Subclassing UITableViewCell with its own Nib

Question

I'd like to create a custom UITableViewCell subclass that loads content asynchronously using a URL connection. I've got a UITableViewCell subclass that handles all of this and a Nib file that defines the layout of the cell, but I'm having trouble linking the two. Here's the code I'm using in tableView:cellForRowAtIndexPath :

static NSString *FavCellIdentifier = @"FavCellIdentifier";

FavouriteCell *cell = [tableView dequeueReusableCellWithIdentifier:FavCellIdentifier];

if (cell == nil)
{
    cell = [[[FavouriteCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:FavCellIdentifier] autorelease];
}

cell.requestURL = [NSURL URLWithString:[NSString stringWithFormat:@"%@?%@=%i", URL_GET_POST_STATUS,
                                           URL_PARAM_SERIAL,
                                           [[self.favourites objectAtIndex:indexPath.row] intValue]]];

return cell;

This gives a request URL to the UITableViewCell subclass, which handles loading in the setRequestURL method.

In the FavouriteCell class I've kept the initWithStyle:reuseIdentifier: method as is, and in the Nib I've set FavCellIdentifier as the identifier, and FavouriteCell as the class. Now how do I make the FavouriteCell class load the Nib?

Answer 1

In order to use the nib/xib file, you're going to have to instantiate the FavouriteCell differently.

Try this:

1. Make sure you've changed the type of your UITableViewCell to be a subclass of FavouriteCell instead of the default UITableViewCell in your xib. Do this by:
   • Clicking on the cell in the objects pane of Interface Builder.
   • Then, go to the Identity Inspector tab and make sure the Class selection under Custom Class lists FavouriteCell .
2. Change the File's Owner property to be the UIViewController where you want to display your custom UITableViewCell (pretty much same process as step #1).
3. Add an IBOutlet property of type FavouriteCell to your UIViewController . Name it whatever you like (I'm going to call it cell ).
4. Back in the xib of the UITableViewCell , connect the IBOutlet for the cell property in File's Owner to your custom UITableViewCell .
5. Use this code to load the cell programmatically:
   

---

- (FavouriteCell *)tableView:(UITableView *)tableView 
       cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    static NSString *CellId = @"FavCellId";
    FavouriteCell *cell = [tableView dequeueReusableCellWithIdentifier:CellId];
    if (!cell) {
        // Loads the xib into [self cell]
        [[NSBundle mainBundle] loadNibNamed:@"FavouriteCellNibName" 
                                      owner:self 
                                    options:nil];
        // Assigns [self cell] to the local variable
        cell = [self cell];
        // Clears [self cell] for future use/reuse
        [self setCell:nil];
    }
    // At this point, you're sure to have a FavouriteCell object
    // Do your setup, such as...
    [cell setRequestURL:[NSURL URLWithString:
                  [NSString stringWithFormat:@"%@?%@=%i", 
                      URL_GET_POST_STATUS, 
                      URL_PARAM_SERIAL, 
                      [[self.favourites objectAtIndex:indexPath.row] intValue]]
     ];
    return cell;
}