iOS - Refreshing content in UICollectionView custom cell

Question

I am pretty noob to iOS dev and Objective-C, I am making a brownie points app. I am using a sqlite DB that stores employee names and how many points they have, I also have a custom cell that displays the name and how many points they have on labels.

To increase the points they have I have a button on the cell, which points the SQL Update Statement needed for updating their points.

My issue is that when I click the button everything works but it doesnt display the updated points until I navigate away from the view and then back to it. I have tried :

[self.collectionview reloadData];

I have tried this in the button action and I have even tried adding a tap gesture recognizer so that whenever the user taps anywher it reloads the data. All with no success, I am not getting errors or crashes, it just doesnt refresh the labels.

Any Help will be hugely appreciated <3

Edit : If it helps, I have one class called DatabaseHelper that has all the methods to do with SQL in it .

This is my update method :

+(void)minusPoints:(NSString *)cell {
[self databaseInit];


if (sqlite3_open(dbpath, &peopleDB)== SQLITE_OK) {

    NSString *updateSQL = [NSString stringWithFormat:@"UPDATE PEOPLE SET POINTS = (POINTS - 1) WHERE ID =%@", cell];
    sqlite3_prepare_v2(peopleDB,[updateSQL UTF8String],-1,&statement,NULL);

    if (sqlite3_step(statement)== SQLITE_DONE) {
        NSLog(@"Updated Successfully");
    }
    else {
        NSLog(@"%s SQLITE_ERROR '%s' (%1d)", __FUNCTION__, sqlite3_errmsg(peopleDB), sqlite3_errcode(peopleDB));
    }
    sqlite3_finalize(statement);
    sqlite3_close(peopleDB);
}

}

Get data from DB :

+(NSMutableArray*)getData {
[self databaseInit];

peopleArray = [[NSMutableArray alloc] init];

if (sqlite3_open(dbpath, &peopleDB)== SQLITE_OK)
{

    NSString *selectSQL = @"SELECT ID, NAME, POINTS FROM PEOPLE ORDER BY POINTS DESC";
    sqlite3_prepare_v2(peopleDB,[selectSQL UTF8String],-1,&statement,NULL);

        while (sqlite3_step(statement)== SQLITE_ROW)
        {
            PersonObject *newPerson = [[PersonObject alloc]init];
            newPerson.ID = [[NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 0)]integerValue];
            newPerson.name = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 1)];
            newPerson.points = [[NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 2)] integerValue];
            [peopleArray addObject:newPerson];

        }
    NSLog(@"%s SQLITE_ERROR '%s' (%1d)", __FUNCTION__, sqlite3_errmsg(peopleDB), sqlite3_errcode(peopleDB));
    }

    sqlite3_finalize(statement);
    sqlite3_close(peopleDB);

return peopleArray;

}

Edit 2 : I have tried something like this in response to the first answer, still with no luck. (in ViewController.m )

//refresh cells
    -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    UITouch *touch = [[event allTouches]anyObject];
    if ([touch view]) {
    dispatch_async(dispatch_get_main_queue(), ^{
        [self.collectionView reloadData];
    });
}
   [super touchesBegan:touches withEvent:event];
}

Did you tried `[self.collectionview reloadData];` when you get the response from server? — Himanshu Joshi, Mar 11 '14 at 11:51
The question then is how do you load the data and how do you load the cells? Step through `-collectionView:cellForItemAtIndexPath:` after the call to `-reloadData` and see what data you are reloading. — Jeffery Thomas, Mar 11 '14 at 11:57
Where you are getting your response? Please provide the relevant code — Himanshu Joshi, Mar 11 '14 at 11:58
Please check this link [UICollectionView reload data ][1] [1]: http://stackoverflow.com/questions/18796891/uicollectionview-reloaddata-not-functioning-properly-in-ios-7 — ankyy, Mar 11 '14 at 11:59
here you are just updating the database. what is the patch where you are adding the values to an array of points and names — Himanshu Joshi, Mar 11 '14 at 12:03
Sorry guys, like i said i am a noob, i have edited to show the code that adds the values to the array — unselected, Mar 11 '14 at 12:06
@ankyy i have checked that before i posted my own question, didnt help me :/ — unselected, Mar 11 '14 at 12:07

score 0 · Answer 1 · answered Mar 11 '14 at 12:05

0

Try using the GCD:

dispatch_async(dispatch_get_main_queue(), ^{
    [self.collectionView reloadData]; 
});

answered Mar 11 '14 at 12:05

Joey Clover

746
5
12

Where would i use that ?? – unselected Mar 11 '14 at 12:20
wherever you originally called [self.collectionView reloadData]; – Joey Clover Mar 11 '14 at 12:21

iOS - Refreshing content in UICollectionView custom cell

1 Answers1