I am relatively new to Xcode and am trying to write an app that will play a video from iTunes from a tutorial but my app keeps crashing.
It is giving me the error code:
'NSInvalidArgumentException', reason: '* -[__NSArrayM insertObject:atIndex:]: object cannot be nil'
I used breakpoints and found where the problem is but I'm not sure how to fix it. The line that is giving me problems is:
[list addObject:[item valueForProperty:MPMediaItemPropertyAssetURL]];
Does anyone have any ideas? Below is the .m file code:
#implementation iPodLibrary
+(NSArray *) movieList {
NSMutableArray *list =
[[[NSMutableArray allocWithZone:NULL] init] autorelease];
MPMediaQuery *query = [[MPMediaQuery alloc] init];
[query addFilterPredicate:[MPMediaPropertyPredicate
predicateWithValue:[NSNumber numberWithInteger:(MPMediaTypeAny ^ MPMediaTypeAnyAudio)]
forProperty:MPMediaItemPropertyMediaType]];
for (MPMediaItem* item in [query items]) {
[list addObject:[item valueForProperty:MPMediaItemPropertyAssetURL]];
}
[query release];
return list;
}
+ (NSString *) movieTitle:(NSURL *)aURL {
NSString *aTitle = nil;
if (aURL) {
AVAsset* aAsset = [[AVURLAsset allocWithZone:NULL]
initWithURL:aURL options:nil];
for (AVMetadataItem* metadata in [aAsset commonMetadata]) {
if ([[metadata commonKey] isEqualToString:AVMetadataCommonKeyTitle]) {
aTitle = [metadata stringValue];
break;
}
}
}
return aTitle;
}
#end
Check that [item valueForProperty:MPMediaItemPropertyAssetURL] is actually returning a value. NSMutableArray does not allow the addition of a nil value with the addObject method. See NSMutableArray addObject: documentation
You can check if it is null like so:
for (MPMediaItem* item in [query items]) {
id itemValue = [item valueForProperty:MPMediaItemPropertyAssetURL];
[list addObject:itemValue]; // break point this line and see what itemValue is.
}
In Objective C you cannot put nil values into NSArray or NSDictionary.
Related
Im working with a singleton to store some data, her's the implementation
static ApplicationData *sharedData = nil;
#implementation ApplicationData
#synthesize list;
+ (id)sharedData
{
static dispatch_once_t dis;
dispatch_once(&dis, ^{
if (sharedData == nil) sharedData = [[self alloc] init];
});
return sharedData;
}
- (id)init
{
if (self = [super init])
{
list = [[NSMutableArray alloc]init];
}
return self;
}
if list have less than 3 (2<) object i the app crash with "index 0 beyond bounds for empty array"
// NSMutableArray *anArray = [[NSMutableArray alloc]initWithObjects:#"", nil];
while ([[[ApplicationData sharedData]list] lastObject] != nil)
{
File *file = [[[ApplicationData sharedData]list] lastObject];
BOOL isDir;
if (![[NSFileManager defaultManager] fileExistsAtPath:file.filePath isDirectory:&isDir])
{
NSMutableDictionary *tmpDic = [NSMutableDictionary dictionaryWithObjects:[NSArray arrayWithObjects:file.fileName,file.filePath,logEnteryErrorfileNotFoundDisplayName,[formatter stringFromDate:[NSDate date]], nil] forKeys:[NSArray arrayWithObjects:logShredFileName,logShredFilePath,logShredStatue,logShredDate, nil]];
[logArray addObject:tmpDic];
errorOccured = YES;
[[[ApplicationData sharedData]list] removeLastObject];
continue;
}
... other code
}
if i use the anArray that work perfectly.
what is the problem ?
That's totally weird, you've probably did something else to achieve this. Why don't you use - (void)removeAllObjects?
Maybe you remove objects in the while cycle the last line, ie:
while ([[[ApplicationData sharedData]list] count] != 0)
{
// remove object from list
// ...
[[[ApplicationData sharedData]list] removeLastObject];
}
And just a note, you don't need to check if (sharedData == nil) in sharedData as far as it's guaranteed to be executed only once. (unless you do something outside to your static variable, but that's not how it's supposed to be done I believe)
This question already has an answer here:
Closed 10 years ago.
Possible Duplicate:
'isMemberOfClass' returning 'NO' when custom init
I've some trouble with the "isMemberOfClass"-Method.
I have a class, that generates and returns objects ("MyObject")
// ObjectFactory.h
...
-(MyObject*)generateMyObject;
...
// ObjectFactory.m
...
