Merge pull request #25 from ckeditor/t/ckeditor5/479

Feature: Enabled the decoupled editor placeholder (see ckeditor/ckeditor5#479).

BREAKING CHANGE: The second argument of `DecoupledEditorUIView.constructor()` is an editing view instance now.

Author: Piotr Jasiun

src/decouplededitor.js

@@ -73,7 +73,8 @@ export default class DecoupledEditor extends Editor {
 
 		this.model.document.createRoot();
 
-		this.ui = new DecoupledEditorUI( this, new DecoupledEditorUIView( this.locale, this.sourceElement ) );
+		const view = new DecoupledEditorUIView( this.locale, this.editing.view, this.sourceElement );
+		this.ui = new DecoupledEditorUI( this, view );
 	}
 
 	/**

src/decouplededitorui.js

@@ -10,6 +10,7 @@
 import EditorUI from '@ckeditor/ckeditor5-core/src/editor/editorui';
 import enableToolbarKeyboardFocus from '@ckeditor/ckeditor5-ui/src/toolbar/enabletoolbarkeyboardfocus';
 import normalizeToolbarConfig from '@ckeditor/ckeditor5-ui/src/toolbar/normalizetoolbarconfig';
+import { enablePlaceholder } from '@ckeditor/ckeditor5-engine/src/view/placeholder';
 
 /**
  * The decoupled editor UI class.
@@ -49,38 +50,100 @@ export default class DecoupledEditorUI extends EditorUI {
 	init() {
 		const editor = this.editor;
 		const view = this.view;
+		const editingView = editor.editing.view;
+		const editable = view.editable;
+		const editingRoot = editingView.document.getRoot();
+
+		// The editable UI and editing root should share the same name. Then name is used
+		// to recognize the particular editable, for instance in ARIA attributes.
+		view.editable.name = editingRoot.rootName;
 
 		view.render();
 
-		// Set up the editable.
-		const editingRoot = editor.editing.view.document.getRoot();
-		view.editable.bind( 'isReadOnly' ).to( editingRoot );
-		view.editable.bind( 'isFocused' ).to( editor.editing.view.document );
-		editor.editing.view.attachDomRoot( view.editable.element );
-		view.editable.name = editingRoot.rootName;
+		// The editable UI element in DOM is available for sure only after the editor UI view has been rendered.
+		// But it can be available earlier if a DOM element has been passed to DecoupledEditor.create().
+		const editableElement = editable.element;
 
-		this._editableElements.set( view.editable.name, view.editable.element );
+		// Register the editable UI view in the editor. A single editor instance can aggregate multiple
+		// editable areas (roots) but the decoupled editor has only one.
+		this._editableElements.set( editable.name, editableElement );
 
-		this.focusTracker.add( view.editable.element );
+		// Let the global focus tracker know that the editable UI element is focusable and
+		// belongs to the editor. From now on, the focus tracker will sustain the editor focus
+		// as long as the editable is focused (e.g. the user is typing).
+		this.focusTracker.add( editableElement );
 
-		this.view.toolbar.fillFromConfig( this._toolbarConfig.items, this.componentFactory );
+		// Let the editable UI element respond to the changes in the global editor focus
+		// tracker. It has been added to the same tracker a few lines above but, in reality, there are
+		// many focusable areas in the editor, like balloons, toolbars or dropdowns and as long
+		// as they have focus, the editable should act like it is focused too (although technically
+		// it isn't), e.g. by setting the proper CSS class, visually announcing focus to the user.
+		// Doing otherwise will result in editable focus styles disappearing, once e.g. the
+		// toolbar gets focused.
+		view.editable.bind( 'isFocused' ).to( this.focusTracker );
 
-		enableToolbarKeyboardFocus( {
-			origin: editor.editing.view,
-			originFocusTracker: this.focusTracker,
-			originKeystrokeHandler: editor.keystrokes,
-			toolbar: this.view.toolbar
-		} );
+		// Bind the editable UI element to the editing view, making it an end– and entry–point
+		// of the editor's engine. This is where the engine meets the UI.
+		editingView.attachDomRoot( editableElement );
 
+		this._initPlaceholder();
+		this._initToolbar();
 		this.fire( 'ready' );
 	}
 
 	/**
 	 * @inheritDoc
 	 */
 	destroy() {
-		this.view.destroy();
+		const view = this.view;
+		const editingView = this.editor.editing.view;
+
+		editingView.detachDomRoot( view.editable.name );
+		view.destroy();
 
