Change UITableView accessoryView on row select

I'm trying to change the accessory view of a UITableViewCell when its row is selected, I have the following code:

- (void)tableView:(UITableView *)aTableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
    UITableViewCell* cell = [self tableView:aTableView cellForRowAtIndex开发者_如何学运维Path:indexPath];
    UIActivityIndicatorView *activityView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite];
    [activityView startAnimating];
    cell.accessoryView = activityView;
    [activityView release];
}

But this isn't working. Any ideas?

You should not ask the tableview datasource (your self) for a cell. because this will create a new cell which is just not displayed.

replace

UITableViewCell* cell = [self tableView:aTableView cellForRowAtIndexPath:indexPath];

with

UITableViewCell *cell = [aTableView cellForRowAtIndexPath:indexPath];

    UIImage *normalImage = [UIImage imageNamed:@"cell-accessory.png"];
    UIImage *selectedImage = [UIImage imageNamed:@"cell-accessory-selected.png"];

    UIButton *accessoryView = [UIButton buttonWithType:UIButtonTypeCustom];
    accessoryView.frame = CGRectMake(0.0f, 0.0f, normalImage.size.width, normalImage.size.height);
    accessoryView.userInteractionEnabled = NO;
    [accessoryView setImage:normalImage forState:UIControlStateNormal];
    [accessoryView setImage:selectedImage forState:UIControlStateHighlighted];
    cell.accessoryView = accessoryView;