I have to assign countries, states & cities getting in response from JSON, in an NSMutableArray, Which is initialized in Modal Class.
I will have to remove all objects in order to set new states and cities, doing that crashes with error
incorrect checksum for freed object - object was probably modified
after being freed.
*** set a breakpoint in malloc_error_break to debug
then in answer https://stackoverflow.com/a/12050676/5568169 came to know that assigning nil to mutableArray will work, and it worked, But now User can again select another country, So now allocating memory [myMutableArray alloc] init]], gives me the same error i was getting in starting.
-(void)fetchStates:(NSString*)idString {
[registrationModalContactVC.allStateArray removeAllObjects];
registrationModalContactVC.allStateArray = nil;
[registrationModalContactVC.allStateDict removeAllObjects];
registrationModalContactVC.allStateDict = nil;
registrationModalContactVC.allStateArray = [NSMutableArray new];
registrationModalContactVC.allStateDict = [NSMutableDictionary new];
}
Kindly help
You should not be dong this :
[myMutableArray alloc] init]
What you mean to do is :
myMutableArray = [[NSMutableArray alloc] init];
i think your mutablearray is a datasource of a pickview , when you remove all objects, how is your pickview's status.
Removing below code is working, but it may give the same error again
registrationModalContactVC.allStateArray = nil;
registrationModalContactVC.allStateDict = nil;
registrationModalContactVC.allStateArray = [NSMutableArray new];
registrationModalContactVC.allStateDict = [NSMutableDictionary new];
Related
I have a very strange behaviour with NSArray.
Firstly, i parsed an XML file and return a valid NSArray with NSDictionary inside:
NSArray *arrayOfDict = [parser parseWithXMLFile:filename];
In debugger it's fully valid. Then, i want to proccess all dictionaries in this array:
NSMutableArray* arrayOfProducts = [[NSMutableArray alloc] init];
for (NSDictionary* dict in arrayOfDict) {
Product* product = [[Product alloc] initWithName:dict[#"name"]
type:dict[#"type"]
imageName:dict[#"image"]
description:dict[#"description"]];
[arrayOfProducts addObject:product];
[product release];
}
And in this loop is a problem: a dict variable has value nil. And i don't know what to do with this. In debugger i evaluate value of arrayOfDict[someIndex] and get a right value, but in the programm itself it doesn't work.
May be it's the problem with MRR, i don't feel myself confidenly while using MRR and there is a mistake of using it.
P.S. I know that using MRR is stupid today, but in this project i must use it.
I am using textfield for the user to enter his username and password to signup and then store it in an array. But when i log my array it shows null. This is my code
User = self.Username.text;
UserPassword = self.UserPass.text;
LoginPageViewController *loginPage;
[loginPage.registeredUsernames addObject:User];
[loginPage.registeredPassword addObject:UserPassword];
NSLog(#"%#", loginPage.registeredUsernames);
NSLog(#"%#", loginPage.registeredPassword);
Please help
loginPage is a variable only declared, but is not instanciated any object. This means that is nil, we you send the message loginPage.registeredUsernames nothing happens because no object exist to handle that message.
Have you initialise your mutable array? If not try initialise the array and save the direct values in array like,
[loginPage.registeredUsernames addObject:self.Username.text];
[loginPage.registeredPassword addObject:self.UserPass.text];
I take it that your LoginPageViewController object's properties registeredUsernames and registeredPassword are NSMutableArrays.
If that is indeed the case, given you code, you will need to instantiate the LoginPageViewController *loginPage and make sure that in the init method for this object you are properly instantiating the registeredUsernames and registeredPassword properties. Something to the effect of:
...
_registeredUsernames = [NSMutableArray new];
_registeredPassword = [NSMutableArray new];
...
Note that the code you posted is not initializing the loginPage object, perhaps that is a typo in the post, otherwise you will need to initialize the object before using it.
Hope this helps.
