This commit adds a new page, which appears after a user enters the name for
their new service. It shows how the service name will appear in emails and
text messages.
This means that the new service is not created until after they have confirmed
that the name is appropriate in context.
This has also involved:
- visual changes to the ‘email template’ pattern, which wasn’t very refined
before
- removing a bunch of words from the enter service name page, because most users
don’t read them, and we reckon that showing a preview is a better way of
getting them to understand what is meant by service name
Still to do:
- validating the the generated email address for a service is unique (on the
API) side
- having the API return the generated email address, rather than determining it
in the admin app
This involves:
- removing the hard coded width on any textbox that does placeholder
highlighting
- adding JS to make sure that the extra layers on top of the textbox inherit
the width of the textbox that the user types in (so the layers don’t get
misaligned)
Keeping the textboxes at 2/3 width for consistency with how wide the messages
are on the ‘manage templates’ page.
The grouping on this page was weird because these links were two far away from
the associated textbox, and too close to the next textbox.
This commit adds them as parameters to the textbox macro, which means their
relative spacing can be controlled exactly, and thus reduced.
Users can add placeholders to their messages, eg
> …your vehicle ((registration number))
when the message is sent, this gets replaced with the data the user uploads, eg
> …your vehicle LC12 BFL
We reckon that it will be useful to see that the placeholder has been
recognised, ie that its syntax is correct, before uploading any data.
We reckon that the best way to do this is by styling it differently to the rest
of the text that the user types.
This is not a trivial problem. There are two possible ways to do it:
1 Write a Google Docs-style text rendering engine, which completely replaces
the native HTML `<textarea>` with a custom control, and programme what should
happen when the user types something that looks like a placeholder, or
presses an arrow key, or makes a selection, or…
2 Leave the `<textarea>` in place, unmodified, and duplicate layers in front
of/behind it to visually replace a placeholder with the blue lozenge
Unsurprisingly, this commit implements 2.
There are four layers. Each layer contains live-updated copy of the text in the
textbox, and each is styled differently:
- one layer behind the textbox to make the blue background
- the textbox itself
- a layer with the white text, which overlays the black text of the textbox
- a layer with an inner shadow to knock back the brackets
This is because of some interesting limitations:
- The text in the foreground and background must occupy the same physical space,
so no deleting characters from the duplicated layers
- Words can’t be split up into multiple elements,
eg `<span>((</span>regist…`:—this results in slightly different kerning to
`((regis…`, which messes up the alignment of the layers
- The textbox can’t be completely overlapped with a block of colour, because
the cursor disappears behind it. Trying to edit text when you can’t see the
cursor is hard.
Implementation
Technically this makes use of Paul Hayes work on Javascript modules in the
GOV.UK frontend toolkit[1].
It also makes use of the `oninput` event to detect changes to the textbox’s
contents. This is much more performant than `onkeydown`, `onpaste`, etc. Without
it the delay between user input and the layers all updating is too slow and you
see misalignment of the layers.
1. https://github.com/alphagov/govuk_frontend_toolkit/pull/227
