nsmutablearray

问题 Does anyone have advice on how to best initialize an NSMutableArray when it comes to dictating the capacity? The documentation mentions that "...even though you specify a size when you create an array, the specified size is regarded as a “hint”; the actual size of the array is still 0." So... 1) If I init with a greater capacity than I typically use, do I not have to worry about wasted memory? 2) If I init with a capacity typically lower than what I use, do I have to worry about heavier

问题 Does anyone have advice on how to best initialize an NSMutableArray when it comes to dictating the capacity? The documentation mentions that "...even though you specify a size when you create an array, the specified size is regarded as a “hint”; the actual size of the array is still 0." So... 1) If I init with a greater capacity than I typically use, do I not have to worry about wasted memory? 2) If I init with a capacity typically lower than what I use, do I have to worry about heavier

问题 I have two NSMutableArray 's. They consist of images or text. The arrays are displayed via a UITableView . When I kill the app the data within the UITableView gets lost. How to save array in UITableView by using NSUserDefault ? 回答1: Note: NSUserDefaults will always return an immutable version of the object you pass in. To store the information: // Get the standardUserDefaults object, store your UITableView data array against a key, synchronize the defaults NSUserDefaults *userDefaults =

问题 I have an issue persisting data in local storage for an NSMutableArray containing a list of NSStrings. I have a save method and a get method both appear to work when the app is running. However, once I close the app and restart the items in the array are gone. NSMutableArray*ImageTags; Get Data -(NSMutableArray*)GetDataNSMutableArray:(NSString*)ItemName { NSMutableArray *GetData = [[NSMutableArray alloc] init]; NSUserDefaults *currentDefaults = [NSUserDefaults standardUserDefaults]; NSData

问题 I'm struggling to pass a NSMutable array from a Modal View controller back to the view controller I came from. This is my current method: FirstViewController.h #import "SecondViewController.h" @property (strong, nonatomic) IBOutlet NSMutableArray *passedRecipientsArray; FirstViewController.m @synthesize passedRecipientsArray = _passedRecipientsArray; - (void)viewDidAppear:(BOOL)animated { NSLog(@"passedRecipientsArray: %@", self.passedRecipientsArray); } - (void)prepareForSegue:

问题 I have a UITableViewController which uses a NSMutableArray for it's datasource. The array is initially populated in the viewDidLoad method by calling a web service to retrieve the data and populate the NSMutableArray. The user then has the option to enter a search term (in a UISearchBar) and press Search to rerun the web service and repopulate the table list. At this point I need to empty the array and repopulate the table from the results of the web service. My question is what is the

问题 I have an NSString which is a mathematical expression. I have operators (+,-,*,/) and operands (digits from 0 to 9,integers,decimals etc) . I want to convert this NSString into NSArray . For example if my NSString is "7.9999-1.234*-9.21". I want NSArray having elements 7.9999,-,1.234,*,-,9.21 in the same order. How can I accomplish this? I have tried a code. It dosent work in all scenarios though. Here It is: code: NSString *str=@"7.9999-1.234*-9.21"; NSMutableArray *marray=[[NSMutableArray

问题 The following method: - (NSMutableArray*) timeSortedBegins { NSMutableArray* begins = [self.spans valueForKey: @"begin"]; NSSortDescriptor *sort = [[NSSortDescriptor alloc] initWithKey: @"cycleOffsetObject" ascending: YES]; [begins sortUsingDescriptors: @[sort]]; return begins; } throws this runtime exception: 2014-03-21 14:41:32.482 myValve[1741:60b] -[__NSArrayI sortUsingDescriptors:]: unrecognized selector sent to instance 0x16d7bc20 2014-03-21 14:41:32.484 myValve[1741:60b] ***

问题 NSMutableArray *tmpMutArr = [NSMutableArray arrayWithArray:allObjectsArray]; NSLog(@"The content of array is%@",tmpMutArr); int index; for (int i=0;i<[tmpMutArr count];i++) { if([[tmpMutArr objectAtIndex:i] isKindOfClass:[NSDictionary class]]) { NSMutableDictionary *tempDict = [tmpMutArr objectAtIndex:i]; if([[tempDict valueForKey:@"Name"] isEqualToString:[NSString stringWithFormat:@"%@", nameString]]) { index = i; } } } [tmpMutArr replaceObjectAtIndex:index withObject:[NSDictionary

问题 I have an NSMutableArray object that contains NSString objects. The mutable array object is called _usersToAddToFriendsList . When I am done adding NSString objects to it, I run the following code for Parse.com: [PFUser currentUser]; PFQuery *query = [PFQuery queryWithClassName:@"_User"]; [query whereKey:@"username" equalTo:_userSubmittedUsername]; [query getObjectInBackgroundWithId:_objectId block:^(PFObject *object, NSError *error) { object[@"friends"] = _usersToAddToFriendsList; [object