I have this curious thinf happening here where tempArray is supposed to be added to the masterArray each time the if statement occurs. (The if statement works perfectly and gets triggered when it should.)
I also need to clear the temp array each time it does.
My final result should then be a masterarray which contains each array it has added.(meaning all the temp arrays that I have added throughout the for loop)
Instead, it only keeps adding the tempArray to the MasterArray at index 0 every single time.
Code:
- (void)alpabetize:(NSArray *)arr {
self.tempArray = [[NSMutableArray alloc] init];
self.masterArray = [[NSMutableArray alloc] init];
for (int i = 0; i<[arr count]; i++) {
NSString *currentString = [NSString stringWithFormat:#"%#", [[[arr objectAtIndex:i] valueForKey:#"first_name"] substringToIndex:1]];
NSString *nextString = [NSString stringWithFormat:#"%#", [[[arr objectAtIndex:(i+1)] valueForKey:#"first_name"] substringToIndex:1]];
[self.tempArray addObject:[arr objectAtIndex:i]];
if (![currentString isEqualToString:nextString]) {
[self.masterArray addObject:tempArray];
[self.tempArray removeAllObjects];
}
}
}
If you remove all objects from the original array previously added to some other array. Does this also clear the other array? This makes no sense to me. There must be something wrong in my code. Can somebody help me spot my error?
Thank you for your time!
Use
[self.masterArray addObject:[tempArray copy]]; // retained copy of array
or
[self.masterArray addObject:[NSArray arrayWithArray:tempArray]]; // auto released copy of array
instead of
[self.masterArray addObject:tempArray];
In your code you are adding the reference of the same array which you are clearing in next statement.
[self.masterArray addObjectsFromArray:tempArray];
[tempArray removeAllObjects];
Are you sure you want to release the self.tempArray inside the loop? Once it enters your IF-condition the the array will be nil and you'll have no use of it unless you call the this method again. Try releasing the self.tempArray after the for loop.
Related
sorry if the title is worded oddly, not really sure how to say it. I am adding contents of an array of object's from a JSON into another array, so I can do use a sectioned UITableView. However, when I do the removeAllObjects function call when I've filled enough for the first section, add them to my array, and start to load up the second, it results in the entire first section being replaces by the second section. Is NSMutableArray at fault, or is it something I am not thinking of?
weekScheduleArray = [[NSMutableArray alloc] initWithCapacity:2];
NSMutableArray *temp = [[NSMutableArray alloc] init];
for (int count = 0; count < [jsonObject count]; count++) {
if (count < 7) {
[temp addObject:[jsonObject objectAtIndex:count]];
} else if (count == 7) {
[weekScheduleArray addObject:temp];
[temp removeAllObjects];
[temp addObject:[jsonObject objectAtIndex:count]];
} else {
[temp addObject:[jsonObject objectAtIndex:count]];
}
}
[weekScheduleArray addObject:temp];
Calling [weekScheduleArray addObject: temp] does not add a copy of temp to weekScheduleArray; it adds the array itself. Therefore when you subsequently removeAllObjects from temp then the array in weekScheduleArray is also empty. You can avoid the issue with:
[weekScheduleArray addObject: [temp copy]];
The problem is you are continuing to manipulate the exact same mutable array that you just added to the weekScheduleArray. There's a bunch of ways to solve this. You could create a copy when you add it to weekScheduleArray:
[weekScheduleArray addObject:[temp copy]];
Or you could do this:
[weekScheduleArray addObject:temp];
[temp release];
temp = [[NSMutableArray alloc] init];
[temp addObject:[jsonObject objectAtIndex:count]];
And then when you are done your for loop, remember to release temp.
I had stored custom objects data in Array. I am fetching data from Array of custom objects in a function. when I am calling function for first time it is working good but When I am calling it again and again I am getting EXC_BAD_ACCESS.
Here is function details.
