArray forKey:nameString];
}
}
}
At the end you have the dictionary:
{
bag = (
"bag!#$#",
"!##4bag"
);
box = (
box3523sfgsg,
boxsdfsdf3
);
tube = (
"tube##$FR",
tubeASAD
);
}
Now you can get each key value and store them in a separate array.
Sorry guys, this problem I am running into is pretty trivial. I just can't wrap my head around it so hope someone can help me. Your help is really appreciated. I am getting JSON data through NSURLConnectDelegate with a web API. I get something like this back:
(
{
id = 340
name = Vicent },
{
id = 339
name = Johny },
{
id = 338
name = Eric }
)
and I save it in a NSMutableArray as a global variable. Now, I have a NSSet of "ids". For example:
{
340, 339
}
In the numberOfRowsInSection, I return the set's count. I am trying to load only the ids in the NSSet from the array with the data saved from the webAPI, so I do something like this in cellForRowIndexPath:
for (NSNumber *num in [set allObjects]) {
NSString *newString = [[savedArray objectAtIndex:indexPath.row]
NSString *new = [num stringValue];
if ([new isEqual:newString]) {
}}
How can I just populate the ids I want?
The JSON makes it look like you have an array of dictionaries, which is a reasonable data structure to use as the data source for a table view.
It sounds like you're trying to filter your array to only include the items that are in your set. Is that right?
If so, you could write code that would create a new array containing the subset of your array elements who's ID is also in your set. There are at least a half-dozen ways to do that. One fairly simple approach would be to use the NSArray method indexesOfObjectsPassingTest. You'd pass that method a block of code that would check each array element to see if it's id object was in your set.
That would give you an NSIndexSet with the indexes of the items in your array who's ID are in your set. Then you could use the NSArray method objectsAtIndexes to get an array of only the objects that are also in the set. Something like this (Assuming that your array of dictionaries is called savedArray and your set is called allObjects:
//get the indexes of items in the array savedArray who's id appears in the set allObjects
NSIndexSet *indexes = [savedArray indexesOfObjectsPassingTest:
^(NSDictionary *obj,
NSUInteger idx,
BOOL *stop)
{
return [allObjects member: obj[#"id"]] != nil;
}
];
//Now build an (immutable) array of just the objects who's ID are in the set
NSArray *subArray = [savedArray objectsAtIndexes: indexes];
The array subArray created above is immutable. If you need a mutable array you would need to make a mutable copy, which is a one-line change.
Disclaimer: I still struggle a little with block syntax, so the above might not be exactly correct, but it gives you the general idea.
I found this answer:
https://stackoverflow.com/a/5163334/1364174
Which presents how for in loop is implemented.
NSFastEnumerationState __enumState = {0};
id __objects[MAX_STACKBUFF_SIZE];
NSUInteger __count;
while ((__count = [myArray countByEnumeratingWithState:&__enumState objects:__objects count:MAX_STACKBUFF_SIZE]) > 0) {
for (NSUInteger i = 0; i < __count; i++) {
id obj = __objects[i];
[obj doSomething];
}
}
The problem is that, I found it wrong.
First of all, when you have Automatic Reference Counting (ARC) turned on, you got an error
Sending '__strong id *' to parameter of type '__unsafe_unretained_id*' changes retain/release properties of pointer
But even when I turn ARC off I found out that I __object array seems to behave strangely :
This is actual Code (I assumed MAX_STACKBUFF_SIZE to be 40):
#autoreleasepool {
NSArray *myArray = #[#"a", #"b", #"c", #"d", #"e", #"f", #"g"];
int MAX_STACKBUFF_SIZE = 40;
NSFastEnumerationState __enumState = {0};
id __objects[MAX_STACKBUFF_SIZE];
NSUInteger __count;
while ((__count = [myArray countByEnumeratingWithState:&__enumState objects:__objects count:MAX_STACKBUFF_SIZE]) > 0) {
for (NSUInteger i = 0; i < __count; i++) {
id obj = __objects[i];
__enumState.itemsPtr
NSLog(#" Object from __objects ! %#", obj); // on screenshot different message
}
}
}
return 0;
I got EXC_BAD_ACESS when I try to get the contents of the __object array.
