Dynamically-Sized List of Fields in Yesod - forms

In HTML, multiple fields can be specified with a non-unique name like so:
<input type="checkbox" name="breakfast" value="eggs">
<input type="checkbox" name="breakfast" value="bacon">
so that, when submitted, query parameters get passed like (if both boxes are ticked) breakfast=eggs&breakfast=bacon. The CGI specification states that this should be interpreted as an array or list of values, and this technique is also useful for dynamically-sized lists of inputs:
<input type="text" name="url">
<input type="button" value="Moreā€¦"
onclick="var s = document.createElement('input');
s.type='text';
s.name='url';
this.form.appendChild(s);
return false;">
However, I can see no way to get list-valued inputs from a form in Yesod. Is there any way to do such a thing?

Most of the prebuilt fields work on inputs with a single input (with a notable exception for multiSelectField). To achieve what you're looking for, you probably want to create a custom Field. Notice that the fieldParse function takes a list of Text values, specifically to allow your use case.
The chapter on forms includes a section on custom fields.

Related

angularjs form can not refer to input control when input name is array

I encounter a problem when testing form validation with angularjs
According to angularjs form guide,
an input control that has the ngModel directive holds an instance of NgModelController. Such a control instance can be published as a property of the form instance using the name attribute on the input control.
I created test code at plunker, it all works fine untill I change the input name from
<input type="number" name="age" ng-model="user.age" max="100" required>
<p>{{form1.age.$error}}</p>
to
<input type="number" name="user[age]" ng-model="user.age" max="100" required>
<p>{{form1.user[age].$error}}</p>
Does this mean angular can not recognize array syntax in form input?
The problem for me is I want to keep the normal form submission flow and only use angular for form validation, so I need to keep form input as array to work with the backend form handling
It has nothing to do with Angular. It is a syntactic JS error.
If you want to reference a property named user[age], you should do it like this:
form1['user[age]'].$error
form1.user[age] is incorrectly interpreted as (form1.user)[age]

Create repeatable custom form fields in web2py?

I want to create twitter bootstrap compliant form. According to the docs for Twitter Bootstrap v2.2.2 (the version included with web2py) the html should look like:
<form class="form-horizontal">
<div class="control-group">
<label class="control-label" for="inputEmail">Email</label>
<div class="controls">
<input type="text" id="inputEmail" placeholder="Email">
</div>
</div>
...
I'm currently using SQLFORM which outputs html that doesn't really fit with this (even using formstyle='divs'). Besides I want my html output to be clean without web2py artifacts such as class="w2p_fl". So my thought is to use a custom form. However in doing this there would be a lot of repeated code. That is, the following would basically need to be repeated for each field.
{{=form.custom.begin}}
<div class="control-group">
{{=LABEL(form.custom.label['myfield'], _class='control-label',
_for='mytable_myfield')}}
<div class="controls">{{=form.custom.widget.myfield}}</div>
</div>
...
{{=form.custom.end}}
So how can I repeat the above unit of code so I could replace it with something like {{=bootstrap_field(db.mytable.myfield)}} or some other way to adhere to DRY?
What is the web2py way to do this? Create a view function? Pass a function in the dictionary returned by the controller? Create my own html helper? Create my own widget? Another way?
If you're using Bootstrap 2, you can just do:
form = SQLFORM(..., formstyle='bootstrap')
For Bootstrap 3 (or any other custom formstyle you'd like to create), the formstyle argument can be a function (or other callable) that produces the form DOM. The function will be passed the form and a fields object, which is a list of tuples, with each tuple containing a CSS id, label, input element, and (possibly empty) comment/help text. To get an idea of what such a function should look like, check out the one used for Bootstrap 2 forms.

