reloadData not working with UITableView

Question

reloadData not working with UITableView

I have some arrays which I update throughout my program and my UITableView needs to reflect these changes. I have the dataSource and delegate set properly because I can edit the UITableView. My problem is that when I call the reloadData function, nothing changes. I know my arrays have data in them because if I NSLog the count then I get more than 0.
I've put breakpoints in the UITableView controller and it looks like the reloadData is just getting ignored. The breakpoints only fire once when the view loads up, not when reloadData is called.
I'm declaring the UITableView in the header file like this

@interface FriendsTableController : UITableViewController {
IBOutlet UITableView * tblView;
}

Then in the .m file I've got this:
@synthesize tblView;

I'm trying to call the reloadData like this:
[tblView reloadData];

Have I over looked something?
Thanks,
Tom

Macbook 13.3", Mac OS X (10.5.6)

Posted on Dec 24, 2008 12:47 PM

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Answer 1

bones237

Level 1

10 points

Dec 24, 2008 6:46 PM in response to harrytheshark

You're passing a message ("reloadData") to an object ("tblView") so therefore it needs to be in brackets.


[tblView reloadData];

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Answer 2

Dec 25, 2008 3:19 PM in response to harrytheshark

Sorry I am calling it with the brackets, still not working.
Tom

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Answer 3

Satake

Level 1

55 points

Dec 25, 2008 5:38 PM in response to harrytheshark

I'd guess you didn't connect the 'tblView' in interface builder.

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Answer 4

andlabs

Level 2

174 points

Dec 25, 2008 8:18 PM in response to bones237

bones237 wrote:
You're passing a message ("reloadData") to an object ("tblView") so therefore it needs to be in brackets.
[tblView reloadData];

The original poster did not know about the code markup tag that you used in your post, therefore he wound up linking to the contents of the code itself. That is, use code blocks: { code } and { /code }, without spaces. Proof: hover your mouse over the original post: it's a link! [And so is this, since I put it in brackets].

End of (possibly pointless) chastisement.

Message was edited by: andlabs

Message was edited by: andlabs

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Answer 5

Dec 26, 2008 3:19 AM in response to Satake

I have definately connected it in the interface builder because I can add rows to begin with, I just can't reload it.
The confusing thing is that when I add breakpoints the debugger doesn't even get to them on the reloadData call, just when the view first loads.

Tom

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Answer 6

navac

Level 1

0 points

Dec 26, 2008 3:32 AM in response to harrytheshark

Where do you call it? Try to call it in viewWillAppear function.

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Answer 7

Dec 26, 2008 6:01 AM in response to navac

I'm trying to call it in a void function because this function updates an array I'm trying to populate the UITableView with.

Tom

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Answer 8

Dec 26, 2008 4:02 PM in response to harrytheshark

-(void)refreshTable:(NSArray)myArray:(NSArray*)mySecondArray:(NSArray*)myThirdArray:(NSArray)myForthArray {
 //The "another" arrays are declared in the header file
 anotherArray=myArray;
 anotherSecondArray=mySecondArray;
 anotherThirdArray = myThirdArray;
 anotherForthArray = myForthArray;
 NSLog(@"Refresh Table Function");
 NSLog([NSString stringWithFormat:@"anotherArray count = %i",[anotherArray count]]);
 [tblView reloadData];
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
 return [anotherArray count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
 
 static NSString *CellIdentifier = @"Cell";
 
 UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
 if (cell == nil) {
 cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
 }
 
 // Set up the cell...
 
 cell.text = [[NSString alloc] initWithFormat:@"Row %i)",indexPath.row];
 return cell;
}

I know the function is getting called because the log displays the two messages and I know the anotherArray has objects because it says so in the log. It's just the reloadData that isn't working because the UITableView has no rows even after the reload call.
I know the table works because if I change the numberOfRowsInSection to return 10 then I get 10 rows of "Row 0", "Row 1" etc.

Thanks,
Tom

Message was edited by: harrytheshark

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Answer 9

navac

Level 1

0 points

Dec 27, 2008 11:11 AM in response to harrytheshark

but where do you put the call to refreshTable? I call reload from viewWillAppear function, which is called before & after you get into editing state or the view is popped from the stack and will be shown again. When exactly you'd expect this function to work?
May be you call it too late, after the table has been already formed...

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Answer 10

Dec 27, 2008 12:18 PM in response to navac

I put it in another classfile after the data for the table has been collected. Basically my apps signs into a website then grabs some data, I need this data to be displayed in the table. The app then updates the data every minute or so, so I need to be able to constantly reload the table.

The table has been formed before log in and data grabbing is complete, but I thought that a table could be reloaded at any time?

Tom.

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Answer 11

navac

Level 1

0 points

Dec 27, 2008 10:20 PM in response to harrytheshark

As far as I know calling it constantly will not do the job. You should call it before you show your view, otherwise what you see on the screen will not be updated. I don't know how did you build your GUI in this regard, but I'd suggest you to rebuild the data array only and call reloadData only when you're going to push your view on the stack.

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Answer 12

Dec 28, 2008 3:47 AM in response to navac

So there is no way of changing how the TableView looks after it's loaded? The native mail program has to pull in new mail and add it to what looks like a TableView?
Is there another view which could do the job? I need something that can display a list and be updated on demand.

Thanks for all the help,
Tom

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Answer 13

navac

Level 1

0 points

Dec 28, 2008 11:09 AM in response to harrytheshark

Googling reloadData brings some interesting link, where they call for a timer to let the table refresh itself. May be you'll found this useful:

http://code.google.com/p/inewsgroup/source/browse/trunk/GroupView.m?r=94

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Answer 14

Dec 28, 2008 11:36 AM in response to navac

Thanks a lot!
I managed to devise that calling

[[self tableView] reloadData];

works. Well kind of. My breakpoint is now stopping at numberOfRowsInSection when it didn't before. However it still doesn't seem to be adding any rows to the table.

Tom

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Answer 15

navac

Level 1

0 points

Dec 28, 2008 12:13 PM in response to harrytheshark

You have do it by yourself using interfaces like insertRowsAtIndexPaths/deleteRowsAtIndexPaths, same with section before you reload your table data. These functions thou can be tricky, so use them carefully

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