svelte-multiselect

 Svelte MultiSelect

Live demo.

Keyboard-friendly, zero-dependency multi-select Svelte component.

Key Features

• Single / multiple select: pass maxSelect={1} prop to only allow one selection
• Dropdowns: scrollable lists for large numbers of options
• Searchable: start typing to filter options
• Tagging: selected options are recorded as tags in the input
• Server-side rendering: no reliance on browser objects like window or document
• Configurable: see props
• No dependencies: needs only Svelte as dev dependency
• Keyboard friendly for mouse-less form completion

Recent breaking changes

• v2.0.0 added the ability to pass options as objects. As a result, bind:selected no longer returns simple strings but objects, even if you still pass in options as strings. To get the same stuff you would have gotten from bind:selected before, there's now bind:selectedLabels (and bind:selectedValues).

• v3.0.0 changed the event.detail payload for 'add', 'remove' and 'change' events from token to option, e.g.

  on:add={(e) => console.log(e.detail.token.label)} // v2.0.0
  on:add={(e) => console.log(e.detail.option.label)} // v3.0.0
  

  It also added a separate event type removeAll for when the user removes all currently selected options at once which previously fired a normal remove. The props ulTokensClass and liTokenClass were renamed to ulSelectedClass and liSelectedClass. Similarly, the CSS variable --sms-token-bg changed to --sms-selected-bg.

Installation

yarn add -D svelte-multiselect

Usage

<script>
  import MultiSelect from 'svelte-multiselect'

  const webFrameworks = [
    `Svelte`,
    `React`,
    `Vue`,
    `Angular`,
    `Polymer`,
    `Ruby on Rails`,
    `ASP.net`,
    `Laravel`,
    `Django`,
    `Express`,
    `Spring`,
  ]

  let selected
</script>

Favorite Web Frameworks?

<code>selected = {JSON.stringify(selected)}</code>

<MultiSelect bind:selected options={webFrameworks} />

Props

Full list of props/bindable variables for this component:

name	default	description
options	required prop	Array of strings/numbers or Option objects that will be listed in the dropdown. See src/lib/index.ts for admissible fields. The label is the only mandatory one. It must also be unique.
activeOption	null	Currently active option, i.e. the one the user currently hovers or navigated to with arrow keys.
maxSelect	null	Positive integer to limit the number of options users can pick. null means no limit.
maxSelectMsg	(current: number, max: number) => `${current}/${max}`	Function that returns a string informing the user how many of the maximum allowed options they have currently selected. Return empty string to disable, i.e. () => ''.
selected	[]	Array of currently/pre-selected options when binding/passing as props respectively.
selectedLabels	[]	Labels of currently selected options.
selectedValues	[]	Values of currently selected options.
readonly	false	Disable the component. It will still be rendered but users won't be able to interact with it.
placeholder	undefined	String shown in the text input when no option is selected.
input	undefined	Handle to the <input> DOM node.
id	undefined	Applied to the <input> element for associating HTML form <label>s with this component for accessibility. Also, clicking a <label> with same for attribute as id will focus this component.
name	id	Applied to the <input> element. If not provided, will be set to the value of id. Sets the key of this field in a submitted form data object. Not useful at the moment since the value is stored in Svelte state, not on the <input>.

Slots

MultiSelect.svelte accepts two named slots

• slot="renderOptions"
• slot="renderSelected"

to customize rendering individual options in the dropdown and the list of selected tags, respectively. Each renderer receives the full option object along with the zero-indexed position (idx) in its list, both available via the let: directive:

<MultiSelect options={[`Banana`, `Apple`, `Mango`]}>
  <span let:idx let:option slot="renderOptions">
    {idx + 1}. {option.label}
    {option.label === `Mango` ? `🎉` : ``}
  </span>

  <span let:idx let:option slot="renderSelected">
    #{idx + 1}
    {option.label}
  </span>
</MultiSelect>

Events

MultiSelect.svelte dispatches the following events:

name	detail	description
add	{ option: Option }	Triggers when a new option is selected.
remove	{ option: Option }	Triggers when one selected option provided as event.detail.option is removed.
removeAll	options: Option[]	Triggers when all selected options are removed. The payload event.detail.options gives the options that were previously selected.
change	{ option?: Option, options?: Option[] }, type: 'add' | 'remove' | 'removeAll'	Triggers when a option is either added or removed, or all options are removed at once.
blur	none	Triggers when the input field looses focus.

Examples

• on:add={(event) => console.log(event.detail.option.label)}
• on:remove={(event) => console.log(event.detail.option.label)}.
• on:change={(event) => console.log(`${event.detail.type}: '${event.detail.option.label}'`)}
• on:blur={yourFunctionHere}

<MultiSelect
  on:change={(e) => alert(`You ${e.detail.type}ed '${e.detail.option.label}'`)}
/>

TypeScript

TypeScript users can import the types used for internal type safety:

<script lang="ts">
  import MultiSelect, {
    Option,
    Primitive,
    ProtoOption,
  } from 'svelte-multiselect'

  const myOptions: Option[] = [
    { label: 'foo', value: 42 },
    { label: 'bar', value: 69 },
  ]
</script>

Styling

There are 3 ways to style this component. To understand which options do what, it helps to keep in mind this simplified DOM structure of the component:

<div class="multiselect">
  <ul class="selected">
    <li>Selected 1</li>
    <li>Selected 2</li>
  </ul>
  <ul class="options">
    <li>Option 1</li>
    <li>Option 2</li>
  </ul>
</div>

With CSS variables

If you only want to make small adjustments, you can pass the following CSS variables directly to the component as props or define them in a :global() CSS context.

