We introduced a bug in commit acbd1b023.
When editing a record and removing an existing image, we don't remove
the HTML fields associated with that image but simply hide them, and
then we add fields to create a new image when clicking on "Add image".
This is standard cocoon behavior. However, since in the case of images
there's a `has_one` relation, cocoon doesn't add unique identifiers to
the new fields, generating duplicate IDs, which is invalid HTML.
Since there's a duplicate file input ID, clicking on the "Choose image"
label we aren't clicking on the new input but on the old one. This means
we aren't correctly attaching an image. The tests passed because
Capybara uses the equivalent of a keyboard to select the field, and in
this case everything worked properly.
So we need to delete the existing elements before inserting new ones.
We're adding a test to check there aren't duplicate IDs.
We were hiding the file input and styling the label as a button instead.
Since clicking on a label has the same effect as clicking on the input,
the input worked properly for mouse and touch screen users.
However, hiding the input makes it inaccessible for keyboard users,
since labels don't get keyboard focus, but inputs do.
So we must not hide the input but make it invisible instead. But we
still need to hide the input (alongside the label) after a file has been
attached.
We could add some extra JavaScript to hide the input when we hide the
label. Since the JavaScript is already quite complex and my first few
attempts at changing it failed, I've opted to assume that the input (and
its label) must be hidden whenever there's already a file name, and
implement that rule with CSS.
Note we're using the `:focus-within` pseudoclass to style a label when
focus is on the input. This rule (at the time of writing) is only
supported by 93.5% of the browsers. Keyboard users without a screen
reader and using the other 6.5% of the browsers will still be able to
focus on the field but might not notice the field has received focus.
Since the percentage of affected users will decrease over time and until
now 100% of keyboard users were completely unable to focus on these
fields, for now we think this is a good-enough solution.
We were already defining the links with data-remote and data-method, so
instead of manually doing an AJAX request we can rely on Rails to
perform the request and then handle the `ajax:complete` event.
This way screen reader users will hear the name of the file before
hearing about the link to destroy it. We were already displaying it this
way visually by having the file name on the left and the destroy link on
the right.
Thanks to this change we can also simplify the code which dynamically
changed the layout.
Since elements are created and destroyed, we don't have to do any kind
of "reset" before destroying or creating them. We would have to do so if
we were just hiding the elements in order to show them again later, but
that's not the case.
Using `dom_id` means generating `new_document` as ID for new documents.
Since there might be more than one new document in the form, that means
duplicate IDs, which is invalid HTML.
Even though this issue doesn't affect image fields (because we don't
have many images on the same form), we're removing the ID there as well
for consistency.
These labels weren't associated with any fields, which is invalid HTML.
We're using a legend inside a fieldset instead, which is the natural way
to group form fields together.
The imageable/documentable object is always the object the form builder
is based on; since we're already passing the form builder, we don't have
to pass the object as well.
The only exception are the poll answers. In this case, we're passing a
new answer as the object. That's OK; the same hack that we're using to
send the data to the answer URL without displaying existing attachments
causes the form to keep working the same way.
We were using long, unique names because these methods used to be helper
methods. Helper methods should have unique names because otherwise one
method would overwrite the other.
Now that we're using components, we can omit the `image_` and
`document_` prefixes.
We've deprecated the "icons" font since we started using Font Awesome
two years ago and using it caused some screen readers to announce an "l"
before the content of every list item.
Since we're going to reuse this pattern in other forms, we shouldn't
rely on the header having just one element. There could be a subtitle.
So we're changing the CSS to be less dependent on a very specific HTML
structure.
Regarding the subtitle, the original idea was to have both an <h1> and
an <h2> element inside the header. However, the W3C advices against it
[1]:
> h1–h6 elements must not be used to markup subheadings, subtitles,
> alternative titles and taglines unless intended to be the heading for
> a new section or subsection.
So we ended up including the subtitle inside he <h1>. We could also add
it in a separate <p> tag. However, in this case I think it's better to
include it in the <h1> (and in the <title> tag) because it helps to
uniquely identify the current page from other pages.
Due to some rounding issues in Firefox, we're manually moving the polygon
6px so there isn't a blank space between it and the icon on the right.
And due to rounding issues in Chrome, we're adding one extra pixel to
the bottom of the polygon defining the clip-path.
[1] https://www.w3.org/TR/html52/common-idioms-without-dedicated-elements.html#common-idioms-without-dedicated-elements
So we don't add the same lines to pretty much every stylesheet we
create.
Eventually we'll remove this code and add a padding to every <main>
element, or (even better) to the <body> element itself.
In commit 49b406199 we added an extra `<span>` element just so we could
add an icon to the right while maintaining both the title and subtitle
on the left.
We can do the same thing without the extra `<span>` element, absolutely
positioning the element and leaving enough padding.
We had an additional `<div>` just to add a background color, when we can
do it by applying the background color to the whole `<main>` element and
then the body background color to the optional fields.
However, I've decided not to do so. The main purpose of changing the
background color is to highlight the required fields. The benefits of
changing the background color of the header as well are unclear. When in
doubt, we're using the solution which requires less code.
The `icon-budget` hasn't been used in this context for a long time;
maybe since commit d0b8fef6b.
The `document-form` class was removed in commit 6c1d828a6.
Finally, the `topic-new` and `topic-form` were removed in commit
c887cb736.
Now the padding is only applied in two places (administration forms) so
we can apply it just there instead of applying it everywhere and then
removing it in most places. We're using the `column` class here because
it's what's used in the rest of the fields of these forms and because we
haven't defined (yet) general margin/padding rules for the
administration views.