self.objects is empty in PFQueryTableViewController - ios

Question

I am trying to display data in different sections using PFQueryTableViewController. The code suggested in https://parse.com/questions/using-pfquerytableviewcontroller-for-uitableview-sections seemed to work, but I couldn't get the data to load on self.objects. Here is my code:
#import "AKAdminViewStudentsViewController.h"
#interface AKAdminViewStudentsViewController ()
#property (strong, nonatomic) NSMutableDictionary *sections;
#property (strong, nonatomic) NSMutableDictionary *sectionToClassMap;
#end
#implementation AKAdminViewStudentsViewController
#synthesize sections = _sections;
#synthesize sectionToClassMap = _sectionToClassMap;
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
if (self) {
self.parseClassName = #"Students";
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
[self.tableView reloadData];
NSLog(#"sections found: %#", self.sections); // returns null
NSLog(#"sectionToClassMap: %#", self.sectionToClassMap); // returns null
NSLog(#"objects in table: %#", self.objects); // this found to be empty
}
...
#pragma mark - Tableview methods
- (PFQuery *)queryForTable
{
PFQuery *queryStudents = [PFQuery queryWithClassName:#"Students"];
[queryStudents whereKey:#"student_admin" equalTo:[PFUser currentUser]];
if ([self.objects count]==0) {
queryStudents.cachePolicy = kPFCachePolicyCacheThenNetwork;
}
[queryStudents orderByAscending:#"class_name"];
return queryStudents;
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return self.sections.allKeys.count;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
NSString *className = [self classForSection:section];
NSArray *rowIndicesInSection = [self.sections objectForKey:className];
return rowIndicesInSection.count;
}
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
NSString *className = [self classForSection:section];
return className;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath object:(PFObject *)object
{
static NSString *CellIdentifier = #"Students";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (cell==nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
}
// Configure cell
cell.textLabel.text = [NSString stringWithFormat:#"%#", object[#"full_name"]];
NSDateFormatter *formatDate = [[NSDateFormatter alloc] init];
[formatDate setDateStyle:NSDateFormatterShortStyle];
cell.detailTextLabel.text = [NSString stringWithFormat:#"%#", [formatDate stringFromDate:object[#"createdAt"]]];
return cell;
}
#pragma mark - Helper methods
- (void)objectsDidLoad:(NSError *)error
{
[super objectsDidLoad:error];
// Clear data before loading
[self.sections removeAllObjects];
[self.sectionToClassMap removeAllObjects];
NSInteger section = 0;
NSInteger rowIndex = 0;
for (PFObject *object in self.objects) {
NSString *className = [object objectForKey:#"class_name"];
NSMutableArray *objectsInSection = [self.sections objectForKey:className];
if (!objectsInSection) {
objectsInSection = [NSMutableArray array];
// Create new section for new class found
[self.sectionToClassMap setObject:className forKey:[NSNumber numberWithInt:section++]];
}
[objectsInSection addObject:[NSNumber numberWithInt:rowIndex++]];
[self.sections setObject:objectsInSection forKey:className];
}
}
- (PFObject *)objectAtIndexPath:(NSIndexPath *)indexPath
{
NSString *className = [self classForSection:indexPath.section];
NSArray *rowIndicesInSection = [self.sections objectForKey:className];
NSNumber *rowIndex = [rowIndicesInSection objectAtIndex:indexPath.row];
return [self.objects objectAtIndex:[rowIndex intValue]];
}
- (NSString *)classForSection:(NSInteger)section
{
return [self.sectionToClassMap objectForKey:[NSNumber numberWithInt:section]];
}
#end
When I look at the NSLog data, self.objects is empty. I know this is the reason why data isn't displayed, and would like some advice to sort this out please! Thanks.