I feel like I have read many (simple) examples that do exactly what I am trying to do. I just cannot seem to get this to work. I need a second eye on my code, and I don't have anyone around, so pardon me if this seems very simple... The code compiles without a problem. Thank you!
#implementation Engine
- (id) initWithInventory: (NSString *) path {
if (self = [super init]) {
NSString *contents = [NSString stringWithContentsOfFile:#"ingredientList.csv" encoding:NSASCIIStringEncoding error:nil];
NSLog(#"%#",contents); // This yields the contents of the file appropriately
NSArray *lines = [contents componentsSeparatedByCharactersInSet:[NSCharacterSet newlineCharacterSet]];
NSRange ingredientRange = {0,96}; // This is done because I want to omit the last element of the array... the 97th is an empty string caused by the end of file newline character. I know it's bad coding...
NSEnumerator *enumerator = [[lines subarrayWithRange:ingredientRange] objectEnumerator];
NSString *curString;
NSArray *ingredientElements;
NSRange activeEffectRange = {1,4}; // Element 0 will be the key, elements 1-4 are the array to be stored.
while (curString = [enumerator nextObject]) {
ingredientElements = [curString componentsSeparatedByString:#","];
Ingredient *theIngredient = [[Ingredient alloc] initWithName:[ingredientElements objectAtIndex:0] andActiveEffects:[ingredientElements subarrayWithRange:activeEffectRange]];
NSLog(#"%#",[theIngredient ingredientName]);
NSLog(#"%#",[theIngredient activeEffects]); //These both print out correctly.
NSString *theName = [theIngredient ingredientName];
[allIngredients setObject:theIngredient forKey:theName];
NSLog(#"%#",[allIngredients objectForKey:[theIngredient ingredientName]]); // ***This yields (null)***
}
}
return self;
}
EDIT: I should add, that allIngredients is an instance variable of the class being initiated, so it is defined properly as an NSMutableDictionary:
#interface Engine : NSObject {
NSMutableDictionary *allIngredients;
}
- (id) initWithInventory: (NSString *) path;
#end
Where are you creating allIngredients? You've declared it, but you haven't allocated it before you use it.
allIngredients = [[NSMutableDictionary alloc] init]
Related
Now I have a textview ,and I receive content message , I will do
NSString *speakText=[[NSString alloc]initWithFormat:#"%#\n%#\n%#",fromWho,content,_cheatView.text];
to show it .
But now I want to create a array to save all message ,
In a array like sample
> [0] (first message 3pair key/value)
>[0]
>[1]
>[2]
>[1] (second message 3pair key/value)
>[2]
>[x]
>[y]
I tried use
- (void)webSocket:(SRWebSocket *)webSocket didReceiveMessage: (id)message;
{
NSString *toMessageJson = [[NSString alloc]initWithString:message];
[toMessageJson dataUsingEncoding:NSUTF8StringEncoding];
NSData *toMessageData =[toMessageJson dataUsingEncoding:NSUTF8StringEncoding];
NSError *error = nil;
NSDictionary *messageDic = [NSJSONSerialization JSONObjectWithData:toMessageData options:NSJSONReadingAllowFragments error:&error];
NSMutableArray *logDic =[NSMutableArray alloc];
[messageDic enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL * stop) {
if ([key isEqualToString:#"content"]) {
[logDic addObject:messageDic];
}
}];
But the logArray always only have 1 Object .
I think that logDic is confusing. At first I thought logDic is a dictionary, proper naming should also take place.
Main issue I can see is that you are always creating logDic every time you receive a message.
So if you make logDic as a property or an iVar.
example:
//WhatEverClassname
#interface WhatEverClassname(){
NSMutableArray *logDic;
}
#end
#implementation WhatEverClassname
-(id)init{
if(!(self = [super init])){
return nil;
}
logDic = [NSMutableArray new];
return self;
}
#end
then in your didReceived method you don't need to initialise it anymore.
This enumeration isn't actually needed.
[message enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL * stop) ]
it should be like:
if(message[#"content"] != nil)
[logDic addObject:message[#"content"]]; // no point in looping if you are only expecting a specific key.
I'm trying to make an app with Objective C.