• div.multiselect:
  • border: var(--sms-border, 1pt solid lightgray): Change this to e.g. to 1px solid red to indicate this form field is in an invalid state.
  • border-radius: var(--sms-border-radius, 5pt): Input border radius.
  • background: var(--sms-input-bg): Input background.
  • height: var(--sms-input-height, 2em): Input height.
  • border: var(--sms-focus-border, 1pt solid var(--sms-active-color, cornflowerblue)): Border when focused. Falls back to --sms-active-color if not set which in turn falls back on cornflowerblue.
  • background: var(--sms-readonly-bg, lightgray): Background when in readonly state.
• div.multiselect.open:
  • z-index: var(--sms-open-z-index, 4): Useful to ensure the dropdown list of options is displayed on top of other page elements of increased z-index.
• div.multiselect input
  • color: var(--sms-text-color, inherit): Input text color.
• ul.selected > li:
  • background: var(--sms-selected-bg, var(--sms-active-color, cornflowerblue)): Background of selected options.
• ul.selected > li button:hover, button.remove-all:hover
  • color: var(--sms-remove-x-hover-focus-color, lightskyblue): Color of the cross-icon buttons for removing all or individual selected options when in :focus or :hover state.
• ul.options
  • background: var(--sms-options-bg, white): Background of options list.
• ul.options > li.selected
  • background: var(--sms-li-selected-bg, inherit): Background of selected list items in options pane.
  • color: var(--sms-li-selected-color, inherit): Text color of selected list items in options pane.
• ul.options > li.active
  • background: var(--sms-li-active-bg, var(--sms-active-color, cornflowerblue)): Background of active (currently with arrow keys highlighted) list item.
• ul.options > li.disabled
  • background: var(--sms-li-disabled-bg, #f5f5f6): Background of disabled options in the dropdown list.
  • color: var(--sms-li-disabled-text, #b8b8b8): Text color of disabled option in the dropdown list.

For example, to change the background color of the options dropdown:

<MultiSelect --sms-options-bg="white" />

With CSS frameworks

The second method allows you to pass in custom classes to the important DOM elements of this component to target them with frameworks like Tailwind CSS.

• outerDivClass
• ulSelectedClass
• liSelectedClass
• ulOptionsClass
• liOptionClass

This simplified version of the DOM structure of this component shows where these classes are inserted:

<div class="multiselect {outerDivClass}">
  <ul class="selected {ulSelectedClass}">
    <li class={liSelectedClass}>Selected 1</li>
    <li class={liSelectedClass}>Selected 2</li>
  </ul>
  <ul class="options {ulOptionsClass}">
    <li class={liOptionClass}>Option 1</li>
    <li class={liOptionClass}>Option 2</li>
  </ul>
</div>

Granular control through global CSS

You can alternatively style every part of this component with more fine-grained control by using the following :global() CSS selectors. ul.selected is the list of currently selected options rendered inside the component's input whereas ul.options is the list of available options that slides out when the component has focus.

:global(.multiselect) {
  /* top-level wrapper div */
}
:global(.multiselect ul.selected > li) {
  /* selected options */
}
:global(.multiselect ul.selected > li button),
:global(.multiselect button.remove-all) {
  /* buttons to remove a single or all selected options at once */
}
:global(.multiselect ul.options) {
  /* dropdown options */
}
:global(.multiselect ul.options li) {
  /* dropdown list of available options */
}
:global(.multiselect ul.options li.selected) {
  /* selected options in the dropdown list */
}
:global(.multiselect ul.options li:not(.selected):hover) {
  /* unselected but hovered options in the dropdown list */
}
:global(.multiselect ul.options li.selected:hover) {
  /* selected and hovered options in the dropdown list */
  /* probably not necessary to style this state in most cases */
}
:global(.multiselect ul.options li.active) {
  /* active means item was navigated to with up/down arrow keys */
  /* ready to be selected by pressing enter */
}
:global(.multiselect ul.options li.selected.active) {
  /* both active and already selected, pressing enter now will deselect the item */
}
:global(.multiselect ul.options li.disabled) {
  /* options with disabled key set to true (see props above) */
}

Want to contribute?

To submit a PR, clone the repo, install dependencies and start the dev server to try out your changes.

git clone https://github.com/janosh/svelte-multiselect
cd svelte-multiselect
yarn
yarn dev

Changelog

v3.2.0

3 February 2022

• apply id prop to <input> insted of outer div (closes #25) #25
• add eslint commit hook + update deps 6ad44b8
• v.3.2.0 71ff2d1
• add readme badge to document minimum svelte version (for #24) 7d9fe5a