Arrow keys handling

src/widget/widget.js

@@ -89,13 +89,25 @@ export default class Widget extends Plugin {
 	 */
 	_onKeydown( eventInfo, domEventData  ) {
 		const keyCode = domEventData.keyCode;
+		const isForward = keyCode == keyCodes.delete || keyCode == keyCodes.arrowdown || keyCode == keyCodes.arrowright;
 
-		// Handle only delete and backspace.
-		if ( keyCode !== keyCodes.delete && keyCode !== keyCodes.backspace ) {
-			return;
+		// Checks if delete/backspace or arrow keys were handled and then prevents default event behaviour and stops
+		// event propagation.
+		if ( ( isDeleteKeyCode( keyCode ) && this._handleDelete( isForward ) ) ||
+			( isArrowKeyCode( keyCode ) && this._handleArrowKeys( isForward ) ) ) {
+			domEventData.preventDefault();
+			eventInfo.stop();
 		}
+	}
 
-		const dataController = this.editor.data;
+	/**
+	 * Handles delete keys: backspace and delete.
+	 *
+	 * @private
+	 * @param {Boolean} isForward Set to true if delete was performed in forward direction.
+	 * @returns {Boolean|undefined} Returns `true` if keys were handled correctly.
+	 */
+	_handleDelete( isForward ) {
 		const modelDocument = this.editor.document;
 		const modelSelection = modelDocument.selection;
 
@@ -104,22 +116,12 @@ export default class Widget extends Plugin {
 			return;
 		}
 
-		// Clone current selection to use it as a probe. We must leave default selection as it is so it can return
-		// to its current state after undo.
-		const probe = ModelSelection.createFromSelection( modelSelection );
-		const isForward = ( keyCode == keyCodes.delete );
-
-		dataController.modifySelection( probe, { direction: isForward ? 'forward' : 'backward' } );
-
-		const objectElement = isForward ? probe.focus.nodeBefore : probe.focus.nodeAfter;
-
-		if ( objectElement instanceof ModelElement && modelDocument.schema.objects.has( objectElement.name ) ) {
-			domEventData.preventDefault();
-			eventInfo.stop();
+		const objectElement = this._getObjectElementNextToSelection( isForward );
 
+		if ( objectElement ) {
 			modelDocument.enqueueChanges( () => {
 				// Remove previous element if empty.
-				const previousNode = probe.anchor.parent;
+				const previousNode = modelSelection.anchor.parent;
 
 				if ( previousNode.isEmpty ) {
 					const batch = modelDocument.batch();
@@ -128,6 +130,51 @@ export default class Widget extends Plugin {
 
 				this._setSelectionOverElement( objectElement );
 			} );
+
+			return true;
+		}
+	}
+
+	/**
+	 * Handles arrow keys.
+	 *
+	 * @param {Boolean} isForward Set to true if arrow key should be handled in forward direction.
+	 * @returns {Boolean|undefined} Returns `true` if keys were handled correctly.
+	 */
+	_handleArrowKeys( isForward ) {
+		const modelDocument = this.editor.document;
+		const schema = modelDocument.schema;
+		const modelSelection = modelDocument.selection;
+		const objectElement = getSelectedElement( modelSelection );
+
+		// if object element is selected.
+		if ( objectElement && schema.objects.has( objectElement.name ) ) {
+			const position = isForward ? modelSelection.getLastPosition() : modelSelection.getFirstPosition();
+			const newRange = modelDocument.getNearestSelectionRange( position, isForward ? 'forward' : 'backward' );
+
+			if ( newRange ) {
+				modelDocument.enqueueChanges( () => {
+					modelSelection.setRanges( [ newRange ] );
+				} );
+			}
+
+			return true;
+		}
+
+		// If selection is next to object element.
+		// Return if not collapsed.
+		if ( !modelSelection.isCollapsed ) {
+			return;
+		}
+
+		const objectElement2 = this._getObjectElementNextToSelection( isForward );
+
+		if ( objectElement2 instanceof ModelElement && modelDocument.schema.objects.has( objectElement2.name ) ) {
+			modelDocument.enqueueChanges( () => {
+				this._setSelectionOverElement( objectElement2 );
+			} );
+
+			return true;
 		}
 	}
 
