Popup
<wa-popup>
Popups declaratively anchor one element to another and keep them positioned together as the page scrolls or resizes. Primarily a low-level building block for popovers, dropdowns, and tooltips.
This component's name is inspired by <popup>. It uses Floating UI under the hood to provide a well-tested, lightweight, and fully declarative positioning utility for tooltips, dropdowns, and more.
Popup doesn't provide any styles — just positioning! The popup's preferred placement, distance, and skidding (offset) can be configured using attributes. An arrow that points to the anchor can be shown and customized to your liking. Additional positioning options are available and described in more detail below.
Popup is a low-level utility built specifically for positioning elements. Do not mistake it for a tooltip or similar because it does not facilitate an accessible experience! Almost every correct usage of <wa-popup> will involve building other components. It should rarely, if ever, occur directly in your HTML.
A popup's anchor should not be styled with display: contents since the coordinates will not be eligible for calculation. However, if the anchor is a <slot> element, popup will use the first assigned element as the anchor. This behavior allows other components to pass anchors through more easily via composition.
Examples
Activating
Popups are inactive and hidden until the active attribute is applied. Removing the attribute will tear down all positioning logic and listeners, meaning you can have many idle popups on the page without affecting performance.
External Anchors
By default, anchors are slotted into the popup using the anchor slot. If your anchor needs to live outside of the popup, you can pass the anchor's id to the anchor attribute. Alternatively, you can pass an element reference to the anchor property to achieve the same effect without using an id.
Placement
Use the placement attribute to tell the popup the preferred placement of the popup. Note that the actual position will vary to ensure the panel remains in the viewport if you're using positioning features such as flip and shift.
Since placement is preferred when using flip, you can observe the popup's current placement when it's active by looking at the data-current-placement attribute. This attribute will update as the popup flips to find available space and it will be removed when the popup is deactivated.
Distance
Use the distance attribute to change the distance between the popup and its anchor. A positive value will move the popup further away and a negative value will move it closer.
Skidding
The skidding attribute is similar to distance, but instead allows you to offset the popup along the anchor's axis. Both positive and negative values are allowed.
Arrows
Add an arrow to your popup with the arrow attribute. It's usually a good idea to set a distance to make room for the arrow. To adjust the arrow's color and size, use the --arrow-color and --arrow-size custom properties, respectively. You can also target the arrow part to add additional styles such as shadows and borders to match styles applied to rest of the popup element.
By default, the arrow will be aligned as close to the center of the anchor as possible, considering available space and arrow-padding. You can use the arrow-placement attribute to force the arrow to align to the start, end, or center of the popup instead.
Adding a border
Borders can also be added to the popup element by targeting the contents of the wa-popup element. This styling can also be extended to the arrow itself by targeting .arrow class in the popup.
When adding borders to the popup element which has an arrow, make sure to set the --popup-border-width custom property to match the width of the border of the popup. Setting this will allow the arrow to overlap the border of the popup so that they visually appear connected.
Flip
When the popup doesn't have enough room in its preferred placement, it can automatically flip to keep it in view and visually connected to its anchor.
To enable this, use the flip attribute. By default, the popup will flip to the opposite placement, but you can configure preferred fallback placements using flip-fallback-placement and flip-fallback-strategy. Additional options are available to control the flip behavior's boundary and padding.
By default, flip takes effect when the popup would overflow the viewport.
You can use boundary="scroll" to make the popup resize when it overflows its nearest scrollable container instead.
Scroll the container to see how the popup flips to prevent clipping.
Flip Fallbacks
While using the flip attribute, you can customize the placement of the popup when the preferred placement doesn't have room. For this, use flip-fallback-placements and flip-fallback-strategy.
If the preferred placement doesn't have room, the first suitable placement found in flip-fallback-placement will be used. The value of this attribute must be a string including any number of placements separated by a space, e.g. "right bottom".
If no fallback placement works, the final placement will be determined by flip-fallback-strategy. This value can be either initial (default), where the placement reverts to the position in placement, or best-fit, where the placement is chosen based on available space.
Scroll the container to see how the popup changes it's fallback placement to prevent clipping.
Shift
When a popup is longer than its anchor, it risks overflowing.
In this case, use the shift attribute to shift the popup along its axis and back into view. You can customize the shift behavior using shiftBoundary and shift-padding.
By default, auto-size takes effect when the popup would overflow the viewport.
You can use boundary="scroll" to make the popup resize when it overflows its nearest scrollable container instead.
Toggle the switch to see the difference.
Auto-size
Use the auto-size attribute to tell the popup to resize when necessary to prevent it from overflowing.
Possible values are horizontal, vertical, and both. You can use autoSizeBoundary and auto-size-padding to customize the behavior of this option. Auto-size works well with flip, but if you're using auto-size-padding make sure flip-padding is the same value.
