Tooltip

Tooltip add additional information on one or more elements.

Overview

Things to know when using the tooltip plugin:

  • Tooltips rely on the 3rd party library Popper.js for positioning. You must include popper.min.js before library loading which contains Popper.js in order for tooltips to work!
  • Tooltips are opt-in for performance reasons, so you must initialize them yourself.
  • Tooltips with zero-length titles are never displayed.
  • Specify container: 'body' to avoid rendering problems in more complex components (like our input groups, button groups, etc).
  • Triggering tooltips on hidden elements will not work.
  • Tooltips for .disabled or disabled elements must be triggered on a wrapper element.
  • When triggered from hyperlinks that span multiple lines, tooltips will be centered. Use white-space: nowrap; on your ` to avoid this behavior.
  • Tooltips must be hidden before their corresponding elements have been removed from the DOM.

Example: Enable tooltips everywhere

One way to initialize all tooltips on a page would be to select them by their data-toggle attribute:

const tooltips = document.querySelectorAll('[data-toggle="tooltip"]');
for (let i = 0; i < tooltips.length; i++) {
  new Tooltip(tooltips[i], {container:tooltips[i]});
}

Examples

Use only the tag <nj-tooltip></nj-tooltip> with the version 3.1 or higher and only in Angular, React or VueJs frameworks.
If you are using an older version or any JavaScript frameworks, do not use this tag and keep only the HTML inside.
<div class="mb-4">
  <nj-tooltip>
    <button type="button" class="nj-btn nj-btn--primary" data-toggle="tooltip" data-placement="top" title="Tooltip on top">
      Tooltip on top
    </button>
  </nj-tooltip>
  <nj-tooltip>
    <button type="button" class="nj-btn nj-btn--primary" data-toggle="tooltip" data-placement="right" title="Tooltip on right">
      Tooltip on right
    </button>
  </nj-tooltip>
  <nj-tooltip>
    <button type="button" class="nj-btn nj-btn--primary" data-toggle="tooltip" data-placement="bottom" title="Tooltip on bottom">
      Tooltip on bottom
    </button>
  </nj-tooltip>
  <nj-tooltip>
    <button type="button" class="nj-btn nj-btn--primary" data-toggle="tooltip" data-placement="left" title="Tooltip on left">
      Tooltip on left
    </button>
  </nj-tooltip>
</div>
<div>
  <nj-tooltip>
    <button type="button" class="nj-btn nj-btn--primary" data-arrow="false" data-toggle="tooltip" data-placement="bottom" title="Tooltip without arrow">
      Tooltip without arrow
    </button>
  </nj-tooltip>
  <nj-tooltip>
    <button type="button" class="nj-btn nj-btn--primary" data-toggle="tooltip" data-html="true" title="<em>Tooltip</em> <u>with</u> <b>HTML</b>">
      Tooltip with HTML
    </button>
  </nj-tooltip>
</div>

Usage

The tooltip plugin generates content and markup on demand, and by default places tooltips after their trigger element.

Trigger the tooltip via JavaScript:

new Tooltip(document.getElementById('tooltip'), options);

Overflow auto and scroll

Tooltip position attempts to automatically change when a parent container has overflow: auto or overflow: scroll, but still keeps the original placement’s positioning. To resolve, set the boundary option to anything other than default value, 'scrollParent', such as 'window':

new Tooltip(document.getElementById('tooltip'), { boundary: 'window' });

Markup

The required markup for a tooltip is only a data attribute and title on the HTML element you wish to have a tooltip. The generated markup of a tooltip is rather simple, though it does require a position (by default, set to top by the plugin).

<!-- HTML to write -->
<nj-tooltip>
  <a href="#" data-toggle="tooltip" title="Some tooltip text!">Hover over me</a>
</nj-tooltip>

<!-- Generated markup by the plugin -->
<div class="tooltip nj-tooltip--top" role="tooltip">
  <div class="nj-tooltip__arrow"></div>
  <div class="nj-tooltip__inner">
    Some tooltip text!
  </div>
</div>

Keyboard and assistive technology users

You should only add tooltips to HTML elements that are traditionally keyboard-focusable and interactive (such as links or form controls). Although arbitrary HTML elements (such as <span>) can be made focusable by adding the tabindex="0" attribute, this will add potentially annoying and confusing tab stops on non-interactive elements for keyboard users. In addition, most assistive technologies currently do not announce the tooltip in this situation.

Additionally, do not rely solely on hover as the trigger for your tooltip, as this will make your tooltips impossible to trigger for keyboard users.