You have not instantiated your object. Try this code :
User = self.Username.text;
UserPassword = self.UserPass.text;
NSMutableArray *arrayUsernames = [[NSMutableArray alloc] init];
NSMutableArray *arrayPasswords = [[NSMutableArray alloc] init];
LoginPageViewController *loginPage = [[LoginPageViewController alloc] initWithNibName:#"LoginPageViewController" bundle:nil];
[arrayUsernames addObject:User];
[arrayPasswords addObject:UserPassword];
loginPage.registeredUsernames = arrayUsernames;
loginPage.registeredPassword = arrayPasswords;
First initiate LoginPageViewControllers object and registeredUsernames,registeredPassword array then directly pass your textfield value to array. Try this code
LoginPageViewController*loginPage = [[LoginPageViewController alloc] initWithNibName:#"LoginPageViewController" bundle:nil];
loginPage.registeredUsernames=[[NSMutableArray alloc]init];
loginPage.registeredPassword=[[NSMutableArray alloc]init];
[loginPage.registeredUsernames addObject:self.Username.text];
[loginPage.registeredPassword addObject:self.UserPass.text];
NSLog(#"%#", loginPage.registeredUsernames);
NSLog(#"%#", loginPage.registeredPassword);
i am constructing All data to look like a response data dictionary from a server.
Now, newsFeedsDict1 which should Dictionary for both Bolly and Global is not only showing all data inside Global dictionary only. While my for loop is running its showing correct data for Bolly. but for 2nd time its showing Bolly's data also in Global dictionary.
if(internetStatus == NotReachable)
{
NSMutableArray *titleArr = [[NSMutableArray alloc] init];
NSMutableArray *wholeFeeds = [[[NSMutableArray alloc] init] autorelease];
[titleArr addObject:#"Bolly"];
[titleArr addObject:#"Global"];
for (NSString *title in titleArr) {
//titleArr = [[NSUserDefaults standardUserDefaults] objectForKey:#"TitleArray"];
NSLog(#"TITle arr %#",titleArr);
NSLog(#"No internet");
OrderedDictionary *newsFeedsDict1 = [[[OrderedDictionary alloc] init] autorelease];
NSMutableDictionary *newsFeedsDict = [[[NSMutableDictionary alloc] init] autorelease];
NSMutableArray *myLocalArray= [[[NSMutableArray alloc] init] autorelease];
myLocalArray = [[Database sharedDatabase] getArticleData:title];
NSMutableDictionary *articleDict = [[[NSMutableDictionary alloc] init] autorelease];
[articleDict setObject:myLocalArray forKey:#"article"];
[newsFeedsDict setObject:articleDict forKey:#"Articles"];
[newsFeedsDict setObject:title forKey:#"#name"];
[newsFeedsDict1 setObject:newsFeedsDict forKey:title];
[wholeFeeds addObject:newsFeedsDict1];
NSLog(#"news feed dict %#",newsFeedsDict1);
NSMutableDictionary *temparticleDictionary = [[NSMutableDictionary alloc] init];
self.articleDictionary = temparticleDictionary;
self.categoriesDictionary = [[NSMutableDictionary alloc] init];
self.categoriesDictionary =newsFeedsDict1;
[self createArticleDictionaryForCategory:newsFeedsDict];
}
}
It's difficult to tell what your code is supposed to do, and how you can tell that one dictionary has the same content as another. A couple problems:
NSMutableArray *myLocalArray= [[[NSMutableArray alloc] init] autorelease];
myLocalArray = [[Database sharedDatabase] getArticleData:title];
The first line is entirely unnecessary. You're creating a new array, assigning it to myLocalArray, and then assigning something else to myLocalArray. You do the same later with self.categoriesDictionary. This leads me to believe that you have some misunderstanding with respect to object pointers.
So, the array that you get from your shared database ends up at myLocalArray, and you then add that array to the dictionary at articleDict, and then add articleDict to newsFeedDict and in turn add that to newsFeedDict1. And then you log newsFeedDict1. You do exactly the same for both your titles, #"Bolly" and #"Global", so it's not at all surprising that you see the same output in both cases.
I'm having a hard time seeing why you expect the output to be different, and I have to guess that again it's due to a misunderstanding of what happens when you assign one object pointer to another. Or, perhaps you're expecting the array that you get from [[Database sharedDatabase] getArticleData:title]; to be different because you're passing in different titles. Maybe you really should be getting different arrays there; it would be a good idea to look at what happens in that -getArticleData: method and whether it really is giving you the right results for each title.
