Split Panel
Examples
Initial Position
Initial Position in Pixels
Vertical
Snapping
Disabled
Setting the Primary Panel
Min & Max
Nested Split Panels
Customizing the Divider
Importing
Slots
Properties
Events
Custom Properties
Parts

Split Panel

<sl-split-panel> | SlSplitPanel

Since 2.0

stable

Split panels display two adjacent panels, allowing the user to reposition them.

Start

End

<sl-split-panel>
  <div
    slot="start"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    Start
  </div>
  <div
    slot="end"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    End
  </div>
</sl-split-panel>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

const App = () => (
  <SlSplitPanel>
    <div
      slot="start"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      Start
    </div>
    <div
      slot="end"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      End
    </div>
  </SlSplitPanel>
);

Examples

Initial Position

To set the initial position, use the position attribute. If no position is provided, it will default to 50% of the available space.

Start

End

<sl-split-panel position="75">
  <div
    slot="start"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    Start
  </div>
  <div
    slot="end"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    End
  </div>
</sl-split-panel>

Initial Position in Pixels

To set the initial position in pixels instead of a percentage, use the position-in-pixels attribute.

Start

End

<sl-split-panel position-in-pixels="150">
  <div
    slot="start"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    Start
  </div>
  <div
    slot="end"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    End
  </div>
</sl-split-panel>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

const App = () => (
  <SlSplitPanel position="200">
    <div
      slot="start"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      Start
    </div>
    <div
      slot="end"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      End
    </div>
  </SlSplitPanel>
);

Vertical

Add the vertical attribute to render the split panel in a vertical orientation where the start and end panels are stacked. You also need to set a height when using the vertical orientation.

Start

End

<sl-split-panel vertical style="height: 400px;">
  <div
    slot="start"
    style="height: 100%; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    Start
  </div>
  <div
    slot="end"
    style="height: 100%; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    End
  </div>
</sl-split-panel>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

const App = () => (
  <SlSplitPanel vertical style={{ height: '400px' }}>
    <div
      slot="start"
      style={{
        height: '100%',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      Start
    </div>
    <div
      slot="end"
      style={{
        height: '100%',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      End
    </div>
  </SlSplitPanel>
);

Snapping

To snap panels at specific positions while dragging, add the snap attribute with one or more space-separated values. Values must be in pixels or percentages. For example, to snap the panel at 100px and 50%, use snap="100px 50%". You can also customize how close the divider must be before snapping with the snap-threshold attribute.

Start

End

<div class="split-panel-snapping">
  <sl-split-panel snap="100px 50%">
    <div
      slot="start"
      style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
    >
      Start
    </div>
    <div
      slot="end"
      style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
    >
      End
    </div>
  </sl-split-panel>

  <div class="split-panel-snapping-dots"></div>
</div>

<style>
  .split-panel-snapping {
    position: relative;
  }

  .split-panel-snapping-dots::before,
  .split-panel-snapping-dots::after {
    content: '';
    position: absolute;
    bottom: -12px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--sl-color-neutral-400);
    transform: translateX(-3px);
  }

  .split-panel-snapping-dots::before {
    left: 100px;
  }

  .split-panel-snapping-dots::after {
    left: 50%;
  }
</style>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

const css = `
  .split-panel-snapping {
    position: relative;
  }

  .split-panel-snapping-dots::before,
  .split-panel-snapping-dots::after {
    content: '';
    position: absolute;
    bottom: -12px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--sl-color-neutral-400);
    transform: translateX(-3px);
  }

  .split-panel-snapping-dots::before {
    left: 100px;
  }

  .split-panel-snapping-dots::after {
    left: 50%;
  }
`;

const App = () => (
  <>
    <div className="split-panel-snapping">
      <SlSplitPanel snap="100px 50%">
        <div
          slot="start"
          style={{
            height: '200px',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          Start
        </div>
        <div
          slot="end"
          style={{
            height: '200px',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          End
        </div>
      </SlSplitPanel>

      <div className="split-panel-snapping-dots" />
    </div>

    <style>{css}</style>
  </>
);

Disabled

Add the disabled attribute to prevent the divider from being repositioned.

Start

End

<sl-split-panel disabled>
  <div
    slot="start"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    Start
  </div>
  <div
    slot="end"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    End
  </div>
</sl-split-panel>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

const App = () => (
  <SlSplitPanel disabled>
    <div
      slot="start"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      Start
    </div>
    <div
      slot="end"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      End
    </div>
  </SlSplitPanel>
);

Setting the Primary Panel

By default, both panels will grow or shrink proportionally when the host element is resized. If a primary panel is designated, it will maintain its size and the secondary panel will grow or shrink to fit the remaining space. You can set the primary panel to start or end using the primary attribute.

Try resizing the example below with each option and notice how the panels respond.