 		super.destroy();
 	}
+
+	/**
+	 * Initializes the inline editor toolbar and its panel.
+	 *
+	 * @private
+	 */
+	_initToolbar() {
+		const editor = this.editor;
+		const view = this.view;
+		const toolbar = view.toolbar;
+
+		toolbar.fillFromConfig( this._toolbarConfig.items, this.componentFactory );
+
+		enableToolbarKeyboardFocus( {
+			origin: editor.editing.view,
+			originFocusTracker: this.focusTracker,
+			originKeystrokeHandler: editor.keystrokes,
+			toolbar
+		} );
+	}
+
+	/**
+	 * Enable the placeholder text on the editing root, if any was configured.
+	 *
+	 * @private
+	 */
+	_initPlaceholder() {
+		const editor = this.editor;
+		const editingView = editor.editing.view;
+		const editingRoot = editingView.document.getRoot();
+
+		const placeholderText = editor.config.get( 'placeholder' ) ||
+			editor.sourceElement && editor.sourceElement.getAttribute( 'placeholder' );
+
+		if ( placeholderText ) {
+			enablePlaceholder( {
+				view: editingView,
+				element: editingRoot,
+				text: placeholderText,
+				isDirectHost: false
+			} );
+		}
+	}
 }

src/decouplededitoruiview.js

@@ -28,10 +28,11 @@ export default class DecoupledEditorUIView extends EditorUIView {
 	 * Creates an instance of the decoupled editor UI view.
 	 *
 	 * @param {module:utils/locale~Locale} locale The {@link module:core/editor/editor~Editor#locale} instance.
+	 * @param {module:engine/view/view~View} editingView The editing view instance this view is related to.
 	 * @param {HTMLElement} [editableElement] The editable element. If not specified, it will be automatically created by
 	 * {@link module:ui/editableui/editableuiview~EditableUIView}. Otherwise, the given element will be used.
 	 */
-	constructor( locale, editableElement ) {
+	constructor( locale, editingView, editableElement ) {
 		super( locale );
 
 		/**
@@ -48,7 +49,7 @@ export default class DecoupledEditorUIView extends EditorUIView {
 		 * @readonly
 		 * @member {module:ui/editableui/inline/inlineeditableuiview~InlineEditableUIView}
 		 */
-		this.editable = new InlineEditableUIView( locale, editableElement );
+		this.editable = new InlineEditableUIView( locale, editingView, editableElement );
 
 		// This toolbar may be placed anywhere in the page so things like font size need to be reset in it.
 		// Also because of the above, make sure the toolbar supports rounded corners.

tests/decouplededitorui.js

@@ -10,11 +10,13 @@ import View from '@ckeditor/ckeditor5-ui/src/view';
 import VirtualTestEditor from '@ckeditor/ckeditor5-core/tests/_utils/virtualtesteditor';
 import DecoupledEditorUI from '../src/decouplededitorui';
 import EditorUI from '@ckeditor/ckeditor5-core/src/editor/editorui';
+import Paragraph from '@ckeditor/ckeditor5-paragraph/src/paragraph';
 import DecoupledEditorUIView from '../src/decouplededitoruiview';
 
 import { keyCodes } from '@ckeditor/ckeditor5-utils/src/keyboard';
 import testUtils from '@ckeditor/ckeditor5-core/tests/_utils/utils';
 import utils from '@ckeditor/ckeditor5-utils/tests/_utils/utils';
+import { isElement } from 'lodash-es';
 
 describe( 'DecoupledEditorUI', () => {
 	let editor, view, ui, viewElement;
@@ -23,7 +25,7 @@ describe( 'DecoupledEditorUI', () => {
 
 	beforeEach( () => {
 		return VirtualDecoupledTestEditor
-			.create( {
+			.create( '', {
 				toolbar: [ 'foo', 'bar' ],
 			} )
 			.then( newEditor => {
@@ -69,34 +71,75 @@ describe( 'DecoupledEditorUI', () => {
 					view.editable,
 					{ isFocused: false },
 					[
-						[ editor.editing.view.document, { isFocused: true } ]
+						[ ui.focusTracker, { isFocused: true } ]
 					],
 					{ isFocused: true }
 				);
 			} );
 
-			it( 'binds view.editable#isReadOnly', () => {
-				const editable = editor.editing.view.document.getRoot();
+			it( 'attaches editable UI as view\'s DOM root', () => {
+				expect( editor.editing.view.getDomRoot() ).to.equal( view.editable.element );
+			} );
+		} );
 
-				utils.assertBinding(
-					view.editable,
-					{ isReadOnly: false },
-					[
-						[ editable, { isReadOnly: true } ]
-					],
-					{ isReadOnly: true }
-				);
+		describe( 'placeholder', () => {
+			it( 'sets placeholder from editor.config.placeholder', () => {
+				return VirtualDecoupledTestEditor
+					.create( 'foo', {
+						extraPlugins: [ Paragraph ],
+						placeholder: 'placeholder-text',
+					} )
+					.then( newEditor => {
+						const firstChild = newEditor.editing.view.document.getRoot().getChild( 0 );
+
+						expect( firstChild.getAttribute( 'data-placeholder' ) ).to.equal( 'placeholder-text' );
+
+						return newEditor.destroy();
+					} );
 			} );
 
