shoelace/docs/pages/components/dropdown.md

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2023-06-06 12:22:18 +00:00
---
meta:
title: Dropdown
description: 'Dropdowns expose additional content that "drops down" in a panel.'
layout: component
---
Dropdowns consist of a trigger and a panel. By default, activating the trigger will expose the panel and interacting outside of the panel will close it.
Dropdowns are designed to work well with [menus](/components/menu) to provide a list of options the user can select from. However, dropdowns can also be used in lower-level applications (e.g. [color picker](/components/color-picker) and [select](/components/select)). The API gives you complete control over showing, hiding, and positioning the panel.
```html:preview
<sl-dropdown>
<sl-button slot="trigger" caret>Dropdown</sl-button>
<sl-menu>
<sl-menu-item>Dropdown Item 1</sl-menu-item>
<sl-menu-item>Dropdown Item 2</sl-menu-item>
<sl-menu-item>Dropdown Item 3</sl-menu-item>
<sl-divider></sl-divider>
<sl-menu-item type="checkbox" checked>Checkbox</sl-menu-item>
<sl-menu-item disabled>Disabled</sl-menu-item>
<sl-divider></sl-divider>
<sl-menu-item>
Prefix
<sl-icon slot="prefix" name="gift"></sl-icon>
</sl-menu-item>
<sl-menu-item>
Suffix Icon
<sl-icon slot="suffix" name="heart"></sl-icon>
</sl-menu-item>
</sl-menu>
</sl-dropdown>
```
```jsx:react
import { SlButton, SlDivider, SlDropdown, SlIcon, SlMenu, SlMenuItem } from '@shoelace-style/shoelace/dist/react';
const App = () => (
<SlDropdown>
<SlButton slot="trigger" caret>
Dropdown
</SlButton>
<SlMenu>
<SlMenuItem>Dropdown Item 1</SlMenuItem>
<SlMenuItem>Dropdown Item 2</SlMenuItem>
<SlMenuItem>Dropdown Item 3</SlMenuItem>
<SlDivider />
<SlMenuItem type="checkbox" checked>
Checkbox
</SlMenuItem>
<SlMenuItem disabled>Disabled</SlMenuItem>
<SlDivider />
<SlMenuItem>
Prefix
<SlIcon slot="prefix" name="gift" />
</SlMenuItem>
<SlMenuItem>
Suffix Icon
<SlIcon slot="suffix" name="heart" />
</SlMenuItem>
</SlMenu>
</SlDropdown>
);
```
## Examples
### Getting the Selected Item
When dropdowns are used with [menus](/components/menu), you can listen for the [`sl-select`](/components/menu#events) event to determine which menu item was selected. The menu item element will be exposed in `event.detail.item`. You can set `value` props to make it easier to identify commands.
```html:preview
<div class="dropdown-selection">
<sl-dropdown>
<sl-button slot="trigger" caret>Edit</sl-button>
<sl-menu>
<sl-menu-item value="cut">Cut</sl-menu-item>
<sl-menu-item value="copy">Copy</sl-menu-item>
<sl-menu-item value="paste">Paste</sl-menu-item>
</sl-menu>
</sl-dropdown>
</div>
<script>
const container = document.querySelector('.dropdown-selection');
const dropdown = container.querySelector('sl-dropdown');
dropdown.addEventListener('sl-select', event => {
const selectedItem = event.detail.item;
console.log(selectedItem.value);
});
</script>
```
```jsx:react
import { SlButton, SlDropdown, SlMenu, SlMenuItem } from '@shoelace-style/shoelace/dist/react';
const App = () => {
function handleSelect(event) {
const selectedItem = event.detail.item;
console.log(selectedItem.value);
}
return (
<SlDropdown>
<SlButton slot="trigger" caret>
Edit
</SlButton>
<SlMenu onSlSelect={handleSelect}>
<SlMenuItem value="cut">Cut</SlMenuItem>
<SlMenuItem value="copy">Copy</SlMenuItem>
<SlMenuItem value="paste">Paste</SlMenuItem>
</SlMenu>
</SlDropdown>
);
};
```
Alternatively, you can listen for the `click` event on individual menu items. Note that, using this approach, disabled menu items will still emit a `click` event.
