[Form] extend the documentation on dynamic form modification

[luebbert42]

I suggest to add the following information either to the documentation or the cookbook

• details on the different event times (when to use what)
• example: how to pass data to the event listener using Doctrine entities/not using entities
• information: how to set the order of the added form elements (possible at all or responsibility of the template?)

I am referring to http://symfony.com/doc/current/cookbook/form/dynamic_form_modification.html

[weaverryan]

Hi Dorthe!

+1 for details on different event times (when to use what)
+1 for making sure we're showing at least one outside "thing" being made accessible to the event listener, whether this is some outside data or a service
-1 for the re-ordering - I believe this is the responsibility right now (for better or worse) of the template

We should review the document and make these changes, but only after #1842 has been merged in.

Thanks!

[luebbert42]

Ryan, that's perfectly fine that ordering is done in the template, but it should be noted somewhere. My English is sometimes ... interesting... but if I can support you somehow in preparing something, let me know :-)

[weaverryan]

This issue is ready to be worked on - there are additional changes needed in #2464.

[cheesemacfly]

I do believe the YAML configuration sample at the end of this page has some typos.

[xabbuh]

@cheesemacfly what do you mean?

[cheesemacfly]

@xabbuh Shouldn't the @doctrine argument for acme.form.meetup_registration_listener be @doctrine.orm.entity_manager instead?

[wouterj]

@cheesemacfly you're completely correct. There is already a fix for that in #2743

[cheesemacfly]

@wouterj you are right. Thanks for the information!

[weaverryan]

I've just merged in that fix! I'm going to close this issue - my intention was to use #2464 going forward to follow the issues with this entry.

Thanks!

[barnibx]

Hi guys,

would you be kind, and share the link where I can find these additional documentation?
I'm getting issues build up that example based on just those information from the cookbook (http://symfony.com/doc/current/cookbook/form/dynamic_form_modification.html).

Thank you in advance.

[xabbuh]

Hi @barnibx, which additional documentation are you talking about?

[barnibx]

Hi @xabbuh,
I was referring to @weaverryan 's comment, on:
+1 for details on different event times (when to use what)
+1 for making sure we're showing at least one outside "thing" being made accessible to the event listener, whether this is some outside data or a service
-1 for the re-ordering - I believe this is the responsibility right now (for better or worse) of the template.

I realized after my comments, that I can check the modifications on each issue (#xxc), but I was wondering if these additions can be found in one place with some examples.

Thanks for your question.

[weaverryan]

Hey @barnibx - these have all been put into different parts in this article: http://symfony.com/doc/current/cookbook/form/dynamic_form_modification.html. We more or less addressed these issues, but we don't talk directly about, for example, when to use the different form events (that article uses FormEvents::PRE_SET_DATA several times). If there's something missing that you'd like to see, please definitely open an issue :).

Cheers!

[barnibx]

HI @weaverryan,

Thanks for your response.
Maybe I missed something, but I think it would be really useful if you could add an example/explanation how can be built a dynamic form with changing more fields depending on another field.
For example if I have a list of checkboxes for a country regions, and each region has his own fields which needs to be completed. So what would be a nice solution(based on form events) to show different twig templates on each region selection.
I understand that this will affect different sections (entities, controllers, twig templates, AJAX calls) but I think this tutorial it would make some developer's life much easier :)

Thanks in advance.