Display cell section wise crashes iOS app - ios

Question

I have Tableview with sections in it from A to Z (no of sections are not fixed i calculated dynamically)
I want to display like this:
:
My array values: msg_array=["AajKaCatch","AajKaItem","Anari","Big C Mobiles","Big Flix","BigRock","caksonflowers, ...."]
when i try to display like this in cellForRowAtIndexPath it shows NSInvalidArgumentException
cell.textLabel.text=[[[msg_array objectAtIndex:indexPath.section] objectAtIndex:indexPath.row] objectForKey:#"Merchant_Name"];
please help and Thanks In advance.

Answer 1

Your array is like:
array{object,object,object,object,object};
In such a situation, you can't use like:
[[msg_array objectAtIndex:indexPath.section] objectAtIndex:indexPath.row]
Because for implementing such one, the [msg_array objectAtIndex:indexPath.section] should return an array.
So implementing this, you need to try like this:
array{array{objects starts with 'A'},array{objects starts with 'B'},array{objects starts with 'C'}};

Answer 2

When you are doing this:
[[[msg_array objectAtIndex:indexPath.section] objectAtIndex:indexPath.row] objectForKey:#"Merchant_Name"];
You are accessing an element of msg_array as if it was a NSArray, that contains a NSDictionary.
But, inside of msg_array you just have NSStrings.
The structure you are triying to access is:
NSArray -> NSArray -> NSDictionary
And you have
NSArray -> NSString

Answer 3

I have done the same thing for contact info and other things like that using FKRSearchBarTableViewController, see the link and below is mine code for FKRSearchBarTableViewController
- (id)initWithSectionIndexes:(BOOL)showSectionIndexes withDataSource:(NSArray*) dataSource withControllerId:(int) ControllerId forGroup:(int)groupId
{
if ((self = [super initWithNibName:nil bundle:nil])) {
self.title = #"Search Bar";
NSLog(#"%d",groupId);
_groupID = groupId;
_controllerId = ControllerId;
_showSectionIndexes = showSectionIndexes;
_famousPersons = [[NSMutableArray alloc]initWithArray:dataSource];
if (showSectionIndexes) {
UILocalizedIndexedCollation *collation = [UILocalizedIndexedCollation currentCollation];
NSMutableArray *unsortedSections = [[NSMutableArray alloc] initWithCapacity:[[collation sectionTitles] count]];
for (NSUInteger i = 0; i < [[collation sectionTitles] count]; i++) {
[unsortedSections addObject:[NSMutableArray array]];
}
if(ControllerId == 5)
{
for (Person *personName in self.famousPersons) {
// NSInteger index = [collation sectionForObject:[personName objectForKey:#"FirstName"] collationStringSelector:#selector(description)];
NSLog(#"%#",personName.firstName);
NSInteger index = [collation sectionForObject:personName.firstName collationStringSelector:#selector(description)];
[[unsortedSections objectAtIndex:index] addObject:personName];
}
}
else
{
for (NSDictionary *personName in self.famousPersons) {
NSInteger index = [collation sectionForObject:[personName objectForKey:#"FirstName"] collationStringSelector:#selector(description)];
[[unsortedSections objectAtIndex:index] addObject:personName];
}
}
NSMutableArray *sortedSections = [[NSMutableArray alloc] initWithCapacity:unsortedSections.count];
for (NSMutableArray *section in unsortedSections) {
[sortedSections addObject:[NSMutableArray arrayWithArray:[collation sortedArrayFromArray:section collationStringSelector:#selector(description)]]];
}
self.sections = [NSMutableArray arrayWithArray:sortedSections];
}

Answer 4

to make the list more dynamic, solution should be
// given NSArray names = your full list of name
// NSArray indexes = your list of index
NSMutableArray *nameSections = [NSMutableArray arrayWithCapacity:26];
NSMutableArray *filteredIndexes = [NSMutableArray arrayWithCapacity:26];
for (NSString *index in indexes) {
NSPredicate *predicate = [NSPredicate predicateWithFormat:
#"SELF beginswith[c] %#",index];
NSArray *filterNames = [names filteredArrayUsingPredicate:predicate];
if(filterNames.count>0){
[nameSections addObject:filterNames];
[filteredIndexes addObject:index];
}
}
NSLog(#"filteredIndexes %#",filteredIndexes);
NSLog(#"nameSections %#",nameSections);
numOfSection = nameSections.count
numOfRow = [[numOfSection indexOfObject:section]count];
name = [[numOfSection indexOfObject:section]] indexOfObject:row];
// print log
//given indexes array a~z
names (
"a_string",
"a_string2",
"b_string",
"b_string2"
)
filteredIndexes (
a,
b
)
nameSections (
(
"a_string",
"a_string2"
),
(
"b_string",
"b_string2"
)
)