-(void) facebookDisplayFunction:(int)atIndex {
FacebookWallData *wall = (FacebookWallData *)[facebook_wallDataArray objectAtIndex:atIndex];
NSString *friendID= wall.actor_id;
NSString *linkFetch= wall.permalink;
NSString* postID=wall.postId;
NSNumber *countNumber;
NSString *friendName=#"";
NSString* profileThumImage=#"";
for(int i=0; i< [facebook_LikesArray count];i++) {
FacebookLikes* countValues=[[FacebookLikes alloc]init];
countValues=[facebook_LikesArray objectAtIndex:i];
// NSLog(#" postId_wall %# LikePostId = %#",postID,countValues.PostID);
if([postID isEqualToString:countValues.PostID]) {
countNumber=countValues.Count;
if(countNumber>0)
friendID=countValues.Friends;
[countValues release];
break;
}
[countValues release];
}
for(int i=0;i< [facebook_FreindsArray count];i++) {
FacebookFreinds* friendsRecord=[[FacebookFreinds alloc]init];
friendsRecord=[facebook_FreindsArray objectAtIndex:i];
if([friendID isEqualToString:friendsRecord.UID]) {
friendName=friendsRecord.name;
profileThumImage=friendsRecord.pic_smal;
[friendsRecord release];
break;
}
[friendsRecord release];
}
// Adding values in table //
[imageData addObject:#"facebook.png"];
[tableList addObject:wall.messages];
[profileUserName addObject:friendName];
[linksOfFacebookData addObject:linkFetch];
[RetweetAndLikeData addObject:#"5"];
[favedProfileThumb addObject:profileThumImage];
[twitterPostID addObject:#""];
[eachPostUID addObject:friendID];
[wall release];
}
And here I am calling function.
[self facebookDisplayFunction:0];
[self facebookDisplayFunction:0]; // EXC_BAD_ACCESS error here.
Why are you allocating an object like this FacebookLikes* countValues=[[FacebookLikes alloc]init] and then assigning to this same variable the instance inside the array with this code countValues=[facebook_LikesArray objectAtIndex:i] and later on you release it with this [countValues release]? You don't know what you are doing.
Try changing this:
FacebookLikes* countValues=[[FacebookLikes alloc]init];
countValues=[facebook_LikesArray objectAtIndex:i];
to this
FacebookLikes* countValues = [facebook_LikesArray objectAtIndex:i];
and remove all occurrences of [countValues release]. Do the same for the friendsRecord in the second for-loop. Also, what is the [wall release]? Remove it!
You should not allocate any of these objects because you are actually obtaining them from that array, and not creating a new instance. That just creates a leak in your code. You should not release any of these objects because they are retained by the array, and it is responsible for releasing them whenever they are removed from the array or after the array is destroyed/deallocated. Please, rtfm
If you get the error on the line:
[self facebookDisplayFunction:0];
it seems to me that most likely the object pointed by self has been deallocated. So, the problem would not be in facebookDisplayFunction...
Could you review how you create the object pointed by self, or post the code if you need more help?
I've got a problem. I'm trying to sort the items from 1 array (name: mps) into an other array (name: totalArray), but every item should be in a new array. In short: the items in mps should move into a new array, but every item should be in a new array, so the totalArray is an array of arrays. After that, totalArray should be copied back into mps.
To clarify, here is the code:
NSMutableString *oud = [[NSMutableString alloc] init];
NSMutableString *nieuw = [[NSMutableString alloc] init];
NSMutableArray *tempArray = [[NSMutableArray alloc] init];
[tempArray removeAllObjects];
NSMutableArray *totalArray = [[NSMutableArray alloc] init];
[totalArray removeAllObjects];
tempArray = [[NSMutableArray alloc] init];
[tempArray removeAllObjects];
for (int j = 0; j < [mps count]; j++)
{
nieuw = [[mps objectAtIndex:j] valueForKey:#"ConfigurationAlias"];
if (j != 0)
{
if ([oud rangeOfString:nieuw].location == NSNotFound)
{
NSLog(#"ADDED!");
[totalArray addObjectsFromArray:tempArray];
[oud setString:nieuw];
[tempArray removeAllObjects];
[tempArray addObject:[mps objectAtIndex:j]];
}
else
{
[tempArray addObject:[mps objectAtIndex:j]];
}
}
else {
[oud setString:nieuw];
[tempArray addObject:[mps objectAtIndex:j]];
}
}
//En de array weer laden in de tabel
//NSLog(#"%#", totalArray);
NSLog(#"%i", [mps count]);
[mps removeAllObjects];
NSLog(#"REMOVED!!!");
NSLog(#"%i", [mps count]);
[mps addObjectsFromArray:totalArray];
NSLog(#"Added totalArray: %i", [totalArray count]);
NSLog(#"%i", [mps count]);
[tempArray release];
[totalArray release];
[tabelView reloadData];
}
Now, here comes my problem:
The log gives the line 2011-04-07 10:02:46.368 Fleet Manager[901:40b] ADDED! 11 times, then it posts 16 (mps count, this is correct), then the line REMOVED!, then 0 (mps count, also correct), but then the line: Added totalArray: 15. This can't be correct, it added 11 times but it counts 15?
