I think you are missing to allocate the memory for array. So try this NSMutableArray *randomSelection = [[NSMutableArray alloc] init]; [randomSelection addObject:@”string1″]; NSString *test = [randomSelection objectAtIndex:0]; NSLog(test);
Here are two options: – (NSMutableArray *)createMutableArray1:(NSArray *)array { return [NSMutableArray arrayWithArray:array]; } – (NSMutableArray *)createMutableArray2:(NSArray *)array { return [[array mutableCopy] autorelease]; }
Use -insertObject:atIndex: or replaceObjectAtIndex:withObject:.
If you’re loading objects from a database and you know exactly how many objects you have, you would likely get the best performance from NSMutableArrays arrayWithCapacity: method, and adding objects to it until full, so it allocates all the memory at once if it can. Behind the scenes, they’re secretly the same thing – NSArray … Read more
NSMutableArray *myArray = [NSMutableArray array]; for(int i = 0; i < 10; i++) { [myArray addObject:@(i)]; } NSLog(@”myArray:\n%@”, myArray);
If every element in the array is a dictionary containing a certain key, you can sort the array using a sort descriptor. For instance, if every element is a dictionary containing a key called “name”: NSSortDescriptor *sortByName = [NSSortDescriptor sortDescriptorWithKey:@”name” ascending:YES]; NSArray *sortDescriptors = [NSArray arrayWithObject:sortByName]; NSArray *sortedArray = [array sortedArrayUsingDescriptors:sortDescriptors];
For adding subject to the email using UIActivityViewController on iOS6, this is the best solution that anyone can use.. All you have to do is call the following while initializing UIActivityViewController. UIActivityViewController *activityViewController = [[UIActivityViewController alloc] initWithActivityItems:activityItems applicationActivities:applicationActivities]; [activityViewController setValue:@”My Subject Text” forKey:@”subject”]; And your UIActivityViewController is populated with a subject.
cell.titleLabel.text = txn.funcCdDscp; cell.totalCountLabel.text = txn.taskCount; One of these (not sure which, but my guess would be taskCount) is a NSNumber. Text takes an NSString.
Simply use; NSArray* reversed = [[myArray reverseObjectEnumerator] allObjects]; The order is documented to be correct: This array contains all the remaining objects of the enumerator in enumerated order [emphasis added].
To get the number of objects in the array, use [temp count] If you want the total memory usage of the array, you’ll have to loop through and add up how much memory each object uses, but I don’t think that a generic object will give you its size. In general, you shouldn’t really have … Read more