Start

End

None

Start

End

<div class="split-panel-primary">
  <sl-split-panel>
    <div
      slot="start"
      style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
    >
      Start
    </div>
    <div
      slot="end"
      style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
    >
      End
    </div>
  </sl-split-panel>

  <sl-select label="Primary Panel" value="" style="max-width: 200px; margin-top: 1rem;">
    <sl-option value="">None</sl-option>
    <sl-option value="start">Start</sl-option>
    <sl-option value="end">End</sl-option>
  </sl-select>
</div>

<script>
  const container = document.querySelector('.split-panel-primary');
  const splitPanel = container.querySelector('sl-split-panel');
  const select = container.querySelector('sl-select');

  select.addEventListener('sl-change', () => (splitPanel.primary = select.value));
</script>

import { useState } from 'react';
import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';
import SlSelect from '@shoelace-style/shoelace/dist/react/select';
import SlMenuItem from '@shoelace-style/shoelace/dist/react/menu-item';

const App = () => {
  const [primary, setPrimary] = useState('');

  return (
    <>
      <SlSplitPanel primary={primary}>
        <div
          slot="start"
          style={{
            height: '200px',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          Start
        </div>
        <div
          slot="end"
          style={{
            height: '200px',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          End
        </div>
      </SlSplitPanel>

      <SlSelect
        label="Primary Panel"
        value={primary}
        style={{ maxWidth: '200px', marginTop: '1rem' }}
        onSlChange={event => setPrimary(event.target.value)}
      >
        <SlMenuItem value="">None</SlMenuItem>
        <SlMenuItem value="start">Start</SlMenuItem>
        <SlMenuItem value="end">End</SlMenuItem>
      </SlSelect>
    </>
  );
};

Min & Max

To set a minimum or maximum size of the primary panel, use the --min and --max custom properties. Since the secondary panel is flexible, size constraints can only be applied to the primary panel. If no primary panel is designated, these constraints will be applied to the start panel.

This examples demonstrates how you can ensure both panels are at least 150px using --min, --max, and the calc() function.

Start

End

<sl-split-panel style="--min: 150px; --max: calc(100% - 150px);">
  <div
    slot="start"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    Start
  </div>
  <div
    slot="end"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    End
  </div>
</sl-split-panel>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

const App = () => (
  <SlSplitPanel style={{ '--min': '150px', '--max': 'calc(100% - 150px)' }}>
    <div
      slot="start"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      Start
    </div>
    <div
      slot="end"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      End
    </div>
  </SlSplitPanel>
);

Nested Split Panels

Create complex layouts that can be repositioned independently by nesting split panels.

Start

Top

Bottom

<sl-split-panel>
  <div
    slot="start"
    style="height: 400px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden"
  >
    Start
  </div>
  <div slot="end">
    <sl-split-panel vertical style="height: 400px;">
      <div
        slot="start"
        style="height: 100%; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden"
      >
        Top
      </div>
      <div
        slot="end"
        style="height: 100%; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden"
      >
        Bottom
      </div>
    </sl-split-panel>
  </div>
</sl-split-panel>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

const App = () => (
  <SlSplitPanel>
    <div
      slot="start"
      style={{
        height: '400px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      Start
    </div>
    <div slot="end">
      <SlSplitPanel vertical style={{ height: '400px' }}>
        <div
          slot="start"
          style={{
            height: '100%',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          Start
        </div>
        <div
          slot="end"
          style={{
            height: '100%',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          End
        </div>
      </SlSplitPanel>
    </div>
  </SlSplitPanel>
);

Customizing the Divider

You can target the divider part to apply CSS properties to the divider. To add a custom handle, slot an icon into the divider slot. When customizing the divider, make sure to think about focus styles for keyboard users.

Start

End

<sl-split-panel style="--divider-width: 20px;">
  <sl-icon slot="divider" name="grip-vertical"></sl-icon>
  <div
    slot="start"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    Start
  </div>
  <div
    slot="end"
    style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
  >
    End
  </div>
</sl-split-panel>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';
import SlIcon from '@shoelace-style/shoelace/dist/react/icon';

const App = () => (
  <SlSplitPanel style={{ '--divider-width': '20px' }}>
    <SlIcon slot="divider" name="grip-vertical" />
    <div
      slot="start"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      Start
    </div>
    <div
      slot="end"
      style={{
        height: '200px',
        background: 'var(--sl-color-neutral-50)',
        display: 'flex',
        alignItems: 'center',
        justifyContent: 'center'
      }}
    >
      End
    </div>
  </SlSplitPanel>
);

Here’s a more elaborate example that changes the divider’s color and width and adds a styled handle.