-(MyObject*)generateMyObject
{
MyObject *obj = [[MyObject alloc]init];
obj.name = #"Whatever"; // set properties of object
return obj;
}
...
And there's a unittest-class, that calls the generateMyObject-selector and checks the class of the returned object:
...
ObjectFactory *factory = [[ObjectFactory alloc]init];
MyObject *obj = [factory generateMyObject];
if (![obj isMemeberOfclass:[MyObject class]])
STFail(#"Upps, object of wrong class returned...");
else
...
I expect, that the else-part is processed...but the STFail(...) is called instead, but why?
Thx for any help!
Regards,
matrau
Ok, here is the original copy&pasted code:
//testcase
- (void)test001_setCostumeFirstCostume
{
NSString *xmlString = #"<Bricks.SetCostumeBrick><costumeData reference=\"../../../../../costumeDataList/Common.CostumeData\"/><sprite reference=\"../../../../..\"/></Bricks.SetCostumeBrick>";
NSError *error;
NSData *xmlData = [xmlString dataUsingEncoding:NSASCIIStringEncoding];
GDataXMLDocument *doc = [[GDataXMLDocument alloc] initWithData:xmlData
options:0 error:&error];
SetCostumeBrick *newBrick = [self.parser loadSetCostumeBrick:doc.rootElement];
if (![newBrick isMemberOfClass:[SetCostumeBrick class]])
STFail(#"Wrong class-member");
}
// "MyObject"
#implementation SetCostumeBrick
#synthesize indexOfCostumeInArray = _indexOfCostumeInArray;
- (void)performOnSprite:(Sprite *)sprite fromScript:(Script*)script
{
NSLog(#"Performing: %#", self.description);
[sprite performSelectorOnMainThread:#selector(changeCostume:) withObject:self.indexOfCostumeInArray waitUntilDone:true];
}
- (NSString*)description
{
return [NSString stringWithFormat:#"SetCostumeBrick (CostumeIndex: %d)", self.indexOfCostumeInArray.intValue];
}
#end
// superclass of SetCostumeBrick
#implementation Brick
- (NSString*)description
{
return #"Brick (NO SPECIFIC DESCRIPTION GIVEN! OVERRIDE THE DESCRIPTION METHOD!";
}
//abstract method (!!!)
- (void)performOnSprite:(Sprite *)sprite fromScript:(Script*)script
{
#throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:#"You must override %# in a subclass", NSStringFromSelector(_cmd)]
userInfo:nil];
}
#end
// the "factory" (a xml-parser)
- (SetCostumeBrick*)loadSetCostumeBrick:(GDataXMLElement*)gDataSetCostumeBrick
{
SetCostumeBrick *ret = [[SetCostumeBrick alloc] init];
NSArray *references = [gDataSetCostumeBrick elementsForName:#"costumeData"];
GDataXMLNode *temp = [(GDataXMLElement*)[references objectAtIndex:0]attributeForName:#"reference"];
NSString *referencePath = temp.stringValue;
if ([referencePath length] > 2)
{
if([referencePath hasSuffix:#"]"]) //index found
{
NSString *indexString = [referencePath substringWithRange:NSMakeRange([referencePath length]-2, 1)];
ret.indexOfCostumeInArray = [NSNumber numberWithInt:indexString.intValue-1];
}
else
{
ret.indexOfCostumeInArray = [NSNumber numberWithInt:0];
}
}
else
{
ret.indexOfCostumeInArray = nil;
#throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:#"Parser error! (#1)"]
userInfo:nil];
}
NSLog(#"Index: %#, Reference: %#", ret.indexOfCostumeInArray, [references objectAtIndex:0]);
return ret;
}
SOLUTION:
Eiko/jrturton gave me a link to the solution - thx: isMemberOfClass returns no when ViewController is instantiated from UIStoryboard
The problem was, that the classes were included in both targets (app and test bundle)
Thank you guys for your help :)
You generally want isKindOfClass:, not isMemberOfClass. The isKindOfClass: will return YES if the receiver is a member of a subclass of the class in question, whereas isMemberOfClass: will return NO in the same case.
if ([obj isKindOfClass:[MyObject class]])
For example,
NSArray *array = [NSArray array];
Here [array isMemberOfClass:[NSArray class]] will return NO but [array isKindOfClass:[NSArray class]] will return YES.
