I am trying to add an object to an array that is inside an array.
Here is my storyboard. Screen A is a simple tableView containing an array with object A, Screen B adds new objects to screen A. Each object A contains an array with detail (object B), these details are shown in screen C and you add details to object A in screen D.
So my model is as you can see above. I got Array A containing object A, each object contains Array B containing object B. Both my arrays are Mutable.
Object A = budget
Object B = item
I can not figure out how to add object B to array B.
- (void)addItemViewController:(AddItemViewController *)controller didFinishAddingItem:(Item *)item
int newRowIndex = [self.budgets.items count];
[self.dataModel.budgetsList addObjectFromArray:item];
NSLog(#"Item with name %# added", item.name);
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:newRowIndex inSection:0];
NSArray *indexPaths = [NSArray arrayWithObject:indexPath];
[self.tableView insertRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationAutomatic];
[self dismissViewControllerAnimated:YES completion:nil];
This is what I am doing so fare. My problem here is that I am adding item (object B) into budget array (array A). :/
Thanks in advance.
When you are doing this:
NSArray *indexPaths = [NSArray arrayWithObject:indexPath];
You are mixing Presentation with data. What you need here is get the object element (the array in your case) that this indexpath corresponds to. As per the Table view design pattern, every table view reads its cells from an underlying collection of data objects. Have you defined this object (most preferably in separate objective-c .m and .h files)?
As for adding array into another array, NSArray just expects NSObject as element, so it is pretty straight-forward to add one into another.
NSArray *arrayB = [[NSArray alloc] init]; //any other initialization is good as well
NSArray *arrayA= [NSArray arrayWithObject:arrayB];
The above code is valid for any pair of NSArrays in your code.
If you want to add an object to Array B, then Use:
[[[array A objectAtIndex:indexPath] arrayB] addObject:yourObject];
Or you can use (this is an expansion of above code):
ObjectA *temp = [array A objectAtIndex:indexPath];
NSMutableArray *tempArray = [temp arrayB];
[tempArray addObject:yourObject];
Cast your object B to Item then do
[self.dataModel.budgetList replaceObjectAtIndex:11 withObject:(Item)item];
This code assume that you want to replace the existing object inside A and the the index is 11. If you want to add you just use insertObjectAtIndex: withObject:
Related
I am having NSArray in which it is having following data, i am using AFHTTPRequestOperation which give me result and after that i am doing
[ListOfName addObject:[responseData valueForKey:name]]; and getting following result and that result i want to display in tableview but can understand how to do it becuause i an new to iphone
(
(
"Richard Conover",
"Richard Conover",
"Kaitlyn Matheson",
"Andrea Wannemaker",
"Andrea Wannemaker",
test,
james,
test,
gaurav,
sdfsdfs
)
)
if i do NSArray.count it will return only 1 so how to print it separately in tableview
What you want to do is set the TableView datasource to be the first object in that Array (which is another Array). Something like this:
NSArray *myTableViewDataSourceArray = [myOriginalArray objectAtIndex:0];
Then use myTableViewDataSourceArray for the datasource methods of the TableView.
As per your structure, you having array with objects which also array.
That means,[ListOfName addObject:[responseData valueForKey:name]]; will add array object. You try to load this array of data into your table view. So you can try this in your tableViewDataSource
- (NSInteger)numberOfSectionsInTableView:(UITableView *)aTableView
{
return [[ListOfName objectAtIndex:0] count];
}
It's a Nested Array (means Array inside Array).
Howmany Nested Arrays you have ?
If it's 1 then you can use :
NSArray *finalArray = [[NSArray alloc] initWithArray:[yourArray objectAtIndex:0]];
then you can use finalArray to populate the UITableView.
I'm having trouble making the sections in a UITableView. I've looked at the documentation for UILocalizedIndexedCollation as well as this sample code project:
https://developer.apple.com/library/ios/#samplecode/TableViewSuite/Listings/3_SimpleIndexedTableView_Classes_RootViewController_m.html#//apple_ref/doc/uid/DTS40007318-3_SimpleIndexedTableView_Classes_RootViewController_m-DontLinkElementID_18
What I have below is basically a straight copy/paste from the sample project. However, the sample project uses a custom object (TimeZoneWrapper.h) and then places the object in the correct section based on the object's instance variable (TimeZoneWrapper.localeName). However, I'm not using custom objects. I'm using just a bunch of regular NSStrings. So my question is what method on NSString should I pass to the #selector() to compare and place the string in the correct section array?