This a problem for me, in the first place because it's plain incorrect, but the tableview gets screwed up as well because of the section-amount not being correct either (15 sections). Anybody has any idea what's going on?
EDIT: all the objects in mps are dictionaries, and all of them have a value for the key "ConfigurationAlias".
First, I would like to suggest using debugging mode instead of bunch of NSLog functions to track down what's actually happening inside your objects and variables. Try using breakpoints. Set one for [totalArray addObjectsFromArray:tempArray]; line so every time this line of code is reached the execution would stop and let you look around, check different fields' states inside totalArray and tempArray objects.
Concerning your problem... Since you are using addObjectsFromArray: that means that passed array may pass not one but several objects (thus the plural in method name). I guess one of those "11 times" added more than one element - that should explain the actual count being more than the times you've called this method. Again, please check tempArray contents.
Good luck!
If you want to end up with an array of arrays, you need to be allocating temp arrays inside the loop. It also seems like you are overdoing it with clearing out the arrays.
It appears you are trying to add the value from mps to totalArray regardless of the conditions, so it would make sense to only do that in one place (outside of the conditions).
Also, if you are not mutating the arrays (such as tempArray), you can use NSArray instead, which should be smaller and faster.
Finally, you should be able to assign the new array to mps instead of doing the expensive array copying. Not sure if that is somehow referenced as the table delegate, though.
I would try something like:
NSMutableString *oud = [[NSMutableString alloc] init];
NSMutableString *nieuw = [[NSMutableString alloc] init];
NSMutableArray *tempArray;
NSMutableArray *totalArray = [[NSMutableArray alloc] init];
for (int j = 0; j < [mps count]; j++)
{
tempArray = [[NSMutableArray alloc] init];
[totalArray addObject:tempArray];
[tempArray release];
nieuw = [[mps objectAtIndex:j] valueForKey:#"ConfigurationAlias"];
if (j != 0)
{
if ([oud rangeOfString:nieuw].location == NSNotFound)
{
NSLog(#"ADDED!");
[oud setString:nieuw];
}
}
else {
[oud setString:nieuw];
}
}
NSLog(#"%i", [mps count]);
[mps removeAllObjects];
NSLog(#"REMOVED!!!");
NSLog(#"%i", [mps count]);
[mps addObjectsFromArray:totalArray];
NSLog(#"Added totalArray: %i", [totalArray count]);
NSLog(#"%i", [mps count]);
[totalArray release];
[tabelView reloadData];
}
You should
sort the base array in a tempArray
create an empty resultArray
iterate through tempArray and for each item create an itemArray containing the item on the first position and add this array to resutArray
don't forget to release all alloc-ed temporary data
Check this out for sorting easily: Sorting arrays via Apple
I have an NSMutableArray which only lasts during the session.
Currently I create it like this
NSMutableArray *temp = [[NSMutableArray alloc] initWithCapacity:10];
[self setScoreArray:temp];
[temp release];
Problem is when I go to check each index I'm getting an array outofbounds error
NSNumber *previousScore = [[self scoreArray] objectAtIndex:[self quizNum]];
if ( previousScore != nil )
{
[self clearQuizBtns];
NSInteger previousScoreValue = [previousScore integerValue];
[self selectButtonAtTag:previousScoreValue];
}else {
[self clearQuizBtns];
}
I've read in other posts that initWithCapacity doesn't actually create the array. So what can I populate the array with initially?
Thanks in advance.