@@ -140,4 +187,69 @@ export default class Widget extends Plugin {
 	_setSelectionOverElement( element ) {
 		this.editor.document.selection.setRanges( [ ModelRange.createOn( element ) ] );
 	}
+
+	/**
+	 * Checks if {@link module:engine/model/element~Element element} placed next to the current
+	 * {@link module:engine/model/selection~Selection model selection} exists and is marked in
+	 * {@link module:engine/model/schema~Schema schema} as `object`.
+	 *
+	 * @private
+	 * @param {Boolean} forward Direction of checking.
+	 * @returns {module:engine/model/element~Element|null}
+	 */
+	_getObjectElementNextToSelection( forward ) {
+		const modelDocument = this.editor.document;
+		const schema = modelDocument.schema;
+		const modelSelection = modelDocument.selection;
+		const dataController = this.editor.data;
+
+		// Clone current selection to use it as a probe. We must leave default selection as it is so it can return
+		// to its current state after undo.
+		const probe = ModelSelection.createFromSelection( modelSelection );
+		dataController.modifySelection( probe, { direction: forward ? 'forward' : 'backward' } );
+		const objectElement = forward ? probe.focus.nodeBefore : probe.focus.nodeAfter;
+
+		if ( objectElement instanceof ModelElement && schema.objects.has( objectElement.name ) ) {
+			return objectElement;
+		}
+
+		return null;
+	}
+}
+
+// Returns the selected element. {@link module:engine/model/element~Element Element} is considered as selected if there is only
+// one range in the selection, and that range contains exactly one element.
+// Returns `null` if there is no selected element.
+//
+// @param {module:engine/model/selection~Selection} modelSelection
+// @returns {module:engine/model/element~Element|null}
+function getSelectedElement( modelSelection ) {
+	if ( modelSelection.rangeCount !== 1 ) {
+		return null;
+	}
+
+	const range = modelSelection.getFirstRange();
+	const nodeAfterStart = range.start.nodeAfter;
+	const nodeBeforeEnd = range.end.nodeBefore;
+
+	return ( nodeAfterStart instanceof ModelElement && nodeAfterStart == nodeBeforeEnd ) ? nodeAfterStart : null;
+}
+
+// Returns 'true' if provided key code represents one of the arrow keys.
+//
+// @param {Number} keyCode
+// @returns {Boolean}
+function isArrowKeyCode( keyCode ) {
+	return keyCode == keyCodes.arrowright ||
+		keyCode == keyCodes.arrowleft ||
+		keyCode == keyCodes.arrowup ||
+		keyCode == keyCodes.arrowdown;
+}
+
+//Returns 'true' if provided key code represents one of the delete keys: delete or backspace.
+//
+//@param {Number} keyCode
+//@returns {Boolean}
+function isDeleteKeyCode( keyCode ) {
+	return keyCode == keyCodes.delete || keyCode == keyCodes.backspace;
 }

tests/manual/image.html

@@ -3,6 +3,12 @@
 </head>
 
 <div id="editor">
+	<figure class="image">
+		<img src="logo.png" alt="" />
+	</figure>
+	<figure class="image">
+		<img src="logo.png" alt="" />
+	</figure>
 	<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nulla finibus consequat placerat. Vestibulum id tellus et mauris sagittis tincidunt quis id mauris. Curabitur consectetur lectus sit amet tellus mattis, non lobortis leo interdum. </p>
 	<figure class="image">
 		<img src="logo.png" alt="CKEditor logo" />
@@ -11,4 +17,7 @@
 	<figure class="image">
 		<img src="logo.png" alt="" />
 	</figure>
+	<figure class="image">
+		<img src="logo.png" alt="" />
+	</figure>
 </div>

tests/manual/image.md

@@ -12,3 +12,10 @@
 * Place selection at the beginning of the second paragraph and press <kbd>backspace</kbd> (<kbd>delete</kbd> on Mac) - image should be selected. Second press should delete it.
 * Place selection in an empty paragraph before image and press <kbd>delete</kbd> (<kbd>forward delete</kbd> on Mac) - image should be selected and paragraph removed.
 * Place selection in an empty paragraph after image and press <kbd>backspace</kbd> (<kbd>delete</kbd> on Mac) - image should be selected and paragraph removed.
+
+### Arrow key handling
+
+* Click first image and press <kbd>right arrow</kbd> - second image should be selected. Same effect should happen for <kbd>down arrow</kbd>.
+* Click second image and press <kbd>left arrow</kbd> - first image should be selected. Same effect should happen for <kbd>up arrow</kbd>.
+* Place selection at the end of the first paragraph and press <kbd>right arrow</kbd> - third image should be selected. Same effect should happen for <kbd>down arrow</kbd>.
+* Place selection at the beginning of the first paragraph and press <kbd>left arrow</kbd> - first image should be selected. Same effect should happen for <kbd>up arrow</kbd>.