How can I get UITableViewCell object from a UIButton action method?

Question

I have a UITableView in which I have added a UIButton as accessory view for each cell. Note that I set the tag of the button as current row for future use.

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    // Configure the cell...

    if(cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];

        cellButton = [UIButton buttonWithType:UIButtonTypeCustom];
        cellButton.frame = CGRectMake(0, 0, 30, 30);  

        [cellButton setBackgroundImage:[UIImage imageNamed:@"cellButton.png"] forState:UIControlStateNormal];        
        [cellButton addTarget:self action:@selector(cellButtonAction:) forControlEvents:UIControlEventTouchUpInside];


        cellButton.tag = indexPath.row;  // <= Will use this in the next method
        cell.accessoryView = cellButton;
    }


    //Load cell with row based data

    return cell;
}

Now when one of these buttons is tapped, I need to make changes to the cell. So I implement cellButtonAction where I use the tag to get back the cell:

-(void)editCommentButtonAction:(id)sender
{
    UIButton *button = sender;
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:button.tag inSection:0];
    UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
    [self makeChangesToCell:cell];  
}

But this seems like a very round about way. Is there a cleaner way to do this?

Answer 1

So assuming that the button is in the contentView directly:

• ask "sender" (ie the button) for its superview, which is the cell's contentView

• ask that view for its superView, which is the cell

• ask the tabview for the index of this cell:

- (NSIndexPath *)indexPathForCell:(UITableViewCell *)cell

EDIT: Actually, I use a general purpose method or function now that just walks up the superviews, looking for a view that is 'KindOf' a UITableViewCell or a UICollectionViewCell. Works like a champ!

The code in Swift:

func containingUITableViewCell(tableView: UITableView, var view: UIView) -> (UITableViewCell, NSIndexPath)? {
while let v = view.superview {
    view = v
    if view.isKindOfClass(UITableViewCell.self) {
        if let cell = view as? UITableViewCell, let indexPath = tableView.indexPathForCell(cell) {
            return (cell, indexPath)
        } else {
            return nil
        }
    }
}
return nil

}

func containingUICollectionViewCell(collectionView: UICollectionView, var view: UIView) -> (UICollectionViewCell, NSIndexPath)? {
    while let v = view.superview {
        view = v
        if view.isKindOfClass(UICollectionViewCell.self) {
            if let cell = view as? UICollectionViewCell, let indexPath = collectionView.indexPathForCell(cell) {
                return (cell, indexPath)
            } else {
                return nil
            }
        }
    }
    return nil
}

Answer 2

You can do it in a easier way. You will get the table view cell using the sender parameter. Check the following code.

-(void)editCommentButtonAction:(id)sender
{
    UIButton *button = (UIButton *)sender;
    UITableViewCell *cell = (UITableViewCell*)[button superview];
    [self makeChangesToCell:cell];  
}

Here,

1. You are casting the sender of type id to a UIButton
2. You are calling the getter superview of that button, it will give you the UITableViewCell
3. Doing your customization.