Two ways:
first: to initiate array with default values of NSNull class
NSMutableArray *temp = [[NSMutableArray alloc] initWithCapacity:10];
for (int i = 0 ; i < 10 ; i++)
{
[temp insertObject:[NSNull null] atIndex:i];
}
[self setScoreArray:temp];
[temp release];
and then to check: if object is kind of NSNull class means it was a never set before
id previousScore = [[self scoreArray] objectAtIndex:[self quizNum]];
if (![previousScore isKindOfClass:[NSNull class]])
{
[self clearQuizBtns];
NSInteger previousScoreValue = [(NSNumber *)previousScore integerValue];
[self selectButtonAtTag:previousScoreValue];
}else {
[self clearQuizBtns];
}
second: store scores in NSMutableDictionary and use NSNumber's as keys
// scoreDictionary property of NSMutableDictionary class must be declared in self
NSNumber *previousScore = [self.scoreDictionary objectForKey:[NSNumber numberWithInt:[self quizNum]]];
if (previousScore != nil)
{
[self clearQuizBtns];
NSInteger previousScoreValue = [previousScore integerValue];
[self selectButtonAtTag:previousScoreValue];
}else {
[self clearQuizBtns];
}
NSArray does not support "holes". The capacity is just a hint to the initializer.
You could either fill the array with placeholder objects or, more typically, change your algorithm to either fully prepopulate the array or to lazy load it linearly.
Your problem seems to be that you're never actually setting any score in the score array.. are you? NSArrays have an actual count of items in them, and accessing an index beyond that count will blow up, as you've seen. If there will only ever be a fixed (small) number of scores, like 10, then you could set them all initially to something default like:
for (int i = 0; i < 10; i++) {
[temp addObject:[NSNumber numberWithInt:0]];
}
P.S. -initWithCapacity does "create the array", it just doesn't create any objects in the array. The capacity is a hint only.
Using the arrayWithObject: or arrayWithObjects: methods can provide an array with pre-populated values.
One cool thing about NSMutableArrays is that you can just do an "init" and the array will handle adding and removing objects on the fly. Remember that you generally addObject: or removeObjectAtIndex: when dealing with mutable arrays.
Just a conceptual description first:
I am reading input from a text file (a list of words) and putting these words into an NSArray using componentsSeparatedByString method. This works.
But I wanted to select the words randomly and then delete them from the array so as to ensure a different word each time. Of course, you cannot change the NSArray contents. So...
I copied the contents of the NSArray into an NSMutableArray and use IT for the selection source. This also works - 269 objects in each array.
To return a word from the NSMutableArray I use the following code:
note- the arrays are declared globally
as
arrMutTextWords = [[NSMutableArray alloc] init]; //stack for words
arrTextWords = [[NSArray alloc] init]; //permanent store for words
-(NSString*) getaTextWord
{
// if the mutable text word array is empty refill
if ([arrMutTextWords count] == 0){
for (int i = 0 ; i < [arrTextWords count]; i++)
[arrMutTextWords addObject:[arrTextWords objectAtIndex:i]];
}
int i = random() % [arrMutTextWords count];
NSString* ptrWord = [arrMutTextWords objectAtIndex:i];
[arrMutTextWords removeObjectAtIndex:i];
return ptrWord;
}
The program crashes during a call to the method above - here is the calling code:
arrTmp is declared globally arrTmp = [[NSArray alloc] init]; //tmp store for words
for (int i = 0 ; i < 4; i++) {
tmpWord = [self getaTextWord];
[arrTmp addObject:tmpWord];
[arrTmp addObject:tmpWord];
}
I'm thinking that somehow deleting strings from arrMutTextWords is invalidating the NSArray - but I can't think how this would occur.
One possible source for problems is your fetching AND removing the NSString object from your list. Removing it releases that NSString instance therefore devalidating your reference.
To be shure to retain a reference you should use this code sequence instead:
NSString * ptrWord = [[[arrMutTextWords objectAtIndex:i] retain] autorelease];
[arrMutTextWords removeObjectAtIndex:i];
return ptrWord;
By the way: You should use
NSMutableArray *mutableArray = [NSMutableArray arrayWithArray: array];
instead of copying all values by hand. While i do not know the implementation of NSMutableArray, i know from times long ago (NeXTstep), that there are several possible optimizations that may speed up basic NSArray operations.
And finally copying this way is much more concise.
Just ran this through XCode and got random words returned, however I skipped the whole for loop and used addObjectsFromArrayfrom NSMutableArray.
NSArray *randomArray = [[NSArray alloc] initWithObjects:#"Paul", #"George", #"John", nil];
NSMutableArray *muteArray = [[NSMutableArray alloc] init];
[muteArray addObjectsFromArray:randomArray];
int i = random() % [muteArray count];
NSString* ptrWord = [muteArray objectAtIndex:i];
[muteArray removeObjectAtIndex:i];
NSLog(#"ptrWord %#", ptrWord); //gave me a different name each time I ran the function.
Hope this clears some things up.