Ok, with different class addresses per your comment, I think I can track this down to be a duplicate of this:
isMemberOfClass returns no when ViewController is instantiated from UIStoryboard
Basically, your class is included twice.
i have started to integrate core data in my current project and it is the first time i work with it.
i have managed to write new objects into my NSManagedObjectContext and read them out. my problem is, that after closing the app all objects are lost. here is one of the functions that adds new objects:
-(void)addExpenseWithValue:(NSNumber *)value name:(NSString *)name type:(BOOL)type andDate:(NSDate *)date{
//get the right managed object context
NSManagedObjectContext *context = self.managedObjectContext;
//creat a new expense in context
NSManagedObject *newExpense = [NSEntityDescription insertNewObjectForEntityForName:#"Expense" inManagedObjectContext:context];
//Get Number representation of month and year
NSNumber *monthNumber = [self getMonthNumber:date];
NSNumber *dayNumber = [self getDayNumber:date];
//set values of the expense
[newExpense setValue:[NSDate date] forKey:#"date"];
[newExpense setValue:value forKey:#"value"];
[newExpense setValue:name forKey:#"name"];
[newExpense setValue:[NSNumber numberWithBool:type ] forKey:#"expenseType"];
[newExpense setValue:monthNumber forKey:#"month"];
[newExpense setValue:dayNumber forKey:#"day"];
[self storeData];
}
-(void)storeData{
NSError *error = nil;
[managedObjectContext save:&error];
}
the objects are actually stored and i can read them out afterwards. as far as i know it has something to do with the persistentStore and persistentStoreCoordinator. my appDelegate has the following methods implemented:
- (NSPersistentStoreCoordinator *)persistentStoreCoordinator {
if (persistentStoreCoordinator != nil) {
return persistentStoreCoordinator;
}
NSURL *storeUrl = [NSURL fileURLWithPath: [[self applicationDocumentsDirectory]
stringByAppendingPathComponent: #"<Project Name>.sqlite"]];
NSError *error = nil;
persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc]
initWithManagedObjectModel:[self managedObjectModel]];
if(![persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType
configuration:nil URL:storeUrl options:nil error:&error]) {
/*Error for store creation should be handled in here*/
}
return persistentStoreCoordinator;
}
- (NSManagedObjectContext *) managedObjectContext {
if (managedObjectContext != nil) {
return managedObjectContext;
}
NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
if (coordinator != nil) {
managedObjectContext = [[NSManagedObjectContext alloc] init];
[managedObjectContext setPersistentStoreCoordinator: coordinator];
}
return managedObjectContext;
}
- (NSManagedObjectModel *)managedObjectModel {
if (managedObjectModel != nil) {
return managedObjectModel;
}
managedObjectModel = [NSManagedObjectModel mergedModelFromBundles:nil] ;
return managedObjectModel;
}
- (NSString *)applicationDocumentsDirectory {
return [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
}
UPDATE:
i have added a small testfunction, to experiment it gets called in the first viewController:
-(void)test{
NSArray* stores = [[managedObjectContext persistentStoreCoordinator]persistentStores];
if ([stores objectAtIndex:0]==nil) {
NSLog(#"no stores found");
}
else
NSLog(#"%d", [stores count]);
}
managedObjectContext is the applications NSanagedObjectContext as initiated in the appdelegate. it exists, the array gets allocated, but the count stays at 0.
2012-03-06 20:09:37.772 DailyBudget[1533:fb03] *** Terminating app due to uncaught
exception 'NSRangeException', reason: '*** -[__NSArrayI objectAtIndex:]: index 0 beyond
bounds for empty array'
*** First throw call stack:
(0x135f052 0x174fd0a 0x134b674 0x3c6a 0x3894 0x46cfbf 0x46d21b 0x4838b1 0x46cfbf
0x46d21b 0x46e0f1 0x3dcfec 0x3e2572 0x3dc72b 0x3cbbc2 0x3cbce2 0x3cbea8 0x3d2d9a 0x25b3
0x3a39d6 0x3a48a6 0x3b3743 0x3b41f8 0x3a7aa9 0x1f57fa9 0x13331c5 0x1298022 0x129690a
0x1295db4 0x1295ccb 0x3a42a7 0x3a5a9b 0x2488 0x23e5 0x1)
terminate called throwing an exception(gdb)
at the moment of the error i have the following objects:
what am i missing?
... 24 hours later. i was somehow able to solve it myself =)
i think the problem layed within the storeURL. my new code was inspired from this post here:
Adding CoreData to Existing Project (theappcodeblog.com)
thanks for your guys for checking it out anyways =)
new code (working):
NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:#"CoreDataTabBarTutorial.sqlite"];
with function
- (NSURL *)applicationDocumentsDirectory {
return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
}
I'm having problems with memory leaks with this function. I thought creating an NSArray with componentsSeparatedByString was autorelease but instruments seems to indicate a leak at the NSArray aPair. Why would it indicate a leak there and not also at the other NSArrays created in the same way?