If that doesn't help, take some time to clean up your code so that it's easier for us, and more importantly, for you to really see what's going on. Also, please edit your question to give a better description of what you're seeing and how that's different from what you expect to see.
Can you write the snippet for *getArticleData()* method
I am pretty new to objective c and iOS programming, and I have this pretty strange error. The app in question initializes a NSMutableArray with a preset set of values of a custom type I made using NSObject. Which is manipulated by the app. If new values are added during app run time, they are saved using NSUserDefaults, and are brought up from NSUserDefaults along with the default values on next app open.
This is the error I get:
Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<__NSCFConstantString 0xb404> valueForUndefinedKey:]: this class is not key value coding-compliant for the key score.'
*** First throw call stack:
(0x1c9b012 0x10d8e7e 0x1d23fb1 0xb84d1d 0xaf100b 0xaf0fbd 0xb0f247 0xb3023c 0xb30056 0x3e40 0x3c5f 0x11f5ad 0x10ec705 0x202c0 0x20258 0x242ff4 0x10ec705 0x202c0 0x20258 0xe1021 0xe157f 0xe1056 0x246af9 0x10ec705 0x202c0 0x20258 0xe1021 0xe157f 0xe06e8 0x4fcef 0x4ff02 0x2dd4a 0x1f698 0x1bf6df9 0x1bf6ad0 0x1c10bf5 0x1c10962 0x1c41bb6 0x1c40f44 0x1c40e1b 0x1bf57e3 0x1bf5668 0x1cffc 0x290d 0x2835)
libc++abi.dylib: terminate called throwing an exception
I am not quite sure what the error is or how to go about debugging it.
Previously this code worked flawlessly, all I did was remove one or two elements from the preset default list of elements, and in the simulator, simulated deleting the app, and recompiled the code. Ever since my program crashes, with the above message, and I can't figure out how to fix it.
So if someone can give me some help on how to go about debugging this, that would be wonderful. I can attach code as needed, i'm not sure what code would be relevant to be shown, and it may be too much to post all the code involved in the project.
Code to encode and decode the properties of my custom Name NSObject class called name.h:
-(void)encodeWithCoder:(NSCoder *)encoder
{
[encoder encodeObject:self.name forKey:#"name"];
[encoder encodeInteger:self.score forKey:#"score"];
}
-(id)initWithCoder:(NSCoder *)decoder
{
if((self = [super init]))
{
self.name = [decoder decodeObjectForKey:#"name"];
self.score = [decoder decodeIntegerForKey:#"score"];
}
return self;
}
Retrieving Data from class, incase this matters, this code occurs in appdelegate.m:
NSData *data = [[NSUserDefaults standardUserDefaults] objectForKey:#"dataArray"];
NSInteger score = 0;
NSMutableArray *temp = [[NSMutableArray alloc] initWithObjects:#"name", nil];
NSMutableArray *tempList = [[NSMutableArray alloc] init];
for(NSString *y in temp)
{
Name *name = [[Name alloc] init];
name.name = y;
name.score = score;
[tempList addObject:name];
}
if (data)
{
NSArray *list = [NSKeyedUnarchiver unarchiveObjectWithData:data];
NSMutableArray *names = [[NSMutableArray alloc]initWithArray:list];
// [_nameList addObjectsFromArray:temp];
NSMutableArray *t = [[names arrayByAddingObjectsFromArray:tempList ] mutableCopy];
_nameList = [[NSMutableArray alloc]init];
[_nameList addObjectsFromArray:t];
}
else
{
//First time load or data is not saved yet
_nameList = [[NSMutableArray alloc] initWithObjects:#"name", nil];
}
saving the array at close time:
- (void)applicationWillTerminate:(UIApplication *)application
{
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
NSData *data =[NSKeyedArchiver archivedDataWithRootObject:_nameList];
[[NSUserDefaults standardUserDefaults] setObject:data forKey:#"dataArray"];
}
same code is in applicationDidEnterBackground.