I'm trying to serialise an array existing out of objects and after wards deserialise it. Inside the object there are the methods
(id)initWithCoder:(NSCoder *)coder` and `encodeWithCoder:(NSCoder *)coder
But it seems the "rootObject" stays "nil" in the "loadDataFromDisk" -method
Here is my code :
#import "Alarm.h"
#implementation Alarm
#synthesize array = _array;
#synthesize time = _time;
#synthesize coder = _coder;
-(id)initWithCoder:(NSCoder *)coder
{
self = [super init];
if(self)
{
_array = [coder decodeObjectForKey:#"array"];
_time = [coder decodeObjectForKey:#"time"];
}
return self;
}
-(void)encodeWithCoder:(NSCoder *)coder
{
[coder encodeObject:self.array forKey:#"array"];
[coder encodeObject:self.time forKey:#"time"];
}
#end
My save and load methods :
-(void)saveDataToDisk
{
NSString * path = [self pathForDataFile];
NSLog(#"Writing alarms to '%#' %lu", path, (unsigned long)array.count);
NSMutableDictionary * rootObject;
rootObject = [NSMutableDictionary dictionary];
[rootObject setValue:array forKey:#"alarms"];
[NSKeyedArchiver archiveRootObject:rootObject toFile:path];
}
-(void)loadDataFromDisk
{
NSString *path = [self pathForDataFile];
NSDictionary *rootObject = [NSMutableDictionary dictionary];
rootObject = [NSKeyedUnarchiver unarchiveObjectWithFile:path];
// "array" is an array with Objects of "Alarm"
array = [rootObject valueForKey:#"alarms"];
NSLog(#"Loaded from : %# %lu",path ,(unsigned long)array.count);
}
I hope anyone can help me out with this.
Thanks in advance.
You #synthized the array backing store (ivar) as _array. So you need to access the array as either _array or self.array. In saveDataToDisk and loadDataFromDisk it is accessed as array.
To test your array coding try something simple like this:
NSLog(#"array: %#", self.array);
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:self.array];
NSLog(#"data: %#", data);
NSArray *recovered = [NSKeyedUnarchiver unarchiveObjectWithData:data];
NSLog(#"recovered: %#", recovered);
Note: There is no need to wrap your array in a NSMutableDictionary.
When that works change it to the file based method calls.
Check that the filePath is valid.
Check that the file is created.
Check that the file contents are the same as in the above test code.
Note: There is no reason to wrap your array in a NSMutableDictionary.
Okay I've been trying at this for about 2-3 hours now and I don't seem to quite get it. Here is the code and a brief explanation:
I'm trying to make two lists of words, pull one word from each of those lists at random, and display both words (along with a third) on the screen when a button is pressed. Here is the code:
#import "Project001ViewController.h"
#implementation Project001ViewController
-(ArrayOfWords *) advs
{
if(!advs){
advs = [[ArrayOfWords alloc] init];
NSString* advpath = #"/WordLists/adverbs.txt";
NSLog(#"1");
[[self advs] populateListOfWords:advpath];
}
return advs;
}
-(ArrayOfWords *) adjs
{
if (!adjs) {
adjs = [[ArrayOfWords alloc] init];
NSString* adjpath = #"/WordLists/adjectives.txt";
[[self adjs] populateListOfWords:adjpath];
NSLog(#"2");
}
return adjs;
}
- (IBAction)generate:(UIButton *)sender;
{
//int randy = arc4random() % 11;
//NSNumber* num= [NSNumber numberWithInteger:randy];
NSString* obj = #"app";
NSString* adverb = [[self advs] randomItem];
NSString* adjective = [[self adjs] randomItem];
NSLog(#"%i %i",[adjs size],[advs size]);
NSLog(#"1 %# %# %#.",adverb, adjective, obj);
//NSLog(#"%#",thePhrase);
[display setText:#"Hi"];
}
#end
I'm having trouble on the last NSLog line:
NSString* obj = #"app";
NSString* adverb = [[self advs] randomItem];
NSString* adjective = [[self adjs] randomItem];
NSLog(#"%i %i",[adjs size],[advs size]);
NSLog(#"1 %# %# %#.",adverb, adjective, obj);
Instead of getting the two randomly selected words (using arc4random() to produce them) the array returns Null. But I know FOR CERTAIN. That the array's are not empty because the NSLog Line where I print [adjs size] and [advs size] I get the correct sizes of the list of words. I just want to know what is causing them to print Null here.