Start

End

<div class="split-panel-divider">
  <sl-split-panel>
    <sl-icon slot="divider" name="grip-vertical"></sl-icon>
    <div
      slot="start"
      style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
    >
      Start
    </div>
    <div
      slot="end"
      style="height: 200px; background: var(--sl-color-neutral-50); display: flex; align-items: center; justify-content: center; overflow: hidden;"
    >
      End
    </div>
  </sl-split-panel>
</div>

<style>
  .split-panel-divider sl-split-panel {
    --divider-width: 2px;
  }

  .split-panel-divider sl-split-panel::part(divider) {
    background-color: var(--sl-color-pink-600);
  }

  .split-panel-divider sl-icon {
    position: absolute;
    border-radius: var(--sl-border-radius-small);
    background: var(--sl-color-pink-600);
    color: var(--sl-color-neutral-0);
    padding: 0.5rem 0.125rem;
  }

  .split-panel-divider sl-split-panel::part(divider):focus-visible {
    background-color: var(--sl-color-primary-600);
  }

  .split-panel-divider sl-split-panel:focus-within sl-icon {
    background-color: var(--sl-color-primary-600);
    color: var(--sl-color-neutral-0);
  }
</style>

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';
import SlIcon from '@shoelace-style/shoelace/dist/react/icon';

const css = `
  .split-panel-divider sl-split-panel {
    --divider-width: 2px;
  }

  .split-panel-divider sl-split-panel::part(divider) {
    background-color: var(--sl-color-pink-600);
  }

  .split-panel-divider sl-icon {
    position: absolute;
    border-radius: var(--sl-border-radius-small);
    background: var(--sl-color-pink-600);
    color: var(--sl-color-neutral-0);
    padding: .5rem .125rem;
  }

  .split-panel-divider sl-split-panel::part(divider):focus-visible {
    background-color: var(--sl-color-primary-600);
  }

  .split-panel-divider sl-split-panel:focus-within sl-icon {
    background-color: var(--sl-color-primary-600);
    color: var(--sl-color-neutral-0);
  }
`;

const App = () => (
  <>
    <div className="split-panel-divider">
      <SlSplitPanel>
        <SlIcon slot="divider" name="grip-vertical" />
        <div
          slot="start"
          style={{
            height: '200px',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          Start
        </div>
        <div
          slot="end"
          style={{
            height: '200px',
            background: 'var(--sl-color-neutral-50)',
            display: 'flex',
            alignItems: 'center',
            justifyContent: 'center'
          }}
        >
          End
        </div>
      </SlSplitPanel>
    </div>

    <style>{css}</style>
  </>
);

Importing

If you’re using the autoloader or the traditional loader, you can ignore this section. Otherwise, feel free to use any of the following snippets to cherry pick this component.

Script

Import

Bundler

React

To import this component from the CDN using a script tag:

<script type="module" src="https://cdn.jsdelivr.net/npm/@shoelace-style/shoelace@2.18.0/cdn/components/split-panel/split-panel.js"></script>

To import this component from the CDN using a JavaScript import:

import 'https://cdn.jsdelivr.net/npm/@shoelace-style/shoelace@2.18.0/cdn/components/split-panel/split-panel.js';

To import this component using a bundler:

import '@shoelace-style/shoelace/dist/components/split-panel/split-panel.js';

To import this component as a React component:

import SlSplitPanel from '@shoelace-style/shoelace/dist/react/split-panel';

Slots

Name	Description
`start`	Content to place in the start panel.
`end`	Content to place in the end panel.
`divider`	The divider. Useful for slotting in a custom icon that renders as a handle.

Learn more about using slots.

Properties

Name	Description	Type	Default
`position`	The current position of the divider from the primary panel’s edge as a percentage 0–100. Defaults to 50% of the container’s initial size.	`number`	`50`
`positionInPixels` `position-in-pixels`	The current position of the divider from the primary panel’s edge in pixels.	`number`	-
`vertical`	Draws the split panel in a vertical orientation with the start and end panels stacked.	`boolean`	`false`
`disabled`	Disables resizing. Note that the position may still change as a result of resizing the host element.	`boolean`	`false`
`primary`	If no primary panel is designated, both panels will resize proportionally when the host element is resized. If a primary panel is designated, it will maintain its size and the other panel will grow or shrink as needed when the host element is resized.	`'start' \| 'end' \| undefined`	-
`snap`	One or more space-separated values at which the divider should snap. Values can be in pixels or percentages, e.g. `"100px 50%"`.	`string \| undefined`	-
`snapThreshold` `snap-threshold`	How close the divider must be to a snap point until snapping occurs.	`number`	`12`
`updateComplete`	A read-only promise that resolves when the component has finished updating.

Learn more about attributes and properties.

Events

Name	React Event	Description	Event Detail
`sl-reposition`	`onSlReposition`	Emitted when the divider’s position changes.	-

Learn more about events.

Custom Properties

Name	Description	Default
`--divider-width`	The width of the visible divider.	4px
`--divider-hit-area`	The invisible region around the divider where dragging can occur. This is usually wider than the divider to facilitate easier dragging.	12px
`--min`	The minimum allowed size of the primary panel.	0
`--max`	The maximum allowed size of the primary panel.	100%

Learn more about customizing CSS custom properties.

Parts

Name	Description
`start`	The start panel.
`end`	The end panel.
`panel`	Targets both the start and end panels.
`divider`	The divider that separates the start and end panels.

Learn more about customizing CSS parts.