code to sort by 'score'
- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController: (UIViewController *)viewController
{
if(viewController == _viewController3)
{
[self sortNames:_nameList];
[[(ThirdViewController*)_viewController3 topList] reloadData];
}
}
-(void)sortNames:(NSMutableArray*)test
{
NSArray* temp = [[NSArray alloc] initWithArray:test];
NSSortDescriptor *sortDescriptor = [NSSortDescriptor sortDescriptorWithKey:#"score" ascending:NO];
NSArray *sortedLinks = [[temp sortedArrayUsingDescriptors:[NSArray arrayWithObject:sortDescriptor]] mutableCopy];
_nameList = (NSMutableArray*) sortedLinks;
}
Here's my two cents. You have this line:
[encoder encodeObject:self.name forKey:#"name"];
And then this line:
Name *name = [[Name alloc] init];
This makes me think that the "self.name" property is one of these "Name" custom subclasses.
I believe that if you make a custom subclass and you want it to encodewithcoder, you have to add the encodewithcoder method to your custom subclass and have it encodewithcoder all of its properties and instance variables as primitively as you can.
Meaning, your Name class needs to have its own encodewithcoder method that encodes all of its properties and instance variables that have been stored as factory objects or c primitives.
Edit: I'm still pretty new and value my rep. If I'm wrong, please comment and I'll delete but please don't downvote me to oblivion
Here:
_nameList = [[NSMutableArray alloc] initWithObjects:#"name", nil];
you are adding an NSString to the _nameList array. Later you save that array.
The next time you load that array, you have the NSString #"name" in it. I guess at some point you iterate through the items in _nameList and try to get or set the score, since you are calling this on a subclass of NSString you get the NSUnknownKeyException.
I think what you want to is to replace the line above with something like this: (assuming the class in your name.h file you mentioned above is called Name)
Name *newName = [[Name alloc] init]; //or initialize the way you need to
_nameList = [[NSMutableArray alloc] initWithObjects:newName, nil];
arrayOfElements = [NSMutableArray arrayWithArray:[someObj getArray]];
and
arrayOfElements = [[NSMutableArray alloc] init];
arrayOfElements = [someObj getArray];
What's the difference?
The first arrayOfElements does not seem to lose its objects when it returns count in numberOfRowsInSection:(NSInteger)section, but the second one does. I get EXC_BAD_ACCESS when I do it the second way.
EDIT:
Can I suppose now that this is the best way,
arrayOfElements = [[NSMutableArray alloc] initWithArray:[someObj getArray]];
because I am initializing an array with the contents of whatever will be autorelease'd, and I now have a fully independent array in the current class, that is viewDidLoad, oops sorry, ViewController.
This line creates an NSMutableArray from an existing array
arrayOfElements = [NSMutableArray arrayWithArray:[someObj getArray]];
This combination first creates an NSMutableArray and then instantly discards it replacing it with what is returned by [someObj getArray]
arrayOfElements = [[NSMutableArray alloc] init]; // Create new NSMutableArray
arrayOfElements = [someObj getArray]; // Throw away the newly created array and replace with the result of [someObj getArray]
If you are not using ARC then it is purely by luck that either would work.
In both cases arrayOfElements is being assigned an autorelease'd object - which will be cleared soon (most likely the next runloop). It is only by chance that nothing else has been written over this point of memory which allows one of your implementations to still work.
If you are not using ARC then really you should update your project to be using it will handle a lot of cases like this for you.
You should definitely be using properties (not bare ivars) as this will help reduce memory issues (for non-ARC) and give a more consistent interface to your code.
In your header (or class extension) declare the property like this
#property (nonatomic, strong) NSMutableArray *arrayOfElements;
Now for ARC you can simple do
[self setArrayOfElements:[[someObj getArray] mutableCopy];
for non-ARC you can do
NSMutableArray *array = [[someObj getArray] mutableCopy];
[self setArrayOfElements:array];
[array release]; array = nil;
Also note that getArray is a bad method name.
The use of “get” is unnecessary, unless one or more values are returned indirectly.
Coding Guidelines
When you are adding objects to mutable array from another array, try this:
[arrayOfElements addObjectsFromArray: [someObj getArray]];
If you're not using ARC, you need to make sure its retained.
if (arrayOfElements) {
[arrayOfElements release];
}
arrayOfElements = [[NSMutableArray alloc] initWithArray:[someObj getArray]];