Question

I am implementing a table index view and amazed to see how my table indexes are working even without implementing:

 - (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index method.

I have only implemented:

 - (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView 

Strangely, when I am running in breakpoints, Once i click on any of the index values my

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

method is getting called.

Any clue why this is so happening and what is the significance of sectionForSectionIndexTitle method then.

Answer 1

if you have a list of all letters in alphabet and your list only contains some entries, you could use the following code:

//Asks the data source to return the index of the section having the given title and section title index.
– (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index {

if (tableView == self.searchDisplayController.searchResultsTableView || self.searchBar.text.length > 0)
{
    return 0;
}
else
{

    //direct - firsttime match
    if([self.realMIndexArray containsObject:title]) {
        NSInteger count = 0;
        for(NSString *character in self.realMIndexArray)
        {
            if([character isEqualToString:title]){
                return count;
            }
            count ++;
        }
    }
    else {

        //take next higher letter from alphabet and check if its contained in the "available letters list"
        //if not, select last entry of list
        for(int i = [self.indexArray indexOfObject:title] + 1; i < [self.indexArray count]; i++) {

            NSString* character = [self.indexArray objectAtIndex:i];

            if([self.realMIndexArray containsObject:character]) {

                return [self.realMIndexArray indexOfObject:character];

            }

        }

        return [self.realMIndexArray count] - 1;

    }
    return 0;// in case of some eror donot crash d application

}

}

realMIndexArray count == letters really existing in list
indexArray = list of all letters in alphbeth.

hope this helps someone (took me a little bit of time to figure it out)