```html:preview
<div class="dropdown-selection-alt">
<sl-dropdown>
<sl-button slot="trigger" caret>Edit</sl-button>
<sl-menu>
<sl-menu-item value="cut">Cut</sl-menu-item>
<sl-menu-item value="copy">Copy</sl-menu-item>
<sl-menu-item value="paste">Paste</sl-menu-item>
</sl-menu>
</sl-dropdown>
</div>
<script>
const container = document.querySelector('.dropdown-selection-alt');
const cut = container.querySelector('sl-menu-item[value="cut"]');
const copy = container.querySelector('sl-menu-item[value="copy"]');
const paste = container.querySelector('sl-menu-item[value="paste"]');
cut.addEventListener('click', () => console.log('cut'));
copy.addEventListener('click', () => console.log('copy'));
paste.addEventListener('click', () => console.log('paste'));
</script>
```
```jsx:react
import { SlButton, SlDropdown, SlMenu, SlMenuItem } from '@shoelace-style/shoelace/dist/react';
const App = () => {
function handleCut() {
console.log('cut');
}
function handleCopy() {
console.log('copy');
}
function handlePaste() {
console.log('paste');
}
return (
<SlDropdown>
<SlButton slot="trigger" caret>
Edit
</SlButton>
<SlMenu>
<SlMenuItem onClick={handleCut}>Cut</SlMenuItem>
<SlMenuItem onClick={handleCopy}>Copy</SlMenuItem>
<SlMenuItem onClick={handlePaste}>Paste</SlMenuItem>
</SlMenu>
</SlDropdown>
);
};
```
### Placement
The preferred placement of the dropdown can be set with the `placement` attribute. Note that the actual position may vary to ensure the panel remains in the viewport.
```html:preview
<sl-dropdown placement="top-start">
<sl-button slot="trigger" caret>Edit</sl-button>
<sl-menu>
<sl-menu-item>Cut</sl-menu-item>
<sl-menu-item>Copy</sl-menu-item>
<sl-menu-item>Paste</sl-menu-item>
<sl-divider></sl-divider>
<sl-menu-item>Find</sl-menu-item>
<sl-menu-item>Replace</sl-menu-item>
</sl-menu>
</sl-dropdown>
```
```jsx:react
import { SlButton, SlDivider, SlDropdown, SlMenu, SlMenuItem } from '@shoelace-style/shoelace/dist/react';
const App = () => (
<SlDropdown placement="top-start">
<SlButton slot="trigger" caret>
Edit
</SlButton>
<SlMenu>
<SlMenuItem>Cut</SlMenuItem>
<SlMenuItem>Copy</SlMenuItem>
<SlMenuItem>Paste</SlMenuItem>
<SlDivider />
<SlMenuItem>Find</SlMenuItem>
<SlMenuItem>Replace</SlMenuItem>
</SlMenu>
</SlDropdown>
);
```
### Distance
The distance from the panel to the trigger can be customized using the `distance` attribute. This value is specified in pixels.
```html:preview
<sl-dropdown distance="30">
<sl-button slot="trigger" caret>Edit</sl-button>
<sl-menu>
<sl-menu-item>Cut</sl-menu-item>
<sl-menu-item>Copy</sl-menu-item>
<sl-menu-item>Paste</sl-menu-item>
<sl-divider></sl-divider>
<sl-menu-item>Find</sl-menu-item>
<sl-menu-item>Replace</sl-menu-item>
</sl-menu>
</sl-dropdown>
```
```jsx:react
import { SlButton, SlDivider, SlDropdown, SlMenu, SlMenuItem } from '@shoelace-style/shoelace/dist/react';
const App = () => (
<SlDropdown distance={30}>
<SlButton slot="trigger" caret>
Edit
</SlButton>
<SlMenu>
<SlMenuItem>Cut</SlMenuItem>
<SlMenuItem>Copy</SlMenuItem>
<SlMenuItem>Paste</SlMenuItem>
<SlDivider />
<SlMenuItem>Find</SlMenuItem>
<SlMenuItem>Replace</SlMenuItem>
</SlMenu>
</SlDropdown>
);
```
### Skidding
The offset of the panel along the trigger can be customized using the `skidding` attribute. This value is specified in pixels.