By default, auto-size takes effect when the popup would overflow the viewport.
You can use boundary="scroll" to make the popup resize when it overflows its nearest scrollable container instead.
When using auto-size, one or both of --auto-size-available-width and --auto-size-available-height will be applied to the host element. These values determine the available space the popover has before clipping will occur. Since they cascade, you can use them to set a max-width/height on your popup's content and easily control its overflow.
Scroll the container to see the popup resize as its available space changes.
Hover Bridge
When a gap exists between the anchor and the popup element, this option will add a "hover bridge" that fills the gap using an invisible element. This makes listening for events such as mouseover and mouseout more sane because the pointer never technically leaves the element. The hover bridge will only be drawn when the popover is active. For demonstration purposes, the bridge in this example is shown in orange.
Virtual Elements
In most cases, popups are anchored to an actual element. Sometimes, it can be useful to anchor them to a non-element. To do this, you can pass a VirtualElement to the anchor property. A virtual element must contain a function called getBoundingClientRect() that returns a DOMRect object as shown below.
const virtualElement = { getBoundingClientRect() { // ... return { width, height, x, y, top, left, right, bottom }; }, };
This example anchors a popup to the mouse cursor using a virtual element. As such, a mouse is required to properly view it.
Built-in Animations
The following classes can be applied to the popup's popup part to animate it in or out programmatically. You can control the animation duration with the --show-duration and --hide-duration custom properties.
show/hide- Shows or hides the popover with a fadeshow-with-scale/hide-with-scale- Shows or hides the popover with a fade and subtle scale effect
Importing
If you're using the autoloader or a hosted project, components load on demand — no manual import needed. To cherry-pick a component manually, use one of the following snippets.
Import this component directly from the CDN:
import 'https://ka-f.webawesome.com/[email protected]/components/popup/popup.js';
After installing Web Awesome via npm, import this component:
import '@awesome.me/webawesome/dist/components/popup/popup.js';
If you're self-hosting Web Awesome, import this component from your server:
import './webawesome/dist/components/popup/popup.js';
To import this component for React 18 or below, use the following code:
import WaPopup from '@awesome.me/webawesome/dist/react/popup/index.js';
Slots
Learn more about using slots.
| Name | Description |
|---|---|
| (default) | The popup's content. |
anchor
|
The element the popup will be anchored to. If the anchor lives outside of the popup, you can use the anchor attribute or property instead. |
Attributes & Properties
Learn more about attributes and properties.
| Name | Description | Reflects | |
|---|---|---|---|
activeactive |
Activates the positioning logic and shows the popup. When this attribute is removed, the positioning logic is torn
down and the popup will be hidden.
Type
booleanDefault
false |
|
|
anchoranchor |
The element the popup will be anchored to. If the anchor lives outside of the popup, you can provide the anchor
element
id, a DOM element reference, or a VirtualElement. If the anchor lives inside the popup, use the
anchor slot instead.Type
Element | string | VirtualElement |
||
arrowarrow |
Attaches an arrow to the popup. The arrow's size and color can be customized using the
--arrow-size and
--arrow-color custom properties. For additional customizations, you can also target the arrow using
::part(arrow) in your stylesheet.Type
booleanDefault
false |
||
arrowPaddingarrow-padding |
The amount of padding between the arrow and the edges of the popup. If the popup has a border-radius, for example,
this will prevent it from overflowing the corners.
Type
numberDefault
10 |
||
arrowPlacementarrow-placement |
The placement of the arrow. The default is
anchor, which will align the arrow as close to the center of the
anchor as possible, considering available space and arrow-padding. A value of start, end, or center will
align the arrow to the start, end, or center of the popover instead.Type
'start' | 'end' | 'center' | 'anchor'Default
'anchor' |
||
autoSizeauto-size |
When set, this will cause the popup to automatically resize itself to prevent it from overflowing.
Type
'horizontal' | 'vertical' | 'both' |
||
autoSizeBoundaryautoSizeBoundary |
The auto-size boundary describes clipping element(s) that overflow will be checked relative to when resizing. By
default, the boundary includes overflow ancestors that will cause the element to be clipped. If needed, you can
change the boundary by passing a reference to one or more elements to this property.
Type
Element | Element[] |
||
autoSizePaddingauto-size-padding |
The amount of padding, in pixels, to exceed before the auto-size behavior will occur.
Type
numberDefault
0 |
||
boundaryboundary |
The bounding box to use for flipping, shifting, and auto-sizing.
Type
'viewport' | 'scroll'Default
'viewport' |
||
css |
One or more CSSResultGroup to include in the component's shadow root. Host styles are automatically prepended.
Type
CSSResultGroup | undefinedDefault
styles |
||
distancedistance |
The distance in pixels from which to offset the panel away from its anchor.
