zulip/docs/subsystems/input-pills.md

UI: input pills

This is a high level and API explanation of the input pill interface in the frontend of the Zulip web application.

Setup

A pill container should have the following markup:

<div class="pill-container">
    <div class="input" contenteditable="true"></div>
</div>

The pills will automatically be inserted in before the ".input" in order.

Basic usage

var $pill_container = $("#input_container");
var pills = input_pill.create({
    $container: $pill_container,
    create_item_from_text: user_pill.create_item_from_email,
    get_text_from_item: user_pill.get_email_from_item,
});

You can look at web/src/user_pill.ts to see how the above methods are implemented. Essentially you just need to convert from raw data (like an email) to structured data (like an object with display_value, email, and user_id for a user), and vice versa. The most important field to supply is display_value. For user pills pill_item.display_value === user.full_name.

Typeahead

Pills almost always work in conjunction with typeahead, and you will want to provide a source function to typeahead that can exclude items from the prior pills. Here is an example snippet from our user group settings code.

source: function () {
    return user_pill.typeahead_source(pills);
},

And then in user_pill.ts...

export function typeahead_source(pill_widget) {
    const persons = people.get_realm_users();
    return filter_taken_users(persons, pill_widget);
}

export function filter_taken_users(items, pill_widget) {
    const taken_user_ids = get_user_ids(pill_widget);
    items = items.filter((item) => !taken_user_ids.includes(item.user_id));
    return items;
}

onPillCreate and onPillRemove methods

You can get notifications from the pill code that pills have been created/remove.

pills.onPillCreate(function () {
    update_save_state();
});

pills.onPillRemove(function () {
    update_save_state();
});