I also found out that when you try to iterate through __enumState.itemsPtr it actually works.
Could you explain me what is going on here ? Why my __objects seems to be "shrunken down". And why it doesn't contains desired object? And why is that error when ARC is turned on.
Thank you very very much in advance for your time and effort! (I provided screenshot for better understanding what causes an error)
First of all, strong pointers cannot be used in C-structures, as explained in the "Transitioning to ARC Release Notes", therefore the objects array has be be declared
as
__unsafe_unretained id __objects[MAX_STACKBUFF_SIZE];
if you compile with ARC.
Now it is not obvious (to me) from the NSFastEnumeration documentation, but it is
explained in Cocoa With Love:Implementing countByEnumeratingWithState:objects:count:
that the implementation need not fill the supplied objects array, but can just set
__enumState.itemsPtr to an existing array (e.g. some internal storage). In that case, the contents of the
__objects array is undefined, which causes the crash.
Replacing
id obj = __objects[i];
by
id obj = __enumState.itemsPtr[i];
gives the expected result, which is what you observed.
Another reference can be found in the "FastEnumerationSample" sample code:
You have two choices when implementing this method:
1) Use the stack
based array provided by stackbuf. If you do this, then you must
respect the value of 'len'.
2) Return your own array of objects. If
you do this, return the full length of the array returned until you
run out of objects, then return 0. For example, a linked-array
implementation may return each array in order until you iterate
through all arrays.
In either case, state->itemsPtr MUST be a valid
array (non-nil). ...
I'm new to plists, and I really need to use one. What I have is a plist where different numbers are stored, under two dictionaries. I need to get that number which is stored, and make it an integer. This process will be run from a method called 'readPlist.
The plist is called 'properties.plist'. The first dictionary is called 'Enemies'. It contains various other dictionaries, which will have the name stored in the NSMutableString called 'SpriteType'. The name of the number will have the format 'L - %d', with the %d being an integer called 'LevelNumber'.
If possible, can someone give me the code on how to get that integer using the information, and the names of dictionaries above.
I have looked around at how to access plists, but the code that people have shown doesn't work.
Thanks in advance.
EDIT: Too make it more understandable, this is my plist. What i want in an integer, called 'SpriteNumber' to be equal to the value of 'L - %d'
If you read the contents of your plist into a dictionary (I won't tell you how to do it, but this is the tutorial I refer to often), then it's a matter of getting the string out of the key for the level with [[myDictionary objectForKey:#"key"]stringValue];. Then, using of NSString's extremely helpful -stringByReplacingOccurencesOfString:withString: to get rid of the "L -" part and only get a numerical value. Finally, get an integer from the string with [myString intValue].
well, the easiest way would be something like :
-(int) getMosquitoCountForLevel:(int) level {
int mosquitoCount=0;
NSString *gsFile = #"whateverFullyQualifiedFileNameYourPlistIs";
NSDictionary* definitions = [NSDictionary dictionaryWithContentsOfFile:gsFile];
NSDictionary* mosquitos = [definitions objectForKey:#"Mosquito"];
if(mosquitos) {
NSString *levelKey = [NSString stringWithFormat:#"L - %d",level];
NSNumber *mosquitoCountAsNumber = [mosquitos objectForKey:levelKey];
if(mosquitoCountAsNumber) {
mosquitoCount=[mosquitoCountAsNumber intValue];
} else {
CCLOGERROR(#"%# - Mosquito definitions in %# does not contain a en entry for level %#.",self.class,gsFile,levelKey);
}
} else {
CCLOGERROR(#"%# - file %# does not contain a Mosquito dictionary.",self.class,gsFile);
}
return mosquitoCount;
}
this compiles but not tested with actual data.
I need to scroll through several thousands of words to categorize them... to determine which words have the same pattern. (this part works)
For example, a four letter word that has two m's in 2nd & 4th position represent a pattern ("-m-m"). Once I have gone through all the words, I will know how many words there are for any given pattern. I am scrolling through now, but the problem I have is 'remembering' how many words I have in any given pattern.