-(void) checkRequest: (NSString *)request view:(UIViewController *)theView webView:(UIWebView *)wView
{
//NSLog(#"JSResponder - checkRequest()");
NSString *aRequest = [NSString stringWithString:request];
NSArray *urlArray = [aRequest componentsSeparatedByString:#"?"];
if([urlArray count] > 1)
{
NSString *paramsString = [urlArray lastObject];
NSString *cmd = #"";
NSArray *urlParamsArray = [paramsString componentsSeparatedByString:#"&"];
int numCommands = [urlParamsArray count];
NSMutableDictionary *paramsWithNames = [[NSMutableDictionary alloc ] initWithCapacity:numCommands];
for (NSString *elementPair in urlParamsArray)
{
NSArray *aPair = [elementPair componentsSeparatedByString:#"="];
NSString *aKey = [aPair objectAtIndex:0];
NSString *aParam = [aPair objectAtIndex:1];
if([aKey compare:#"_command"] == NSOrderedSame)
{
cmd = aParam;
}
else
{
[paramsWithNames setValue: aParam forKey:aKey];
}
}
[self executeCommand: cmd withParams: paramsWithNames view:theView webView:wView];
[paramsWithNames release];
}
}
This function get called by the following:
- (void)pullJSEvent:(NSTimer*)theTimer
{
NSLog(#"MainView - pullJSEvent()");
NSString *jsCall = [NSString stringWithString:#"if(typeof checkOBJCEvents == 'function'){checkOBJCEvents();}"];
NSString *jsAnswer = [[webView stringByEvaluatingJavaScriptFromString:jsCall] retain];
if([jsAnswer compare:#"none"] != NSOrderedSame)
{
//NSLog(#" answer => %#", jsAnswer);
[jsResponder checkRequest:jsAnswer view:(UIViewController *)self webView:self.webView];
}
[jsAnswer release];
}
Thank-you
You're going to have to dig a bit deeper with the Leaks instrument. You're leaking one of the strings in the array, not the array itself. Leaks indicates that line because that's where the strings in the array are allocated.
Go into Leaks, look at a leaked instance, and click that little arrow button. You'll see all the retains and releases of the leaked object, which should point you to the problem.
I am relatively new to Objective-C and now I have a problem in my iPhone app that I don't fully understand.
I try to use a NSMutableDictionary, this does not seem to work as i expect for some reason. When I run the debugger and do po numberToCallerMap to see the dictionary, I get an exception. I have read the documentation for NSMutableDictionary on how to initialize it, but I can not see what I am doing wrong. Help and advice are appreciated. The variable causing me problem is numberToCallerMap, here is the relevant function:
- (void)setData:(NSString*)value{
[list release];
list = [[NSMutableArray alloc] init];
SBJSON *json = [[[SBJSON alloc] init] autorelease];
NSMutableDictionary* numberToCallerMap;
CallerInfo* caller;
NSDictionary* callerInfo;
#try {
NSArray *array = (NSArray*)[json objectWithString:value];
// reading all the items in the array one by one
numberToCallerMap = [NSMutableDictionary dictionary];
for (id *item in array) {
// if the item is NSDictionary (in this case ... different json file will probably have a different class)
NSDictionary *dict2 = (NSDictionary *) item;
CallInfo *data = [CallInfo alloc];
[data initFromDictionary:dict2];
callerInfo = (NSDictionary*)[dict2 valueForKey:#"caller"] ;
//Here, we want the phonenumber to be part of the CallerInfo object instead.
// It is sent from the server as part of the Call-object
NSString* number = (NSString*)[dict2 valueForKey:#"phoneNumber"];
[callerInfo setValue:number forKey:#"phoneNumber"];
caller = (CallerInfo*)[numberToCallerMap valueForKey:number];
if(caller == nil || [caller isKindOfClass:[NSNull class]]){
caller = [CallerInfo alloc];
[caller initFromDictionary:callerInfo];
[numberToCallerMap setValue:caller forKey:number];
[list insertObject:caller atIndex:0];
}
[caller addRecentCall:data];
}
}
#catch (NSException * e) {
[list release];
list = [[NSMutableArray alloc] init];
}
#finally {
[numberToCallerMap release];
}
}
This is probably not the only problem, but you are not alloc-ing your numberToCallerMap dictionary, you are getting it from a convenience class method -- [NSMutableDictionary dictionary] -- that returns it autoreleased. So you should not call release on it yourself.