This fixes many of the speed issues the results had when working
with large data sets. jQuery has been completely dropped, with the
exception of setting the data, which does not require a jQuery
object but instead works directly with the DOM. This does not
include options with children, which still uses jQuery to deal
with the nested objects.
This only works with IE 8+, which is fine.
This fixes caching when querying, so the data object no longer
needs to be completely regenerated whenever the `<option>` is
queried.
While this does not fix the speed issues on the first opening of
the instance, it does fix the speed issues during searching.
This improves the speeds of creating the `<option>` tags for array
data. By creating the HTML ahead of time and putting it into an
`<option>` element before passing it to jQuery, it cuts down on the
time it takes for jQuery to process the HTML string and convert it
into DOM elements. This proved to be incredibly slow.
This also changes the `item` function to return early when the
data exists. The `$e.data` call has also been switched to a
`$.data` call, which doesn't need to check the DOM to see if the
data attributes already exist. This cuts down on a bit of wasted
time, as the `data` key should never be present in the DOM, and it
should be ignored if it is.
Now the options are mostly generated by hand before being passed
off to jQuery for templating. This fixes much of the speed issues
we had when they were entirely being generated through jQuery.
This converts individual objects passed in through the `array`
parameter to `<option>` tags when Select2 is initialized. This
removes a lot of duplicate code from the `ArrayAdapter`, and keeps
everything closer to the native `<select>` element.
This introduces a breaking change from previous versions of Select2,
where the initial value for array data was blank, even if a blank
option was not present in the original array of objects. Now the
first object passed in will be selected by default, following the
behavior of a standard `<select>` element.
This breaking change does not affect `<select multiple="multiple">`
elements, which by default have no selection.
The matcher example now matches the old matcher example, and the
compatibility module has been turned into a function decorator
instead of a class decorator.
Only show the "No results found" message when there are no results
visible in the list. This avoid issues when loading more data, and
it returns no results.
Only try to see if the load more button is visible if it is present
in the DOM. This prevents making continuous requests when there are
no more results.
This starts work on the example, which currently uses the GitHub
API.
The `ajax.delay` option has been added that allows for debouncing
requests made within a certain number of milliseconds.
This allows for any control to emit key events, and for the Select2
instance to handle them. So now the search box will allow for
results to be scrolled and selected, bringing back the old expected
functionality. This also stops triggering new queries when the
arrow keys are pressed.
The container will also be automatically focused when the dropdown
is closed, which is consistent with the old Select2.
The results will no longer be queried on initialization, but
instead will be queried when the dropdown is opened. This is more
consistent with the previous version of Select2.
The search box will now be cleared when the dropdown is closed.
The placeholder will not only be automatically hidden if the
results adapter was not already overridden. This will allow users
to override the results adapter to now hide the placeholder, if
they do not want that functionality.
This allows them to be overridden, allowing for things like
attaching the dropdown to a different part of the DOM.
The id is also now generated in a function that can be overridden.
Now that `define` and `require` are never made public, we have to
build everything to support `$.fn.select2.amd` while also working
with other AMD loaders.
This will prevent leaking variables, and will remove the possibility
of Select2 not working well with other plugins which support
AMD loaders. The `define` and `require` methods are now aliased
under `$.Select2.amd` for use inside additional files, such as
translations.
Tags no longer takes an array, as pre-existing tags should already
exist as options in the data adapter. A compatibility module will
later be added to convert tag data that is passed in to array data.
Tags allow for users to enter their own options, which will be
added to the beginning of the results list.
When using array data, and an option is selected, the data that is
attached to the DOM element will be run through `item` and should
have any private, automatically generated attributes added and
merged with it.
Now the accessibility for the single select box better matches what
is picked up for a native select.
This fixes an issue with us always setting `aria-activedescendant`,
which caused Orca to always say the full path to the selected
result, instead of saying that the box was a combobox with a
selection. This means that the `aria-activedescendant` attribute
will now only be set when the dropdown is open.
This also switches the results list from a listbox to a tree, which
is what Firefox tells screen readers that a standard select is.
Combined with a change to use `role=group` and `aria-label` for
option group labels, screen readers will now announce the group
that they are in as well.
We should only be checking the option values that matter, such as
`id` and `text`, instead of checking all of the option values. This
will prevent unexpected breaking when new properties are added to
the options.
Existing properties should be covered by tests to avoid regressions.
Now the Select2 instance is correctly recognized as a combobox, and
the selected option is read aloud when it is focused, just like in
a standard select box.
This works by generating semi-random ids that are used for the
ARIA attributes. These are not intended to be consistent by any
means, they are just generated to make the instance accessible by
screen readers.
When the main container is focused, you can now move the highlighted
result by using the up and down arrows on the keyboard.
This does not yet keep the highlighted result visible at all times,
and it only is implemented on single selects, but that will come in
the future.
This makes quite a few changes, one of the major ones being the
removal of classes for marking options as selected or selectable,
and instead using the ARIA attributes which should already be
present.
Placeholder support has been implemented as a separate module, so
any selection container should be able to be decorated and get
instant placeholder support. It hooks into the updating method of
selections, and determines when to display the placeholder based
on the options that are being updated.
It works in the same way as the old placeholders. If no options
are selected and being displayed, like in the case of a multiple
select, then the placeholder will always be shown. If one option
is being displayed, and the id of the placeholder matches the id
of the selected element, then the placeholder will be shown. This
is similar to the functionality that was present in Select2 2.x,
where the placeholder could be passed in as an object that would
be compared to the selection.
This still requires that, for single selects, the first element
must match the placeholder id. Because the default placeholder id
is a blank string, this will maintain backwards compatibility with
past versions where the first option should be blank. This can
still be overridden to point at a different id, keeping support
for systems where the placeholder doesn't use a blank value.
**Note:** This does not hide the blank option for single selects,
but that will still be maintained for backwards compatibility
within the results module. It will not depend on a placeholder
being present, but instead will hide any options with blank text.
We have to enforce ids being strings as the values of options within
a select will always be an id. This fixes an issue that we had with
array selections not being highlighted in the results.
