sort data and display in UItableview on iphone - iphone

Question

i am using this query to get the data by ASC order
select * from list_tbl where cat_id=%d order by names ASC
now my table view shows data based on ASC order
then i used this to get the letters from A to Z on right side
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)help
{
return [[[UILocalizedIndexedCollation currentCollation] sectionTitles] objectAtIndex:help];
}
-(NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView
{
return [[UILocalizedIndexedCollation currentCollation] sectionIndexTitles];
}
- (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index
{
return [[UILocalizedIndexedCollation currentCollation] sectionForSectionIndexTitleAtIndex:index];
}
now my problem is how to divide data based on section header like all A content goes to A and then B till Z and when user click on any alphabet on right side it should goes to that section
// UPDATES ///////////////
-(void)setUpRecordsForIndexing
{
for (NSString * recordName in appDelegate.catLists)//where app.catList contains all the value
{
NSString *firstLetter = ([recordName length] ==0)?miscKey:[[recordName substringToIndex:1]uppercaseString];
/*if(![firstLetter beginsWithCharacterInSet:[NSCharacterSet letterCharacterSet]] || [recordName isEqualToString:#""] || recordName == nil )
firstLetter = miscKey ;
*/
NSMutableArray *indexArray = [IndexedRecords objectForKey:firstLetter];
if (indexArray == nil)
{
indexArray = [[NSMutableArray alloc] init];
[IndexedRecords setObject:indexArray forKey:firstLetter];
[IndexLetters addObject:firstLetter];
[indexArray release];
}
[indexArray addObject:record];// this is not workking
// NSLog(#" index array is %#",indexArray);
}
}
my INDEXRECORD is not showing correct value
i can now divide the section based on ABCD but each sections are having same content , what i am doing wrong

Answer 1

for example: say RecordsArray contains your all the records, now in table view datasource method numberOfSectionsInTableView call one more method to index your all the records like below
-(void)setUpRecordsForIndexing
{
if(IndexedRecords)
{
[IndexedRecords release];
IndexedRecords = nil;
}
if(IndexLetters)
{
[IndexLetters release];
IndexLetters = nil;
}
IndexedRecords = [[NSMutableDictionary alloc] init];
IndexLetters = [[NSMutableArray alloc] init];
NSString *miscKey = #"#";
for (NSString * recordName in RecordsArray)
{
NSString *firstLetter = ([recordName length] ==0)?miscKey:[[recordName substringToIndex:1]uppercaseString];
if(![firstLetter beginsWithCharacterInSet:[NSCharacterSet letterCharacterSet]] || [recordName isEqualToString:#""] || recordName == nil )
firstLetter = miscKey ;
NSMutableArray *indexArray = [mIndexedRecords objectForKey:firstLetter];
if (indexArray == nil)
{
indexArray = [[NSMutableArray alloc] init];
[IndexedRecords setObject:indexArray forKey:firstLetter];
[IndexLetters addObject:firstLetter];
[indexArray release];
}
[indexArray addObject:record];
}
}
and in numberOfSectionsInTableView return the count of IndexLetters. I hope this will solve your problem.

Answer 2

While indexing your records, keep your records in a dictionary say IndexedRecords. Such that, for key "A" set the array of records begin with letter "A". And while populating the table view
[[IndexedRecords objectForKey:[IndexLetters objectAtIndex:indexPath.section]]objectAtIndex:indexPath.row]
IndexLetters is also an array containing your index letters for the current list.