How can I sort or add an item to a UITableView the opposite way? - objective-c

Question

So, I have an UITableView which holds entries for an app I am making. The entriesViewController is its own class, with a .xib file. I have a button that adds a new item.
It does this with the following code:
-(IBAction)newItem:(id)sender {
LEItem *newItem = [[LEItemStore sharedStore] createItem];
NSLog(#"New Item = %#", newItem);
[TableView reloadData];
}
Now this works, and adds the item, however it puts it at the bottom of the list. Since this app logs things for days, I do not want the items in this order. The newest items should be placed at the top of the list. How do I do this? I didn't see any easy way to add items to the table view at the top, but I might be missing something pretty basic.
This doesn't seem like it should be hard, I am probably just overlooking something.
Ideas are welcome.
Edit:
Here is LEItem Store:
//
// LEItemStore.m
//
// Created by Josiah Bruner on 10/16/12.
// Copyright (c) 2012 Infinite Software Technologies. All rights reserved.
//
#import "LEItemStore.h"
#import "LEItem.h"
#implementation LEItemStore
+ (LEItemStore *)sharedStore
{
static LEItemStore *sharedStore = nil;
if (!sharedStore)
sharedStore = [[super allocWithZone:nil] init];
return sharedStore;
}
+ (id)allocWithZone:(NSZone *)zone
{
return [self sharedStore];
}
-(id)init
{
self = [super init];
if (self) {
NSString *path = [self itemArchivePath];
allItems = [NSKeyedUnarchiver unarchiveObjectWithFile:path];
if (!allItems)
{
allItems = [[NSMutableArray alloc] init];
}
}
return self;
}
- (NSArray * )allItems
{
return allItems;
}
-(LEItem *)createItem
{
LEItem *p = [LEItem addNewItem];
[allItems addObject:p];
return p;
}
- (void)removeItem:(LEItem *)p
{
[allItems removeObjectIdenticalTo:p];
}
-(void)moveItemAtIndex:(int)from toIndex:(int)to
{
if (from == to) {
return;
}
LEItem *p = [allItems objectAtIndex:from];
[allItems removeObjectAtIndex:from];
[allItems insertObject:p atIndex:to];
}
- (NSString *)itemArchivePath {
NSArray *documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentDirectory = [documentDirectories objectAtIndex:0];
return [documentDirectory stringByAppendingPathComponent:#"item.archive"];
}
-(BOOL)saveChanges {
NSString *path = [self itemArchivePath];
return [NSKeyedArchiver archiveRootObject:allItems toFile:path];
}
#end

Answer 1

It looks like the simplest solution would be to modify -[LEItemStore createItem] to this:
-(LEItem *)createItem {
LEItem *p = [LEItem addNewItem];
[allItems insertObject:p atIndex:0];
return p;
}

Answer 2

You can do it even without rearrange the array internally.If you implement the data source and you define this method:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath;
Assuming that in your array the oldest objects are at the lowest indexes,supposing that your table view has M rows, return a cell with the format of the object at index M-rowIndex-1.

Answer 3

Unless I'm missing something, after you create the new item, instead of using
[allItems addObject:p];
you just need:
[allItems insertObject:p atIndex:0];

Answer 4

Do you have any type of createdDate or other sortable property on the item? Simply sort your retained list of items (or NSFetchedResultsController) or whatever you are binding to by that property.

Answer 5

You can override the comparison mechanism in your LEItem class, and have it compare dates easily:
-(NSComparisonResult)compare:(LEItem*)otherItem {
return [self.dateCreated compare:otherItem.dateCreated];
}
Then, it's just a matter of using sortArrayUsingSelector: with the selector compare:.