populateListOfWords, randomItem, and size methods:
- (NSArray *) populateListOfWords:(NSString *) path {
//gets the components of the file into an NSString
NSString *wordListString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil];
//returns an array of all the words (uses the next line indicator '\n' to know when it's at the end of the word
NSArray* words = [wordListString componentsSeparatedByString:#"\n"];
length=(NSNumber*)([words count]);
return words;
}
-(NSString*) randomItem{
//returns random object in list
return (NSString*)[list objectAtIndex:(arc4random() % (int)length)] ;
}
-(int) size{
//returns size of list
return (int)length;
}
(If more code is needed let me know and thank you in advanced for any and all help).
I believe there is a problem with the paths. It is impossible to have access to the path /WordLists/adjectives.txt in iOS due to the application sandbox. I suggest you add these files to the application by dragging and dropping them onto the project. You can get the file paths for resources in application bundle using
NSString * path = [[NSBundle mainBundle] pathForResource:#"adjectives" ofType:#"txt"];
Now pass this path to the method populateListOfWords:.
Because of the incorrect path, I believe wordListString is nil and everything else follows to be that.
Another thing is that int and NSNumber are not toll free bridged like NSStrings and other foundation objects. So
length=(NSNumber*)([words count]);
is incorrect. I suggest you define length as int or better NSUInteger to match the type count method returns.
This method is the problem:
- (NSArray *) populateListOfWords:(NSString *) path {
//gets the components of the file into an NSString
NSString *wordListString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil];
//returns an array of all the words (uses the next line indicator '\n' to know when it's at the end of the word
NSArray* words = [wordListString componentsSeparatedByString:#"\n"];
length=(NSNumber*)([words count]);
return words;
}
It wasn't actually putting the words in a list that anyone else could access. I had to just modify it like so:
- (void) populateListOfWords:(NSString *) path {
//gets the components of the file into an NSString
NSString *wordListString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil];
//returns an array of all the words (uses the next line indicator '\n' to know when it's at the end of the word
NSArray* words = [wordListString componentsSeparatedByString:#"\n"];
list = words;
length=(int)([words count]);
}
Now it gives me the correct output. But for some reason when I press the button twice it crashes. Oh well that's a new problem. Thanks again for all the help.
UPDATE
Turns out advs and adjs were being released so the second go around it was trying to access a nil value because when I call [self advs] [self adjs] the pointers exist, but their contents do not. I had to go back and refill them each time basically removing the if (!advs) and if (adjs) parts. It now works as intended.
I had a method to save a dic to the disk:
+(BOOL) writeApplicationData:(NSDictionary *)data
bwriteFileName:(NSString *)fileName
{
NSLog(#"writeApplicationData");
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
if (!documentsDirectory) {
NSLog(#"Documents directory not found!");
return NO;
}
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:fileName];
return ([data writeToFile:appFile atomically:YES]);
}
And I tested it with:
NSMutableDictionary *dic = [[NSMutableDictionary alloc] init];
NSMutableDictionary *d1 = [[NSMutableDictionary alloc] init];
NSMutableDictionary *d2 = [[NSMutableDictionary alloc] init];
[d1 setObject:#"d11"
forKey:#"d11"];
[d1 setObject:#"d12"
forKey:#"d12"];
[d1 setObject:#"d13"
forKey:#"d13"];
[d2 setObject:#"d21"
forKey:#"d21"];
[d2 setObject:#"d22"
forKey:#"d22"];
[d2 setObject:#"d23"
forKey:#"d23"];
[dic setObject:d1
forKey:#"d1"];
[dic setObject:d2
forKey:#"d2"];
[self writeApplicationData:dic
bwriteFileName:#"testSave"];
And the data is saved correctly.
Then I tried to save d1 with class obj in it:
LevelInfoData *levelInfoData = [[LevelInfoData alloc] init];
[levelInfoDictionary setObject:levelInfoData
forKey:#"test"];
[dic setObject:levelInfoDictionary
forKey:#"LevelInfoDictionary"];
But this time, even no plist file was generated in the disk.
