Dropdown

<gr-dropdown> | GrDropdown

Dropdowns expose additional content that "drops down" in a panel.

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 to provide a list of options the user can select from. However, dropdowns can also be used in lower-level applications (e.g. select). The API gives you complete control over showing, hiding, and positioning the panel.

<gr-dropdown>
  <gr-button slot="trigger" caret>Dropdown</gr-button>
  <gr-menu>
    <gr-menu-item>Dropdown Item 1</gr-menu-item>
    <gr-menu-item>Dropdown Item 2</gr-menu-item>
    <gr-menu-item>Dropdown Item 3</gr-menu-item>
    <gr-menu-divider></gr-menu-divider>
    <gr-menu-item checked>Checked</gr-menu-item>
    <gr-menu-item disabled>Disabled</gr-menu-item>
    <gr-menu-divider></gr-menu-divider>
    <gr-menu-item>
      Start Icon
      <ion-icon slot="start" name="gift-outline" aria-hidden="true"></ion-icon>
    </gr-menu-item>
    <gr-menu-item>
      End Icon
      <ion-icon slot="end" name="heart-outline" aria-hidden="true"></ion-icon>
    </gr-menu-item>
  </gr-menu>
</gr-dropdown>

Options

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.

<gr-dropdown placement="top-start">
  <gr-button slot="trigger" caret>Edit</gr-button>
  <gr-menu>
    <gr-menu-item>Cut</gr-menu-item>
    <gr-menu-item>Copy</gr-menu-item>
    <gr-menu-item>Paste</gr-menu-item>
    <gr-menu-divider></gr-menu-divider>
    <gr-menu-item>Find</gr-menu-item>
    <gr-menu-item>Replace</gr-menu-item>
  </gr-menu>
</gr-dropdown>

Distance

The distance from the panel to the trigger can be customized using the distance attribute. This value is specified in pixels.

<gr-dropdown distance="30">
  <gr-button slot="trigger" caret>Edit</gr-button>
  <gr-menu>
    <gr-menu-item>Cut</gr-menu-item>
    <gr-menu-item>Copy</gr-menu-item>
    <gr-menu-item>Paste</gr-menu-item>
    <gr-menu-divider></gr-menu-divider>
    <gr-menu-item>Find</gr-menu-item>
    <gr-menu-item>Replace</gr-menu-item>
  </gr-menu>
</gr-dropdown>

Skidding

The offset of the panel along the trigger can be customized using the skidding attribute. This value is specified in pixels.

<gr-dropdown skidding="30">
  <gr-button slot="trigger" caret>Edit</gr-button>
  <gr-menu>
    <gr-menu-item>Cut</gr-menu-item>
    <gr-menu-item>Copy</gr-menu-item>
    <gr-menu-item>Paste</gr-menu-item>
    <gr-menu-divider></gr-menu-divider>
    <gr-menu-item>Find</gr-menu-item>
    <gr-menu-item>Replace</gr-menu-item>
  </gr-menu>
</gr-dropdown>

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 for more details.

<div class="dropdown-hoist">
  <gr-dropdown>
    <gr-button slot="trigger" caret>No Hoist</gr-button>
    <gr-menu>
      <gr-menu-item>Item 1</gr-menu-item>
      <gr-menu-item>Item 2</gr-menu-item>
      <gr-menu-item>Item 3</gr-menu-item>
    </gr-menu>
  </gr-dropdown>

  <gr-dropdown hoist>
    <gr-button slot="trigger" caret>Hoist</gr-button>
    <gr-menu>
      <gr-menu-item>Item 1</gr-menu-item>
      <gr-menu-item>Item 2</gr-menu-item>
      <gr-menu-item>Item 3</gr-menu-item>
    </gr-menu>
  </gr-dropdown>
</div>

<style>
  .dropdown-hoist {
    border: solid 2px var(--gr-panel-border-color);
    padding: var(--gr-spacing-medium);
    overflow: hidden;
  }
</style>

Getting the Selected Item

When dropdowns are used with menus, you can listen for the gr-select 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.

<div class="dropdown-selection">
  <gr-dropdown>
    <gr-button slot="trigger" caret>Edit</gr-button>
    <gr-menu>
      <gr-menu-item value="cut">Cut</gr-menu-item>
      <gr-menu-item value="copy">Copy</gr-menu-item>
      <gr-menu-item value="paste">Paste</gr-menu-item>
    </gr-menu>
  </gr-dropdown>
</div>

<script>
  const container = document.querySelector('.dropdown-selection');
  const dropdown = container.querySelector('gr-dropdown');

  dropdown.addEventListener('gr-select', (event) => {
    const selectedItem = event.detail.item;
    console.log(selectedItem.value);
  });
</script>

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.

<div class="dropdown-selection-alt">
  <gr-dropdown>
    <gr-button slot="trigger" caret>Edit</gr-button>
    <gr-menu>
      <gr-menu-item value="cut">Cut</gr-menu-item>
      <gr-menu-item value="copy">Copy</gr-menu-item>
      <gr-menu-item value="paste">Paste</gr-menu-item>
    </gr-menu>
  </gr-dropdown>
</div>

<script>
  const container = document.querySelector('.dropdown-selection-alt');
  const cut = container.querySelector('gr-menu-item[value="cut"]');
  const copy = container.querySelector('gr-menu-item[value="copy"]');
  const paste = container.querySelector('gr-menu-item[value="paste"]');

  cut.addEventListener('click', () => console.log('cut'));
  copy.addEventListener('click', () => console.log('copy'));
  paste.addEventListener('click', () => console.log('paste'));
</script>

Properties

Events

Methods

focusOnTrigger() => Promise<void>

Sets focus on the trigger.

Returns

Type: Promise<void>

hide() => Promise<void>

Hides the dropdown panel

Returns

Type: Promise<void>

show() => Promise<void>

Shows the dropdown panel

Returns

Type: Promise<void>

Slots

CSS custom properties

Dependencies

Used by

• gr-select