Draggable: Allow elementId based elements to be attached to the ownerDocument body

packages/components/CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Enhancements
 
+-   `Draggable`: Add `appendToOwnerDocument` prop to allow elementId based elements to be attached to the ownerDocument body ([#49911](https://github.com/WordPress/gutenberg/pull/49911)).
 -   `TreeGrid`: Modify keyboard navigation code to use a data-expanded attribute if aria-expanded is to be controlled outside of the TreeGrid component ([#48461](https://github.com/WordPress/gutenberg/pull/48461)).
 -   `Modal`: Equalize internal spacing ([#49890](https://github.com/WordPress/gutenberg/pull/49890)).
 -   `Modal`: Increased border radius ([#49870](https://github.com/WordPress/gutenberg/pull/49870)).

packages/components/src/draggable/README.md

@@ -8,9 +8,16 @@ Note that the drag handle needs to declare the `draggable="true"` property and b
 
 The component accepts the following props:
 
+### `appendToOwnerDocument`: `boolean`
+
+Whether to append the cloned element to the `ownerDocument` body. By default, elements sourced by id are appended to the element's wrapper.
+
+-   Required: No
+-   Default: `false`
+
 ### `elementId`: `string`
 
-The HTML id of the element to clone on drag
+The HTML id of the element to clone on drag.
 
 -   Required: Yes
 

packages/components/src/draggable/index.tsx

@@ -63,6 +63,7 @@ export function Draggable( {
 	onDragStart,
 	onDragOver,
 	onDragEnd,
+	appendToOwnerDocument = false,
 	cloneClassname,
 	elementId,
 	transferData,
@@ -173,7 +174,11 @@ export function Draggable( {
 			cloneWrapper.appendChild( clone );
 
 			// Inject the cloneWrapper into the DOM.
-			elementWrapper?.appendChild( cloneWrapper );
+			if ( appendToOwnerDocument ) {
+				ownerDocument.body.appendChild( cloneWrapper );
+			} else {
+				elementWrapper?.appendChild( cloneWrapper );
+			}
 		}
 
 		// Mark the current cursor coordinates.

packages/components/src/draggable/stories/index.tsx

@@ -7,6 +7,7 @@ import type { DragEvent } from 'react';
 /**
  * WordPress dependencies
  */
+import { useInstanceId } from '@wordpress/compose';
 import { useState } from '@wordpress/element';
 import { Icon, more } from '@wordpress/icons';
 
@@ -32,46 +33,68 @@ export default meta;
 
 const DefaultTemplate: ComponentStory< typeof Draggable > = ( args ) => {
 	const [ isDragging, setDragging ] = useState( false );
+	const instanceId = useInstanceId( DefaultTemplate );
 
 	// Allow for the use of ID in the example.
 	return (
 		<div>
-			<p>Is Dragging? { isDragging ? 'Yes' : 'No!' }</p>
+			<p
+				style={ {
+					padding: '1em',
+					position: 'relative',
+					zIndex: 1000,
+					backgroundColor: 'whitesmoke',
+				} }
+			>
+				Is Dragging? { isDragging ? 'Yes' : 'No!' }
+			</p>
 			<div
-				/* eslint-disable no-restricted-syntax, eslint-comments/disable-enable-pair */
-				id="draggable-example-box"
-				style={ { display: 'inline-flex' } }
+				style={ {
+					zIndex: 100,
+					position: 'relative',
+				} }
 			>
-				<Draggable { ...args } elementId="draggable-example-box">
-					{ ( { onDraggableStart, onDraggableEnd } ) => {
-						const handleOnDragStart = ( event: DragEvent ) => {
-							setDragging( true );
-							onDraggableStart( event );
-						};
-						const handleOnDragEnd = ( event: DragEvent ) => {
-							setDragging( false );
-							onDraggableEnd( event );
-						};
-
-						return (
-							<div
-								onDragStart={ handleOnDragStart }
-								onDragEnd={ handleOnDragEnd }
-								draggable
-								style={ {
-									alignItems: 'center',
-									display: 'flex',
-									justifyContent: 'center',
-									width: 100,
-									height: 100,
-									background: '#ddd',
-								} }
-							>
-								<Icon icon={ more } />
-							</div>
-						);
+				<div
+					id={ `draggable-example-box-${ instanceId }` }
+					style={ {
+						display: 'inline-flex',
+						position: 'relative',
 					} }
-				</Draggable>
+				>
+					<Draggable
+						{ ...args }
+						elementId={ `draggable-example-box-${ instanceId }` }
+					>
+						{ ( { onDraggableStart, onDraggableEnd } ) => {
+							const handleOnDragStart = ( event: DragEvent ) => {
+								setDragging( true );
+								onDraggableStart( event );
+							};
+							const handleOnDragEnd = ( event: DragEvent ) => {
+								setDragging( false );
+								onDraggableEnd( event );
+							};
+
+							return (
+								<div
+									onDragStart={ handleOnDragStart }
+									onDragEnd={ handleOnDragEnd }
+									draggable
+									style={ {
+										alignItems: 'center',
+										display: 'flex',
+										justifyContent: 'center',
+										width: 100,
+										height: 100,
+										background: '#ddd',
+									} }
+								>
+									<Icon icon={ more } />
+								</div>
+							);
+						} }
+					</Draggable>
+				</div>
 			</div>
 		</div>
 	);
@@ -81,3 +104,16 @@ export const Default: ComponentStory< typeof Draggable > = DefaultTemplate.bind(
 	{}
 );
 Default.args = {};
+
+/**
+ * `appendToOwnerDocument` is used to append the element being dragged to the body of the owner document.
+ *
+ * This is useful when the element being dragged should not receive styles from its parent.
+ * For example, when the element's parent sets a `z-index` value that would cause the dragged
+ * element to be rendered behind other elements.
+ */
+export const AppendElementToOwnerDocument: ComponentStory< typeof Draggable > =
+	DefaultTemplate.bind( {} );
+AppendElementToOwnerDocument.args = {
+	appendToOwnerDocument: true,
+};

packages/components/src/draggable/types.ts

@@ -17,6 +17,13 @@ export type DraggableProps = {
 		 */
 		onDraggableEnd: ( event: DragEvent ) => void;
 	} ) => JSX.Element | null;
+	/**
+	 * Whether to append the cloned element to the `ownerDocument` body.
+	 * By default, elements sourced by id are appended to the element's wrapper.
+	 *
+	 *@default false
+	 */
+	appendToOwnerDocument?: boolean;
 	/**
 	 * Classname for the cloned element.
 	 */