Disabled elements

Elements with the disabled attribute aren’t interactive, meaning users cannot focus, hover, or click them to trigger a tooltip (or popover). As a workaround, you’ll want to trigger the tooltip from a wrapper <div> or <span>, ideally made keyboard-focusable using tabindex=”0”, and override the pointer-events on the disabled element.

<span class="d-inline-block" tabindex="0" data-toggle="tooltip" title="Disabled tooltip">
  <button class="nj-btn nj-btn--primary" style="pointer-events: none;" type="button" disabled>Disabled button</button>
</span>

Options

Options can be passed via data attributes or JavaScript. For data attributes, append the option name to data-, as in data-animation="".

Name Type Defaults Description
animation boolean true Apply a CSS fade transition to the tooltip
container string | element | false false Appends the tooltip to a specific element. Example: container: 'body'. This option is particularly useful in that it allows you to position the tooltip in the flow of the document near the triggering element - which will prevent the tooltip from floating away from the triggering element during a window resize.
delay number | object 0 Delay showing and hiding the tooltip (ms) - does not apply to manual trigger type
If a number is supplied, delay is applied to both hide/show
Object structure is: delay: { "show": 500, "hide": 100 }
html boolean false Allow HTML in the tooltip.
If true, HTML tags in the tooltip’s title will be rendered in the tooltip.
Use text if you’re worried about XSS attacks.
placement string | function ‘top’ How to position the tooltip - auto | top | bottom | left | right.
When auto is specified, it will dynamically reorient the tooltip.
When a function is used to determine the placement, it is called with the tooltip DOM node as its first argument and the triggering element DOM node as its second. The this context is set to the tooltip instance.
selector string | false false If a selector is provided, tooltip objects will be delegated to the specified targets. In practice, this is used to enable dynamic HTML content to have popovers added.
template string ‘hover focus’ How tooltip is triggered - click | hover | focus | manual. You may pass multiple triggers; separate them with a space.
'manual' indicates that the tooltip will be triggered programmatically via the tooltip.show(), tooltip.hide() and tooltip.toggle() methods; this value cannot be combined with any other trigger.
'hover' on its own will result in tooltips that cannot be triggered via the keyboard, and should only be used if alternative methods for conveying the same information for keyboard users is present.
offset string | array ‘flip’ Allow to specify which position Popper will use on fallback. For more information refer to Popper.js’s behavior docs
boundary string | element ‘scrollParent’ Overflow constraint boundary of the tooltip. Accepts the values of 'viewport', 'window', 'scrollParent', or an HTMLElement reference (JavaScript only). For more information refer to Popper.js’s preventOverflow docs.

Methods

Asynchronous methods and transitions All API methods are asynchronous and start a transition. They return to the caller as soon as the transition is started but before it ends. In addition, a method call on a transitioning component will be ignored.
Method Description
show Reveals an element’s tooltip. Returns to the caller before the tooltip has actually been shown (i.e. before the shown.nj.tooltip event occurs). This is considered a “manual” triggering of the tooltip. Tooltips with zero-length titles are never displayed.
hide Hides an element’s tooltip. Returns to the caller before the tooltip has actually been hidden (i.e. before the hidden.nj.tooltip event occurs). This is considered a “manual” triggering of the tooltip.
toggle Toggles an element’s tooltip. Returns to the caller before the tooltip has actually been shown or hidden (i.e. before the shown.nj.tooltip or hidden.nj.tooltip event occurs). This is considered a “manual” triggering of the tooltip.
dispose Hides and destroys an element’s tooltip. Tooltips that use delegation (which are created using the selector option) cannot be individually destroyed on descendant trigger elements.
enable Gives an element’s tooltip the ability to be shown. Tooltips are enabled by default.
disable Removes the ability for an element’s tooltip to be shown. The tooltip will only be able to be shown if it is re-enabled.
toggleEnabled Toggles the ability for an element’s tooltip to be shown or hidden.
update Updates the position of an element’s tooltip.

Events

Event Type Description
show.nj.tooltip This event fires immediately when the show instance method is called.
shown.nj.tooltip This event is fired when the tooltip has been made visible to the user (will wait for CSS transitions to complete).
hide.nj.tooltip This event is fired immediately when the hide instance method has been called.
hidden.nj.tooltip This event is fired when the tooltip has finished being hidden from the user (will wait for CSS transitions to complete).
inserted.nj.tooltip This event is fired after the show.nj.tooltip event when the tooltip template has been added to the DOM.
document.querySelector('#myTooltip').addEventListener('hidden.nj.tooltip', () => {
  // do something...
});