Currently, I'm calling NSString's copy method as a temporary hack to get things working (which it does), but I'm not sure if this is correct. A little explanation would be much appreciated!
- (void)configureSections {
// Get the current collation and keep a reference to it.
self.collation = [UILocalizedIndexedCollation currentCollation];
NSInteger index, sectionTitlesCount = [[collation sectionTitles] count]; // sectionTitles are A, B, C, etc.
NSMutableArray *newSectionsArray = [[NSMutableArray alloc] initWithCapacity:sectionTitlesCount];
// Set up the sections array: elements are mutable arrays that will contain the locations for that section.
for (index = 0; index < sectionTitlesCount; index++) {
NSMutableArray *array = [[NSMutableArray alloc] init];
[newSectionsArray addObject:array];
}
// Segregate the loctions into the appropriate arrays.
for (NSString *location in locationList) {
// Ask the collation which section number the location belongs in, based on its locale name.
NSInteger sectionNumber = [collation sectionForObject:location collationStringSelector:#selector(/* what do I put here? */)];
// Get the array for the section.
NSMutableArray *sectionLocations = [newSectionsArray objectAtIndex:sectionNumber];
// Add the location to the section.
[sectionLocations addObject:location];
}
// Now that all the data's in place, each section array needs to be sorted.
for (index = 0; index < sectionTitlesCount; index++) {
NSMutableArray *locationsArrayForSection = [newSectionsArray objectAtIndex:index];
// If the table view or its contents were editable, you would make a mutable copy here.
NSArray *sortedLocationsArrayForSection = [collation sortedArrayFromArray:locationsArrayForSection collationStringSelector:#selector(/* what do I put here */)];
// Replace the existing array with the sorted array.
[newSectionsArray replaceObjectAtIndex:index withObject:sortedLocationsArrayForSection];
}
self.sectionsArray = newSectionsArray;
}
Thanks in advance!
You should use #selector(self).
Using #selector(copy) will cause memory leaks in your project
I currently have a function written called saveWorkout that saves an NSMutableArray to another NSMutableArray from a Singleton class. This function works the first run through, however, when I run it a second time, it erases what was previously stored in element 0 and replaces it with the new array (which is a collection of strings gathered when a user clicks on a table).
Here is my function:
-(IBAction)saveWorkout{
WorkoutManager *workoutManager = [WorkoutManager sharedInstance];
[[workoutManager workouts] insertObject: customWorkout atIndex: 0];
NSLog(#"%#", [workoutManager workouts]);
}
customWorkout is what initialially creates the NSMutableArray (based on what the user clicks). Thus, if my first array is comprised of blah1, blah2, those two values will be stored in the workouts array. However, if I then click blah2, blah 3, the workouts array will have two identicle arrays (blah2, blah3) and it doesn't retain the first array. Any idea why this is happening?
Here is how I form customWorkout:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
NSString *str = cell.textLabel.text;
[customWorkout insertObject:str atIndex:0];
//Test Code: Prints Array
NSLog(#"%#", customWorkout);
}
I will tell you the logical mistake that you are making....
you are using the same customWorkout object over and over again to insert in the workouts array... (so its the same pointer) whereas what you need to do is to create a copy of the customWorkout array and then insert it in the workout array ... try this instead....
[[workoutManager workouts] insertObject: [[customWorkout mutableCopy] autorelease]atIndex: 0];
this should work unless you are doing something else in your code.
[[workoutManager workouts] insertObject: customWorkout atIndex: 0]; does not copy the contents of customWorkout ... instead it just retains a reference to customWorkout. So your code is simply storing multiple references to the same object, which you end up (unintentionally) editing on the second run through.
You need to either:
Copy the customWorkout object via copy when you store it in workouts
OR:
Assign customWorkout to a new NSMutableArray instance each time after you do a saveWorkout
Either route should keep you from modifying the NSMutableArray you store into the workouts collection. The first option is probably more clear in terms of memory-management...
I have to updates array values at position 2 and 4. How will I update array values. I am initializing my array like below.