-			it( 'attaches editable UI as view\'s DOM root', () => {
-				expect( editor.editing.view.getDomRoot() ).to.equal( view.editable.element );
+			it( 'sets placeholder from "placeholder" attribute of a passed element', () => {
+				const element = document.createElement( 'div' );
+
+				element.setAttribute( 'placeholder', 'placeholder-text' );
+
+				return VirtualDecoupledTestEditor
+					.create( element, {
+						extraPlugins: [ Paragraph ]
+					} )
+					.then( newEditor => {
+						const firstChild = newEditor.editing.view.document.getRoot().getChild( 0 );
+
+						expect( firstChild.getAttribute( 'data-placeholder' ) ).to.equal( 'placeholder-text' );
+
+						return newEditor.destroy();
+					} );
+			} );
+
+			it( 'uses editor.config.placeholder rather than "placeholder" attribute of a passed element', () => {
+				const element = document.createElement( 'div' );
+
+				element.setAttribute( 'placeholder', 'placeholder-text' );
+
+				return VirtualDecoupledTestEditor
+					.create( element, {
+						placeholder: 'config takes precedence',
+						extraPlugins: [ Paragraph ]
+					} )
+					.then( newEditor => {
+						const firstChild = newEditor.editing.view.document.getRoot().getChild( 0 );
+
+						expect( firstChild.getAttribute( 'data-placeholder' ) ).to.equal( 'config takes precedence' );
+
+						return newEditor.destroy();
+					} );
 			} );
 		} );
 
 		describe( 'view.toolbar#items', () => {
 			it( 'are filled with the config.toolbar (specified as an Array)', () => {
 				return VirtualDecoupledTestEditor
-					.create( {
+					.create( '', {
 						toolbar: [ 'foo', 'bar' ]
 					} )
 					.then( editor => {
@@ -111,7 +154,7 @@ describe( 'DecoupledEditorUI', () => {
 
 			it( 'are filled with the config.toolbar (specified as an Object)', () => {
 				return VirtualDecoupledTestEditor
-					.create( {
+					.create( '', {
 						toolbar: {
 							items: [ 'foo', 'bar' ],
 							viewportTopOffset: 100
@@ -129,7 +172,7 @@ describe( 'DecoupledEditorUI', () => {
 		} );
 
 		it( 'initializes keyboard navigation between view#toolbar and view#editable', () => {
-			return VirtualDecoupledTestEditor.create()
+			return VirtualDecoupledTestEditor.create( '' )
 				.then( editor => {
 					const ui = editor.ui;
 					const view = ui.view;
@@ -152,6 +195,47 @@ describe( 'DecoupledEditorUI', () => {
 		} );
 	} );
 
+	describe( 'destroy()', () => {
+		it( 'detaches the DOM root then destroys the UI view', () => {
+			return VirtualDecoupledTestEditor.create( '' )
+				.then( newEditor => {
+					const destroySpy = sinon.spy( newEditor.ui.view, 'destroy' );
+					const detachSpy = sinon.spy( newEditor.editing.view, 'detachDomRoot' );
+
+					return newEditor.destroy()
+						.then( () => {
+							sinon.assert.callOrder( detachSpy, destroySpy );
+						} );
+				} );
+		} );
+
+		it( 'restores the editor element back to its original state', () => {
+			const domElement = document.createElement( 'div' );
+
+			domElement.setAttribute( 'foo', 'bar' );
+			domElement.setAttribute( 'data-baz', 'qux' );
+			domElement.classList.add( 'foo-class' );
+
+			return VirtualDecoupledTestEditor.create( domElement )
+				.then( newEditor => {
+					return newEditor.destroy()
+						.then( () => {
+							const attributes = {};
+
+							for ( const attribute of domElement.attributes ) {
+								attributes[ attribute.name ] = attribute.value;
+							}
+
+							expect( attributes ).to.deep.equal( {
+								foo: 'bar',
+								'data-baz': 'qux',
+								class: 'foo-class'
+							} );
+						} );
+				} );
+		} );
+	} );
+
 	describe( 'element()', () => {
 		it( 'returns correct element instance', () => {
 			expect( ui.element ).to.equal( viewElement );
@@ -185,10 +269,14 @@ function viewCreator( name ) {
 }
 
 class VirtualDecoupledTestEditor extends VirtualTestEditor {
-	constructor( config ) {
+	constructor( sourceElementOrData, config ) {
 		super( config );
 
-		const view = new DecoupledEditorUIView( this.locale );
+		if ( isElement( sourceElementOrData ) ) {
+			this.sourceElement = sourceElementOrData;
+		}
+
+		const view = new DecoupledEditorUIView( this.locale, this.editing.view );
 		this.ui = new DecoupledEditorUI( this, view );
 
 		this.ui.componentFactory.add( 'foo', viewCreator( 'foo' ) );
@@ -201,14 +289,20 @@ class VirtualDecoupledTestEditor extends VirtualTestEditor {
 		return super.destroy();
 	}
 
-	static create( config ) {
+	static create( sourceElementOrData, config ) {
 		return new Promise( resolve => {
-			const editor = new this( config );
+			const editor = new this( sourceElementOrData, config );
 
 			resolve(
 				editor.initPlugins()
 					.then( () => {
 						editor.ui.init();
+
+						const initialData = isElement( sourceElementOrData ) ?
+							sourceElementOrData.innerHTML :
+							sourceElementOrData;
+
+						editor.data.init( initialData );
 						editor.fire( 'ready' );
 					} )
 					.then( () => editor )