I was thinking of using NSMutableDictionary and have the key be the pattern ('-m-m-') and the object represent the count of that pattern. This means every time I come across a pattern, I look up that pattern in the dictionary, get the key, increment the key, and put it back in the dictionary.
I need help with both the decision and syntax for performing this task.
Thank You
The answer to your question was this part of your (given) question "I will know how many words there are for any given pattern.". I would use an array of dictionary. You use the dictionary to store key value pair: a known pattern and the count. And you use the array to store those KVP records. So the next time you detect a pattern, search for the array for that record (dictionary), if found, increment the count. If not, create new record and set the count to 1.
Added sample code:
#define kPattern #"Pattern"
#define kPatternCount #"PatternCount"
-(NSMutableDictionary *)createANewDictionaryRecord:(NSString *) newPattern
{
int count = 1;
NSMutableDictionary *myDictionary = [NSMutableDictionary dictionaryWithObjectsAndKeys:
newPattern, kPattern,
[NSString stringWithFormat:#"%i",count], kPatternCount,
nil];
return myDictionary;
}
-(void)addANewPatternToArray:(NSMutableDictionary *)newDictionary
{
// NSMutableArray *myArrayOfDictionary = [[NSMutableArray alloc]init]; // you need to define it somewhere else and use property etc.
[self.myArrayOfDictionary addObject:newDictionary]; //or [self.myArrayOfDictionary addObject:newDictionary]; if you follow the recommendation above.
}
-(BOOL)existingPatternLookup:(NSString *)pattern
{
for (NSMutableDictionary *obj in self.myArrayOfDictionary)
{
if ([[obj objectForKey:kPattern] isEqual:pattern])
{
int count = [[obj objectForKey:kPatternCount] intValue] + 1;
[obj setValue:[NSString stringWithFormat:#"%i",count] forKey:kPatternCount];
return YES;
}
}
[self.myArrayOfDictionary addObject:[self createANewDictionaryRecord:pattern]];
return NO;
}
-(void)testData
{
NSMutableDictionary *newDict = [self createANewDictionaryRecord:#"mmm"];
[self addANewPatternToArray:newDict];
}
-(void) printArray
{
for (NSMutableDictionary * obj in self.myArrayOfDictionary)
{
NSLog(#"mydictionary: %#", obj);
}
}
- (IBAction)buttonPressed:(id)sender
{
if ([self existingPatternLookup:#"abc"])
{
[self printArray];
} else
{
[self printArray];
}
}
Not being an objective C expert but solving this problem in java before, I would say a dictionary(I used a map when doing it in java) is the best way. Check if the key(pattern) already exist if so increment that count else put a new one in the dictionary.
EDIT
If you want to not just get the count of a pattern, but in fact tell which words fall under that pattern, I would use a dictionary of strings to mutable arrays. In the arrays you store the words and the key to the array is the pattern(as a string), similar code as above but instead of just incrementing the count, you have to add the new word to the array.
The only difference in NSDictionary and NSMutableDictionary is that one can have objects added to it. I think your implementation is good, but English is a complex language. It would be more efficient to parse out the string with regex than to set a key for it.
Why don't you use NSCountedSet instead:
NSCountedSet Class Reference
..which is available in iOS 2.0 and later?
Each distinct object inserted into an NSCountedSet object has a counter associated with it. NSCountedSetkeeps track of the number of times objects are inserted [...] Thus, there is only one instance of an object in an NSSet object even if the object has been added to the set multiple times. The count method defined by the superclass NSSet has special significance; it returns the number of distinct objects, not the total number of times objects are represented in the set.
Then use:
- (NSUInteger)countForObject:(id)anObject
Use a dictionary of NSMutableArrays, and check for the existence of each search key as you recommended. If the key doesn't exist, add an NSMutableSet or NSMutableArray (depending on your needs) for the searched key type "-m-m" for example, and then add to the set or array for that key.