Remove the "None" option from the fallback select list

So you're suggesting that "none" be the first option? I don't actually like "none" much at all and I wouldn't recommending using it, since it actually makes the field impossible to enter anything at all. Up until the last round of changes, it also made it so that you couldn't even later edit the node and add a reference. Right now it's difficult to hide certain fields based on if a field is required or not, since the "Required" checkbox is on the same page, we'd have to do an AJAX request to properly hide/show the radiobutton, which I'm not very keen on, especially since I don't think it really makes much sense to do so.

I'm terribly confused (I thought you were talking about the "leave empty" widget, not the "none" option in select lists), could you post a screenshot? Node Reference URL Widget uses the normal Node Reference widgets for everything, so it should behave exactly the same when using the fallback behaviors.

the thing that irritates me is that when the field is required, you have none on the list.

As far as I know the "None" option will only show up in the select list if you haven't set a default value. If you set a default value for the list, this "None" option will disappear. Again, this is a Node Reference issue more than a Node Reference URL issue, since that functionality is provided by Node Reference itself.

From a user interaction perspective, a required field should not have none as an option.

This isn't necessarily true, while "none" is a poor title ("select..." is more appropriate), it can be useful if you don't want to introduce selection bias just because the first option is already selected for you, resulting in users not changing the default. A good example of this is something like a drop-down of states. Even though it may be required, you probably don't want "Arkansas" to be the default.

Or can we be allowed to select a default value?

I think maybe Node Reference URL Widget might turn off the default value select (not sure about this), because it's assumed that a default is going to already be provided through the URL.

I've been battling this too. Turns out the - None - value is always added by Node Reference URL in an after_build handler. Quicksketch, I see your point on the selection bias. I may just hide mine with JQuery because I ensure that there is always one valid choice, but an option on the field settings would be nice.

I don't find this a problem enough that I'll spend any time on it. If you'd like to recommend a patch I'll review it.

Here is the patch.

IMHO, it seems that there either needs to be the ability to set a default value as part of the "Fallback behavior" process and/or to at least remove "none" when the field is required (like in manur0's patch in #10, which seems to work for me)

Any thoughts?

manur0's patch in #10 doesn't address my concern from #6. Required and an empty option are not mutually exclusive. I think restoring the ability to set a default value as part of the fallback is a better way to go. Again, I'm not spending time on this though, so I'm moving it back to postponed. Please set to needs review if a patch can be provided.