```html:preview
<sl-dropdown skidding="30">
<sl-button slot="trigger" caret>Edit</sl-button>
<sl-menu>
<sl-menu-item>Cut</sl-menu-item>
<sl-menu-item>Copy</sl-menu-item>
<sl-menu-item>Paste</sl-menu-item>
<sl-divider></sl-divider>
<sl-menu-item>Find</sl-menu-item>
<sl-menu-item>Replace</sl-menu-item>
</sl-menu>
</sl-dropdown>
```
```jsx:react
import { SlButton, SlDivider, SlDropdown, SlMenu, SlMenuItem } from '@shoelace-style/shoelace/dist/react';
const App = () => (
<SlDropdown skidding={30}>
<SlButton slot="trigger" caret>
Edit
</SlButton>
<SlMenu>
<SlMenuItem>Cut</SlMenuItem>
<SlMenuItem>Copy</SlMenuItem>
<SlMenuItem>Paste</SlMenuItem>
<SlDivider />
<SlMenuItem>Find</SlMenuItem>
<SlMenuItem>Replace</SlMenuItem>
</SlMenu>
</SlDropdown>
);
```
### Hoisting
Dropdown panels will be clipped if they're inside a container that has `overflow: auto|hidden`. The `hoist` attribute forces the panel to use a fixed positioning strategy, allowing it to break out of the container. In this case, the panel will be positioned relative to its containing block, which is usually the viewport unless an ancestor uses a `transform`, `perspective`, or `filter`. [Refer to this page](https://developer.mozilla.org/en-US/docs/Web/CSS/position#fixed) for more details.
```html:preview
<div class="dropdown-hoist">
<sl-dropdown>
<sl-button slot="trigger" caret>No Hoist</sl-button>
<sl-menu>
<sl-menu-item>Item 1</sl-menu-item>
<sl-menu-item>Item 2</sl-menu-item>
<sl-menu-item>Item 3</sl-menu-item>
</sl-menu>
</sl-dropdown>
<sl-dropdown hoist>
<sl-button slot="trigger" caret>Hoist</sl-button>
<sl-menu>
<sl-menu-item>Item 1</sl-menu-item>
<sl-menu-item>Item 2</sl-menu-item>
<sl-menu-item>Item 3</sl-menu-item>
</sl-menu>
</sl-dropdown>
</div>
<style>
.dropdown-hoist {
position: relative;
border: solid 2px var(--sl-panel-border-color);
padding: var(--sl-spacing-medium);
overflow: hidden;
}
</style>
```
```jsx:react
import { SlButton, SlDivider, SlDropdown, SlIcon, SlMenu, SlMenuItem } from '@shoelace-style/shoelace/dist/react';
const css = `
.dropdown-hoist {
border: solid 2px var(--sl-panel-border-color);
padding: var(--sl-spacing-medium);
overflow: hidden;
}
`;
const App = () => (
<>
<div className="dropdown-hoist">
<SlDropdown>
<SlButton slot="trigger" caret>
No Hoist
</SlButton>
<SlMenu>
<SlMenuItem>Item 1</SlMenuItem>
<SlMenuItem>Item 2</SlMenuItem>
<SlMenuItem>Item 3</SlMenuItem>
</SlMenu>
</SlDropdown>
<SlDropdown hoist>
<SlButton slot="trigger" caret>
Hoist
</SlButton>
<SlMenu>
<SlMenuItem>Item 1</SlMenuItem>
<SlMenuItem>Item 2</SlMenuItem>
<SlMenuItem>Item 3</SlMenuItem>
</SlMenu>
</SlDropdown>
</div>
<style>{css}</style>
</>
);
```