Rails 3 plugin nested_form versus JavaScript appraoch for adding form fields dynamically in a nested form

I am researching ways on how to dynamically add form fields for nested models and stumbled accross the nested_form plugin by ryanb. No doubt this is a a great piece of code, but I wondered why does it have to be so sophisticated?

Example: A form for creating / adding a project has one or more tasks assigned. The user can dynamically add more tasks by clicking on a add-task button. A project must have at least one task. Each task has a name and a de开发者_如何学Pythonscription.

So why not just: - When generating the html, sourround each set of task fields with a div given an ID such as "dynamic_fields" - When the user clicks the add-task button, call a JavaScript function via link_to_function to clone the dynamic_fields subtree. Insert the new set of fields at the bottom of the task list. - Via JavaScript, remove the values of the newly added fields and replace the child ID with something unique (Ryan suggests using a value based on the current time)

I am aware that the nested_forms plugin also works for deeper nesting structures, but given my simple use case with only one level of hierarchy, is the approach outlined above practical? Or am I missing something important? Any guidance on this topic is appreciated.

Basically, the plugin works as you describe but a form partial is used as the basis. The ids of nested objects must be unique and it's really easy to stick to the current millisecond time to do that.

Your way to handle the problem would work but would require some additional html to catch the required parts of the form and match what belongs to which additionnal object.

Ryan Bate's code seems complicated but it's not. It introduces complex methods only to make your view look good.

I think there is another solution to this question, a gem named cocoon.