Here is the LevelInfoData class:
#interface LevelInfoData : NSObject {
int levelNum;
}
#property (nonatomic) int levelNum;
#end
#implementation LevelInfoData
#synthesize levelNum;
#synthesize isLevelLocked;
#synthesize isLevelCleared;
#synthesize levelHighScore;
-(id)init
{
if( (self = [super init]) ) {
levelNum = 0;
}
return self;
}
#end
I'm really confused, hope somebody could help me out, thanks.
The contents of the dictionary need to be property list type objects.
From the NSDictionary Class Reference:
This method recursively validates that all the contained objects are property list objects (instances of NSData, NSDate, NSNumber, NSString, NSArray, or NSDictionary) before writing out the file, and returns NO if all the objects are not property list objects, since the resultant file would not be a valid property list.
https://developer.apple.com/library/ios/#documentation/Cocoa/Reference/Foundation/Classes/NSDictionary_Class/Reference/Reference.html
You may want to try making your custom class a subclass of NSData rather than NSObject.
I'm not sure how attached you are to NSDictionary, but this may be a situation where NSCoder will better serve you.
See nscoder vs nsdictionary when do you use what
More details here:
NSCoder Class Reference
Some code snippets
A tutorial
I have a function which use for read one single line from a csv file.
But I got a release of previously deallocated object error, or sometimes the it is "double free" error.
I try to track down which object causes this error base on the error memory address, but I failed to do this.
Here's the code:
#interface CSVParser : NSObject {
NSString *fileName;
NSString *filePath;
NSString *tempFileName;
NSString *tempFilePath;
//ReadLine control
BOOL isFirstTimeLoadFile;
NSString *remainContent;
}
#property(nonatomic,retain) NSString *fileName;
#property(nonatomic,retain) NSString *filePath;
#property(nonatomic,retain) NSString *tempFileName;
#property(nonatomic,retain) NSString *tempFilePath;
#property(nonatomic,retain) NSString *remainContent;
-(id)initWithFileName:(NSString*)filename;
-(BOOL)checkAndCopyFile:(NSString *)filename;
-(BOOL)checkAndDeleteTempFile;
-(NSString*)readLine;
-(NSArray*)breakLine:(NSString*)line;
#end
#implementation CSVParser
#synthesize fileName;
#synthesize filePath;
#synthesize tempFileName;
#synthesize tempFilePath;
#synthesize remainContent;
-(id)initWithFileName:(NSString *)filename{
//ReadLine control
isFirstTimeLoadFile = TRUE;
self.fileName = filename;
self.tempFileName = [[NSString alloc] initWithFormat:#"temp_%#",fileName];
NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentDir = [documentPaths objectAtIndex:0];
self.filePath = [documentDir stringByAppendingPathComponent:fileName];
self.tempFilePath = [documentDir stringByAppendingPathComponent:tempFileName];
if ([self checkAndCopyFile:fileName]) {
return self;
}else {
return #"Init Failure";
}
}
-(BOOL)checkAndCopyFile:(NSString *)filename{
BOOL isFileExist;
NSError *error = nil;
NSFileManager *fileManger = [NSFileManager defaultManager];
isFileExist = [fileManger fileExistsAtPath:filePath];
if (isFileExist) {
//Create a temp file for reading the line.
[fileManger copyItemAtPath:filePath toPath:tempFilePath error:&error];
return TRUE;
}else {
return FALSE;
}
}
-(NSString*)readLine{
NSError *error = nil;
//Read the csv file and save it as a string
NSString *tempFirstLine = [[[NSString alloc] init] autorelease];
NSString *stringFromFileAtPath = [[NSString alloc] init];
if (isFirstTimeLoadFile) {
NSLog(#"Into First Time");
stringFromFileAtPath = [NSString stringWithContentsOfFile:tempFilePath
encoding:NSUTF8StringEncoding
error:&error];
isFirstTimeLoadFile = FALSE;
}else {
NSLog(#"Not First Time");
NSLog(#"Not First Time count:%d",[remainContent retainCount]);
stringFromFileAtPath = remainContent;
remainContent = nil;
}
if ([stringFromFileAtPath isEqualToString:#""]) {
[stringFromFileAtPath release];
return #"EOF";
}
//Get the first line's range
NSRange firstLineRange = [stringFromFileAtPath rangeOfString:#"\n"];
//Create a new range for deletion. This range's lenght is bigger than the first line by 1.(Including the \n)
NSRange firstLineChangeLineIncludedRange;
if (stringFromFileAtPath.length > 0 && firstLineRange.length == 0) {
//This is the final line.