ArrayrData=[[NSArray alloc]initWithArray:statuses]; // where statuses is also an array
You can't change the value of NSArray. So initialize your array as Mutable Array
NSMutableArray *ArrayrData=[[NSMutableArray alloc]init];
[ArrayrData addObjectsFromArray:statuses];
You can update the value in a NSMutableArray using,
– replaceObjectAtIndex:withObject:
– replaceObjectsAtIndexes:withObjects:
– replaceObjectsInRange:withObjectsFromArray:range:
– replaceObjectsInRange:withObjectsFromArray:
Use the method
- (void)replaceObjectAtIndex:(NSUInteger)index withObject:(id)anObject;
if u want to replace them with new objects or simply access the objects at index 2 and 4 and then modify them using
[ArrayrData objectAtIndex:idx]; //idx is the index of the object you want to access, in ur case it is 2 or 4.
You can change the NSMutableArray dynamically in the application as follows:
NSMutableArray *ArrayData = [[NSMutableArray alloc]init];
[ArrayData addObjectsFromArray:statuses];
And now whenever you want to replace any object in array then you can simply replace using the "replaceObjectAtIndex" method as follows:
[ArrayData replaceObjectAtIndex:2 withObject:#"your Object or data"];
[ArrayData replaceObjectAtIndex:4 withObject:#"your Object or data"];
Let me know if you have any questions.
Been searching for the answer to this for a while now and I think due to the nature of my array set up, I may be searching for the wrong answer!
I have a class which handles adding items to my array:
// Item.h
#interface Item : NSObject {
NSString *name;
NSNumber *seconds;
}
#property(nonatomic,copy) NSString *name;
#property(nonatomic,copy) NSNumber *seconds;
- (id)initWithName:(NSString *)n seconds:(NSNumber *)sec;
#end
and...
//item.m
#implementation Item
#synthesize name, seconds;
- (id)initWithName:(NSString *)n seconds:(NSNumber *)sec {
self.name = n;
self.seconds = sec;
return self;
}
#end
So to add an item, I use
Item *item1 = [[Item alloc] initWithName:#"runnerA" seconds:[NSNumber numberWithInt:780]];
I have some code which allows a user to edit a textfield (runner name) and the time which is a UIdatepicker set to hours and minutes. In the save method, that's working fine. It's the UPDATE that I cannot get to work. I've tried alsorts! Here's the code at the moment...
mainAppDelegate *appDelegate = (mainAppDelegate *)[[UIApplication sharedApplication] delegate];
Item *item = [[Item alloc] initWithName:inputName.text seconds:[NSNumber numberWithInt:secs]];
[appDelegate.arrItems replaceObjectAtIndex:rowBeingEdited withObject:item];
The above is simply adding a new item to the array (which is what I don't want). I'm not sure how to replace values. At the function, I have the row I need to update (rowBeingEdited) and the fields inputName.text and secs are both OK. (NSLog out confirms this).
How do I use the replaceObjectAtIndex to actually replace it with the values?! It's driving me mad now!!
Since you are simply trying to edit a particular row, why not use those property accessors that you already have set up in Item? It would look something like this:
Item *item = (Item *)[appDelegate.arrItems objectAtIndex:rowBeingEdited];
[item setName:inputName.text];
[item setSeconds:[NSNumber numberWithInt:secs]];
An a side note, are you using garbage collection, or do you manually release the Item objects that you create when adding items to the array? If you are doing it manually, it should look like this:
Item *item1 = [[Item alloc] initWithName:#"runnerA"
seconds:[NSNumber numberWithInt:780]];
[appDelegate.arrItems addObject:item1];
[item1 release];
This follows the rule of thumb: if you alloc, copy or retain anything, you must also release it. Note that this works because the array will retain the item when it is added.
Are you using NSArray or NSMutableArray?
Assuming you are using NSMutableArray, how did you initialize and populate the array in the first place?
For example, it's not enough to use -initWithCapacity: or +arrayWithCapacity: which only sets aside space. You have to use -addObject: for the first round of population, before you can use -replaceObjectAtIndex:withObject::
Note that NSArray objects are not like C arrays. That is, 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. This means that you cannot insert an object at an index greater than the current count of an array. For example, if an array contains two objects, its size is 2, so you can add objects at indices 0, 1, or 2. Index 3 is illegal and out of bounds; if you try to add an object at index 3 (when the size of the array is 2), NSMutableArray raises an exception.