W3C home > Mailing lists > Public > www-forms@w3.org > November 2006

Re: repeats

From: Jason <jeacott@hardlight.com.au>
Date: Fri, 03 Nov 2006 17:52:43 +1030
Message-ID: <454AEE43.40801@hardlight.com.au>
To: Lee Standen <nom@standen.id.au>, www-forms <www-forms@w3.org>

Hi Lee,
	I think you've missed my point.
Insert now only seems to work if you actually have some data.
if you start with data - remove it all with <delete... at.../>
then <xforms:insert bind="bind_1" at="index('repeat_1')" 
position="after"/> no longer does anything at all.

I've tried chiba, the firefox extension, and formsplayer and they all 
behave this way.



Lee Standen wrote:
> 
> Yep, insert works by duplicating the previous set of nodes, which you 
> can then use <xf:setvalue> to clear as necessary.
> 
> There was a trick somewhere to actually have a 'template' to pull the 
> new set of records from...I'll try and find it.
> 
> Jason wrote:
>>
>> Hi all, Today I decided it was time to upgrade the version of chiba 
>> I've been using for my xforms only to find that its behaviour has 
>> changed. I checked a few other implementations and they all seem to 
>> agree on this point, so I'm totally confused.
>>
>> up until now I've been using a trigger with something like:
>>  <xforms:insert bind="bind_1" at="index('repeat_1')" position="after"/>
>>
>> in order to allow form users to add items to lists. BUT if they remove 
>> all the items from the list then this no longer works and I apparently 
>> need a completely different button to get the first item on the list 
>> again. Is this true? My existing copy of chiba just inserts, even if 
>> there are currently no items in the list. how is this supposed to 
>> work? how have people built real life forms to cope with this odd 
>> behaviour(imho)
>> I've had another look at the w3c position for xforms 1.0 and it seems 
>> to suggest that this behaviour is designed (unless the "homogeneous 
>> collection" is actually meant to mean the collection that exists at 
>> form startup including any implied nodes from binding lazily? )
>>
>> ref: http://www.w3.org/TR/xforms/slice9.html#action-insert
>> The homogeneous collection to be updated is determined by evaluating 
>> the Node Set Binding. If the collection is empty, the insert action 
>> has no effect.
>> The rules for selecting the index are as follows:
>> b) If the result is NaN, the insert appends to the end of the node-set.
>>
>> c) If the resulting index is outside the valid range of the node-set, 
>> it is replaced with either 1 or the size of the node-set, whichever is 
>> closer.
>>
>> so how should a shopping cart for example actually be built?
>> I want:
>> add item
>> remove item
>> checkout
>>
>> I dont want an append item for the case that there are none items, and 
>> I really dont want to have to specially bother with the zero case (how 
>> is this done anyway?).
>>
>> what am I missing?
>>
>> much lost
>> Jason.
>>
> 
> 
Received on Friday, 3 November 2006 07:42:27 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Saturday, 10 March 2012 06:22:07 GMT