Show a UIPopoverController from a detail disclosure button in a UITableViewCell

I am creating an application for the iPad, and I want to show an UIPopoverController with an arrow pointing to the detail disclosure button for the row it belongs to. I want to do this in the tableView:accessoryButtonTappedForRowWithIndexPath: method. Currently I have this, with a dummy CGRect:

- (void)tableView:(UITableView *)tableView accessoryButtonTappedForRowWithIndexPath:(NSIndexPath *)indexPath {
    // Dismiss in the case it shows itself somewhere else
    [addFeedPopup dismissPopoverAnimated:YES];

    // Set up
    TNSubscribeToFeedController *subscribeToFeedController = [[TNSubscribeToFeedController alloc] initWithNibName:@"SubscribeToFeed" bundle:nil];
    UINavigationController *subscribeToFeedNavigationController = [[UINavigationController alloc] initWithRootViewController:subscribeToFeedController];
    subscribeToFeedController.title = @"Subscribe to feed";
    subscribeToFeedController.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:nil];
    subscribeToFeedController.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:nil];
    /*
     * Note that we use the UINavigationController pure for the nices UINavigationBar.
     */

    // Show in popup
    addFeedPopup = [[UIPopoverController alloc] initWithContentViewController:subscribeToFeedNavigationController];
    addFeedPopup.popoverContentSize = CGSizeMake(480, 320);
    [addFeedPopup presentPopoverFromRect:CGRectMake(0, 0, 20, 20) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionLeft animated:YES];

    // Memory
    [subscribeToFeedNavigationController release];
    [subscribeToFeedController release];
}

Also, when the UITableView is in editing mode, the detail disclosure button is about 60 pixels to the left, since I use this to set up my rows:

if (cell == nil) {
    cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:@"SectionTwoCell"] autorelease];
}
cell.textLabel.text = [NSString stringWithFormat:@"Feed %d", indexPath.row];
cell.detailTextLabel.text = @"Description";
cell.accessoryType = UITableViewCellAccessoryDetailDisclosureButton;
cell.edit开发者_如何学编程ingAccessoryType = cell.accessoryType;
//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^//
//        TWO LINES BACK DEAR SO USER        //

Can anyone help me with this problem? Thanks.

Oh, and is it also possible to disable scrolling and disable selecting anything until the UIPopoverController is closed (perfectionism)?

To do what you want, you need an accessoryView and setting the accessoryType does not create one. However, it will work if you create a button and set it as the cell.accessoryView.

Create and set the accessoryView when the cell is created:

    ...
    UIButton *disclosureButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
    [disclosureButton addTarget:self action:@selector(discloseDetails:) forControlEvents:UIControlEventTouchUpInside];
    cell.accessoryView = disclosureButton;
    ...

Replace tableView:accessoryButtonTappedForRowWithIndexPath: with discloseDetails:. This looks much like what you have before so I've only put the changes below:

- (void) discloseDetails:(UIButton *)sender {
    ...
    UITableViewCell *cell = (UITableViewCell *) sender.superview;
    NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];  // if needed
    [addFeedPopup presentPopoverFromRect:cell.accessoryView.bounds inView:cell.accessoryView permittedArrowDirections:UIPopoverArrowDirectionLeft animated:YES];
    ...
}

If you don't need the cell, it can be made even simpler:

- (void) discloseDetails:(UIButton *)sender {
    ...
    [addFeedPopup presentPopoverFromRect:sender.bounds inView:sender permittedArrowDirections:UIPopoverArrowDirectionLeft animated:YES];
    ...
}

Here's what it looks like