CODEWITHSUNDEEP
objective-cipaduitableviewios6.1
Daniel Retief Fourie
Daniel Retief Fourie

Reputation: 626

iOS - deleting row from UITableView doesn't animate

I have a very frustrating issue. I have an app with a UITableView. When I am removing a cell from the table view, it is removed from the data model and then I call the following:

-(void)removeItem:(NSIndexPath *)indexPath {
    [self.tableView beginUpdates];

    [self.tableView deleteRowsAtIndexPaths:@[indexPath]
                      withRowAnimation:UITableViewRowAnimationRight];
    [self.tableView endUpdates];
}

My problem is, I've tried it like I do above, and I've tried without using animateWithDuration. I've even tried with a CATransaction, but however I do it, the animation doesn't happen.

I've got slow animations on in my Simulator and when I remove an item from the list, it removes correctly, but without animation. It just disappears and leaves a blank space for a moment before the table view data is reloaded.

I've search all over SO and Google and I can't seem to find an answer. Any ideas?

Does it perhaps have to do with the fact that I'm removing the object from the data model before calling the function above?

Edit: Removed the Animation Block as it is incorrect

Upvotes: 3

Views: 8535

Answers (4)

Kunal Gupta
Kunal Gupta

Reputation: 3074

[self.tableView beginUpdates];
[self.tableView insertRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationFade];
[self.tableView deleteRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationFade];
[self.tableView endUpdates];

indexPaths is an array of NSIndexPaths to be inserted or to be deleted in your table.

 NSarray *indexPaths = [[NSArray alloc] initWithObjects:
    [NSIndexPath indexPathForRow:0 inSection:0],
    [NSIndexPath indexPathForRow:1 inSection:0],
    [NSIndexPath indexPathForRow:2 inSection:0],
    nil];

Upvotes: 1

Fogmeister
Fogmeister

Reputation: 77641

First, you don't need to animate the change yourself.

Second, I think you need to make the changes to the datasource between the begin and end updates.

Your method should look something like this:

-(void)removeItemAtIndexPath:(NSIndexPath *)indexPath{

    [self.tableView beginUpdates];

    // I am assuming that you're just using a plain NSMutableArray to drive the data on the table.

    // Delete the object from the datasource.
    [self.dataArray removeObjectAtIndex:indexPath.row];

    // Tell the table what has changed.
    [self.tableView deleteRowsAtIndexPaths:@[indexPath]
                  withRowAnimation:UITableViewRowAnimationRight];

    [self.tableView endUpdates];
}

Upvotes: 2

Daniel Retief Fourie
Daniel Retief Fourie

Reputation: 626

Okay, I don't know if it's just bad manners, but I feel I'm going to answer my own question here.

First, thanks for all the other answers, you were all correct of course, but none of the answers solved my problem.

It turns out that there is another area in the code that does a different check then calls one of the tableView delegate methods, that seems to cancel the animation.

So the answer is as follows:

When you're row is removing but the animations aren't working, make sure that you are not calling didSelectRowAtIndexPath:indexPath before the animation starts. This will cancel the animations.

If you're NOT having that problem, here's some really typical code for expanding, two lines in the example:

Note that facebookRowsExpanded is a class variable you must have:

if ( [theCommand isEqualToString:@"fbexpander"] )
{
NSLog(@"expander button......");
[tableView deselectRowAtIndexPath:indexPath animated:NO];

NSArray *deleteIndexPaths;
NSArray *insertIndexPaths;

facebookRowsExpanded = !facebookRowsExpanded;
// you must do that BEFORE, not AFTER the animation:

if ( !facebookRowsExpanded ) // ie, it was just true, is now false
    {
    deleteIndexPaths = [NSArray arrayWithObjects:
            [NSIndexPath indexPathForRow:2 inSection:0],
            [NSIndexPath indexPathForRow:3 inSection:0],
             nil];
    [tableView beginUpdates];
    [tableView
        deleteRowsAtIndexPaths:deleteIndexPaths
        withRowAnimation: UITableViewRowAnimationMiddle];
    [tableView endUpdates];
    }
else
    {
    insertIndexPaths = [NSArray arrayWithObjects:
            [NSIndexPath indexPathForRow:2 inSection:0],
            [NSIndexPath indexPathForRow:3 inSection:0],
             nil];
    [tableView beginUpdates];
    [tableView
        insertRowsAtIndexPaths:insertIndexPaths
        withRowAnimation: UITableViewRowAnimationMiddle];
    [tableView endUpdates];
    }

// DO NOT do this at the end: [_superTableView reloadData];
return;
}

NOTE: your code for numberOfRowsInSection must use facebookRowsExpanded

(it will be something like "if facebookRowsExpanded return 7, else return 5")

NOTE: your code for cellForRowAtIndexPath must use facebookRowsExpanded.

(it has to return the correct row, depending on whether or not you are expanded.)

Upvotes: 3

IluTov
IluTov

Reputation: 6862

According to THIS you don't need to use the animateWithDuration:animations: at all.

Just try it like this

-(void)removeItem:(NSIndexPath *)indexPath {
    [self.tableView beginUpdates];
    [self.tableView deleteRowsAtIndexPaths:@[indexPath]
                  withRowAnimation:UITableViewRowAnimationRight];
    [self.tableView endUpdates];
}

Upvotes: 7

Related Questions