MODx eForm: populating hidden fields

My goal is, that eForm populates hidden fields with data my script receives from a database. I was able to successfully populate all visible input fields with my function called through &eFormOnBeforeFormParse. When I want to populate hidden fields, it does not work. They are empty or MODx/eForm complains that the form was tampered with.
I could just throw the data in regular input fields and hide them with css, but is there a way to do this appropriately with type="hidden" fields?
Use the eform attribute to prevent validation of hidden fields:
<input type="hidden" name="calculatedField" value="" eform="::0::" />
More info here:
http://wiki.modxcms.com/index.php/EForm#Hidden_fields.2C_select_boxes.2C_radio_options_and_checkbox_fields

Play 2.0 Nested forms: generate <input id="email"> instead of <input id="user_email">

Posted this to Play user group; I account for the sole view, so hoping to get a view, or perhaps even an answer ;-)
Nested forms are great, but there's one glitch that adds boilerplate to either javascript or scala templates.
For example, given:
#inputText(field = _form("user.email"),
'_label-> "Email Address*",
'class-> "required email",
'placeholder-> "jdoe#gmail.com"
)
the generated input field is something like:
<input id="user_email" name="user.email" ...>
Now, when you want to validate the email address client-side you then have to reference DOM id: $('#user_email')
Where $('#email') would be more natural.
I know I can set the id attrib manually in the template but would prefer to, by default, have the nested name (user in this case) stripped out from the id attrib.
Looking in github views helper directory, I am not finding where I can get access to the generated id (i.e. which file I need to overload and how).
Anyone know how to pull this off and/or have a better approach?
Here is where the field's ID is auto-generated:
https://github.com/playframework/Play20/blob/master/framework/src/play/src/main/scala/play/api/data/Form.scala#L274
There's not really any way you can override that behaviour, but you could write your own #inputText helper that strips the "user_" part from the ID when generating the HTML.
Basically copy-paste the default helper and replace
<input type="text" id="#id" ...
with your own code, e.g.
<input type="text" id="#processFieldId(id)" ...
or (untested!):
<input type="text" id="#(id.split('_').last)" ...
Then just import your custom helper in your template, and use it just like you would use #inputText.

jQuery ajaxSubmit(): ho to send the form referencing on the fields id, instead of the fields name?

im pretty new to jQuery, and i dont know how to do that, and if it can be done without editing manually the plugin.
Assume to have a simply form like that:
<form action="page.php" method="post">
Name: <input type="text" name="Your name" id="contact-name" value="" />
Email: <input type="text" name="Your email" id="contact-email" value="" />
</form>
When you submit it, both in 'standard' way or with ajaxSubmit(), the values of the request take the label of the field name, so in the page.php i'll have:
$_POST['Your name'];
$_POST['Your email'];
Instead i'll like to label the submitted values with the id of the field:
$_POST['contact-name'];
$_POST['contact-email'];
Is there a way to do that with jquery and the ajaxsubmit() plugin?
And, maybe, there is a way to do it even with the normal usage of a form?
p.s: yes, i know, i could set the name and id attributes of the field both as 'contact-name', but how does two attributes that contain the same value be usefull?
According to the HTML spec, the browser should submit the name attribute, which does not need to be unique across elements.
Some server-side languages, such as Rails and PHP, take multiple elements with certain identical names and serialize them into data structures. For instance:
<input type="text" name="address[]" />
<input type="text" name="address[]" />
If the user types in 1 Infinite Loop in the first box and Suite 45 in the second box, PHP and Rails will show ["1 Infinite Loop", "Suite 45"] as the contents of the address parameter.
This is all related to the name attribute. On the other hand, the id attribute is designed to uniquely represent an element on the page. It can be referenced using CSS using #myId and in raw JavaScript using document.getElementById. Because it is unique, looking it up in JavaScript is very fast. In practice, you would use jQuery or another library, which would hide these details from you.
It is reasonably common for people to use the same attribute value for id and name, but the only one you need to care about for form submission is name. The jQuery Form Plugin emulates browser behavior extremely closely, so the same would apply to ajaxSubmit.
It's the way forms work in HTML.
Besides, Id's won't work for checkboxes and radio buttons, because you'll probably have several controls with the same name (but a different value), while an HTML element's id attribute has to be unique in your document.
If you really wanted, you could create a preprocessor javascript function that sets every form element's name to the id value, but that wouldn't be very smart IMHO.
var name = $("#contact-name").val();
var email = $("#contact-email").val();
$.post("page.php", { contact-name: name, contact-email: email } );
This will let you post the form with custom attributes.