Type
numberDefault
0 |
||
flipflip |
When set, placement of the popup will flip to the opposite site to keep it in view. You can use
flipFallbackPlacements to further configure how the fallback placement is determined.Type
booleanDefault
false |
||
flipBoundaryflipBoundary |
The flip boundary describes clipping element(s) that overflow will be checked relative to when flipping. By
default, the boundary includes overflow ancestors that will cause the element to be clipped. If needed, you can
change the boundary by passing a reference to one or more elements to this property.
Type
Element | Element[] |
||
flipFallbackPlacementsflip-fallback-placements |
If the preferred placement doesn't fit, popup will be tested in these fallback placements until one fits. Must be a
string of any number of placements separated by a space, e.g. "top bottom left". If no placement fits, the flip
fallback strategy will be used instead.
Type
stringDefault
'' |
||
flipFallbackStrategyflip-fallback-strategy |
When neither the preferred placement nor the fallback placements fit, this value will be used to determine whether
the popup should be positioned using the best available fit based on available space or as it was initially
preferred.
Type
'best-fit' | 'initial'Default
'best-fit' |
||
flipPaddingflip-padding |
The amount of padding, in pixels, to exceed before the flip behavior will occur.
Type
numberDefault
0 |
||
hoverBridgehover-bridge |
When a gap exists between the anchor and the popup element, this option will add a "hover bridge" that fills the
gap using an invisible element. This makes listening for events such as
mouseenter and mouseleave more sane
because the pointer never technically leaves the element. The hover bridge will only be drawn when the popover is
active.Type
booleanDefault
false |
||
placementplacement |
The preferred placement of the popup. Note that the actual placement will vary as configured to keep the
panel inside of the viewport.
Type
'top'
| 'top-start'
| 'top-end'
| 'bottom'
| 'bottom-start'
| 'bottom-end'
| 'right'
| 'right-start'
| 'right-end'
| 'left'
| 'left-start'
| 'left-end'Default
'top' |
|
|
popup |
A reference to the internal popup container. Useful for animating and styling the popup with JavaScript.
Type
HTMLElement |
||
shiftshift |
Moves the popup along the axis to keep it in view when clipped.
Type
booleanDefault
false |
||
shiftBoundaryshiftBoundary |
The shift boundary describes clipping element(s) that overflow will be checked relative to when shifting. By
default, the boundary includes overflow ancestors that will cause the element to be clipped. If needed, you can
change the boundary by passing a reference to one or more elements to this property.
Type
Element | Element[] |
||
shiftPaddingshift-padding |
The amount of padding, in pixels, to exceed before the shift behavior will occur.
Type
numberDefault
0 |
||
skiddingskidding |
The distance in pixels from which to offset the panel along its anchor.
Type
numberDefault
0 |
||
syncsync |
Syncs the popup's width or height to that of the anchor element.
Type
'width' | 'height' | 'both' |
Methods
Learn more about methods.
| Name | Description | Arguments |
|---|---|---|
reposition() |
Forces the popup to recalculate and reposition itself. |
Events
Learn more about events.
| Name | Description |
|---|---|
wa-reposition |
Emitted when the popup is repositioned. This event can fire a lot, so avoid putting expensive operations in your listener or consider debouncing it. |
CSS custom properties
Learn more about CSS custom properties.
| Name | Description |
|---|---|
--arrow-color |
The color of the arrow.
Default
black
|
--arrow-size |
The size of the arrow. Note that an arrow won't be shown unless the
arrow attribute is used.
Default
6px
|
--auto-size-available-height |
A read-only custom property that determines the amount of height the popup can be before overflowing. Useful for positioning child elements that need to overflow. This property is only available when using
auto-size. |
--auto-size-available-width |
A read-only custom property that determines the amount of width the popup can be before overflowing. Useful for positioning child elements that need to overflow. This property is only available when using
auto-size. |
--hide-duration |
The hide duration to use when applying built-in animation classes.
Default
var(--wa-transition-fast)
|
--popup-border-width |
The width of any custom border applied to the popup. This is used to reposition the arrow to overlap to the inside edge of the popup border.
|
--show-duration |
The show duration to use when applying built-in animation classes.
Default
var(--wa-transition-fast)
|
CSS parts
Learn more about CSS parts.
| Name | Description | CSS selector |
|---|---|---|
arrow |
The arrow's container. Avoid setting top|bottom|left|right properties, as these values are assigned dynamically as the popup moves. This is most useful for applying a background color to match the popup, and maybe a border or box shadow. |
::part(arrow)
|
hover-bridge |
The hover bridge element. Only available when the hover-bridge option is enabled. |
::part(hover-bridge)
|
popup |
The popup's container. Useful for setting a background color, box shadow, etc. |
::part(popup)
|