UiButton文本不会在Tableview单元格中保持更改

Question

I have searched all over the web and cant seem to find a solution to this simple problem. I have a table view of buttons when the work "like". When the Button is pressed, it changes the word to "Unlike". I got it to work but when I scroll down the table, I see other buttosn also change to "unlike" and sometimes overlaps it with "Like". And when I scroll back up, the original button I selected changes back to normal state. I understand the cells are reusable and thats why I am using a mutable array for my data source and still it doesnt work. Please help!

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

if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
    }
    UIButton *myButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [myButton setTitle:@"Like" forState:UIControlStateNormal];
    myButton addTarget:self action:@selector(tapped:) forControlEvents:UIControlEventTouchUpInside];
    myButton.frame = CGRectMake(14.0, 10.0, 125.0, 25.0);
    myButton.tag =indexPath.row;
    [cell.contentView addSubview:myButton];
    cell.textLabel.text = [recipes objectAtIndex:indexPath.row];  
 return cell;
}

the action method:

-(void)tapped:(id)sender {
    UIButton *senderButton = (UIButton *)sender;

    UITableViewCell *parentCell = [[sender superview]superview];

    NSIndexPath *indexPathLiked = [table indexPathForCell:parentCell];

    [array replaceObjectAtIndex:senderButton.tag withObject:[NSNumber numberWithInt:1]];

    [sender setTitle:@"Unlike" forState:UIControlStateNormal];

}

Answer 1

If the table calls the cellForRowAtIndexPath you create all the time a new button. When you get a reused cell the button still exists and you put a new one over there.

Change your method to:

if (cell == nil) {
    cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
    UIButton *myButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [myButton setTitle:@"Like" forState:UIControlStateNormal];
    myButton addTarget:self action:@selector(tapped:) forControlEvents:UIControlEventTouchUpInside];
    myButton.frame = CGRectMake(14.0, 10.0, 125.0, 25.0);
    myButton.tag =indexPath.row;
    [cell.contentView addSubview:myButton];
}
else {
   // todo: change the button title to "like" or "unliked" value
}
cell.textLabel.text = [recipes objectAtIndex:indexPath.row];  

PS This make no sense, you doesn't use that, why you do that?

UITableViewCell *parentCell = [[sender superview]superview];
NSIndexPath *indexPathLiked = [table indexPathForCell:parentCell];

If you have only one section you can get the cell without using superview:

NSIndexPath *indexPath = [NSIndexPath indexPathForRow:sender.tag inSection:0]
UITableViewCell *parentCell = [table cellForRowAtIndexPath:indexPath];