Refresh tableview not working - ios

Question

I am new in objective-c developpment, I need to find a way to refresh my tableview.
I have 2 UIViewControllers, in the second one I insert data into my database and then I instantiate the first viewcontroller, it contains my tableview. I call a method that allows it to recover all of the data from the database, but when I use [tableview reloadData] nothing happens and cellforrowatindexpath isn't called.
econdviewcontroller:
//I insert data in database and I instanciate class where my tableview is and call refresh method
first = [[FirstviewController alloc]initWithNibName:#"FirstviewController" bundle:nil];
[first refreshList];
in Firstviewcontroller
-(void)refreshList{
self.tableview= [[[UITableView alloc] initWithFrame:self.view.bounds] autorelease];
tableview.dataSource = self;
tableview.delegate = self;
NSMutableArray *array = [[NSMutableArray alloc] init];
//I recover my data from data base
IPADAGRIONEActivityList *arrayActivities = [IPADAGRIONEActivity findAll];
if ([arrayActivities length] > 0)
{
for (IPADAGRIONEActivity * oneRec in arrayActivities)
{
[array addObject:oneRec];
}
}
//activities is NSMutablearray that contains all my data
self.activities = array;
//I build dictionnary
[self buildObjectsDictionnary:activities
NSLog(#"self.act%#",self.tableview);
[array release];
[self.tableview reloadData];
}
//numberofrowsinSection:
NSLog(#"rows%d",[[objects objectForKey:[objectsIndex objectAtIndex:section]] count]);
return [[objects objectForKey:[objectsIndex objectAtIndex:section]] ;
//numberOfSection:
NSLog(#"nbre of section%d",[objectsIndex count]);
return [objectsIndex count];}
//CellforRowatInddexPath: It dosen't access to this method
if (cell== nil) {
cell = [[MHCActivityListCell alloc]init];
}
IPADAGRIONEActivity *activite;
cell.activityCategory.text = [NSString stringWithFormat:#"%#", [activite EMAIL]];

Answer 1

You are instantiating a new tableview every time you call -refreshList. Remember that the tableView is a view, thus it needs to be added as a subview.
Once you understand that, you'll see that there is no reason to alloc+init a new instance of tableView every time you need it to refresh (and if, for any reason you need it, you need to add the tableView as a subview again). Basically, you need to make sure that the tableView that is being displayed is the same tableView that you're storing on your tableView property.

Answer 2

As mentioned earlier by Bruno, you are instantiating your tableview every time and this is not the right approach. You need to refresh the same tableview which had the original data.
in your refresh list do something like this
-(void) refreshList
{
// Get a reference to your viewcontroller's tableview
UITableview *tableview = [self tableview];
// Do your data manipulation
[tableview reloadData];
}