firstLineRange.length = stringFromFileAtPath.length;
firstLineRange.location = 0;
firstLineChangeLineIncludedRange = firstLineRange;
}else {
firstLineRange.length = firstLineRange.location;
firstLineRange.location = 0;
firstLineChangeLineIncludedRange.location = firstLineRange.location;
firstLineChangeLineIncludedRange.length = firstLineRange.length + 1;
}
//Get the first line's content
tempFirstLine = [stringFromFileAtPath substringWithRange:firstLineRange];
remainContent = [stringFromFileAtPath stringByReplacingCharactersInRange:firstLineChangeLineIncludedRange withString:#""];
[stringFromFileAtPath release];
error = nil;
return tempFirstLine;
}
And the following code shows how I use the class above:
CSVParser *csvParser = [[CSVParser alloc] initWithFileName:#"test.csv"];
BOOL isFinalLine = FALSE;
while (!isFinalLine) {
NSString *line = [[NSString alloc] init];
line = [csvParser readLine];
if ([line isEqualToString:#"EOF"]) {
isFinalLine = TRUE;
}
NSLog(#"%#",line);
[line release];
}
[csvParser release];
If I run the code, and finish the csv parsing, the App's main function will give me the double free error when it try to free the autorelease pool."* __NSAutoreleaseFreedObject(): release of previously deallocated object (0x6a26050) ignored"
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
int retVal = UIApplicationMain(argc, argv, nil, nil);
Could someone help me solve this issue?
Thank you!
[pool release];
Do not use -retainCount.
The absolute retain count of an object is meaningless.
You should call release exactly same number of times that you caused the object to be retained. No less (unless you like leaks) and, certainly, no more (unless you like crashes).
See the Memory Management Guidelines for full details.
There are a few problems in your code:
you aren't following the correct init pattern. You should have a self = [super init...]; if (self) {...} in there somewhere.
tempFileName is a retain property and you assign it the result of alloc/init. It will be leaked.
An immutable empty string ([[NSString alloc] init]) is pretty much never useful. And, in fact, stringFromFileAtPath is being leaked (technically -- implementation detail wise there is an empty immutable singleton string and thus, no real leak, but.... still...)
Finally, the crash: your readLine method correctly returns an autoreleased object. Yet, your while() loop consuming the return value of readLine is also releaseing that return value, leading to a double-release and an attempt to free that which was already freed.
You should "build and analyze" your code. I bet the llvm static analyzer would identify most, if not all, of the problems I mentioned above (and probably some more I missed).
When building with the analyzer, do you have either "all messages" or "analyzer issues only" selected in the Build window? Because, looking at the code, I'm surprised the analyzer didn't catch the obvious problem with stringFromFileAtPath.
Excerpting the code, you have the following lines that manipulate stringFromFileAtPath:
NSString *stringFromFileAtPath = [[NSString alloc] init];
....
stringFromFileAtPath = [NSString stringWithContentsOfFile:tempFilePath
encoding:NSUTF8StringEncoding
error:&error];
....
stringFromFileAtPath = remainContent;
....
[stringFromFileAtPath release];
And remainContent is set by:
remainContent = [stringFromFileAtPath stringByReplacingCharactersInRange:firstLineChangeLineIncludedRange
withString:#""];
You are releasing an autoreleased object. By memory keeps going up, how are you measuring it? Don't use Activity Monitor as it is nearly as useless to developers as retainCount is misleading. Use Instruments.
Your tempFirstLine NSString object is declared with autorelease, and is returned as your NSString line, which is then released.
Try using this:
while (!isFinalLine) {
NSString *line = [csvParser readLine];
if ([line isEqualToString:#"EOF"]) {
isFinalLine = TRUE;
}
NSLog(#"%#",line);
}
Replac this:
NSString *stringFromFileAtPath = [[NSString alloc] init];
with this:
NSString *stringFromFileAtPath = nil;
and get rid of the [stringFromFileAtPath release] statements.
The first line creates a pointer to a new string object that you never use, because you immediately overwrite the pointer with a pointer to string objects from elsewhere, which you don't need to release because you don't own them/didn't create them. Since you are releasing them, you're getting a crash.
You make the same mistake with tempFirstLine.