Fix missing Add Template Part button in Template Parts page

packages/edit-site/src/components/page-template-parts/add-new-template-part.js

@@ -0,0 +1,57 @@
+/**
+ * WordPress dependencies
+ */
+import { privateApis as routerPrivateApis } from '@wordpress/router';
+import { useSelect } from '@wordpress/data';
+import { store as coreStore } from '@wordpress/core-data';
+import { useState } from '@wordpress/element';
+import { Button } from '@wordpress/components';
+
+/**
+ * Internal dependencies
+ */
+import { unlock } from '../../lock-unlock';
+import { store as editSiteStore } from '../../store';
+import CreateTemplatePartModal from '../create-template-part-modal';
+
+const { useHistory } = unlock( routerPrivateApis );
+
+export default function AddNewTemplatePart() {
+	const { canCreate, postType } = useSelect( ( select ) => {
+		const { supportsTemplatePartsMode } =
+			select( editSiteStore ).getSettings();
+		return {
+			canCreate: ! supportsTemplatePartsMode,
+			postType: select( coreStore ).getPostType( 'wp_template_part' ),
+		};
+	}, [] );
+	const [ isModalOpen, setIsModalOpen ] = useState( false );
+	const history = useHistory();
+
+	if ( ! canCreate || ! postType ) {
+		return null;
+	}
+
+	return (
+		<>
+			<Button variant="primary" onClick={ () => setIsModalOpen( true ) }>
+				{ postType.labels.add_new_item }
+			</Button>
+			{ isModalOpen && (
+				<CreateTemplatePartModal
+					closeModal={ () => setIsModalOpen( false ) }
+					blocks={ [] }
+					onCreate={ ( templatePart ) => {
+						setIsModalOpen( false );
+						history.push( {
+							postId: templatePart.id,
+							postType: 'wp_template_part',
+							canvas: 'edit',
+						} );
+					} }
+					onError={ () => setIsModalOpen( false ) }
+				/>
+			) }
+		</>
+	);
+}

packages/edit-site/src/components/page-template-parts/index.js

@@ -7,8 +7,7 @@ import {
 	__experimentalVStack as VStack,
 } from '@wordpress/components';
 import { __ } from '@wordpress/i18n';
-import { useSelect } from '@wordpress/data';
-import { store as coreStore, useEntityRecords } from '@wordpress/core-data';
+import { useEntityRecords } from '@wordpress/core-data';
 import { decodeEntities } from '@wordpress/html-entities';
 
 /**
@@ -19,8 +18,7 @@ import Table from '../table';
 import Link from '../routes/link';
 import AddedBy from '../list/added-by';
 import TemplateActions from '../template-actions';
-import AddNewTemplate from '../add-new-template';
-import { store as editSiteStore } from '../../store';
+import AddNewTemplatePart from './add-new-template-part';
 
 export default function PageTemplateParts() {
 	const { records: templateParts } = useEntityRecords(
@@ -31,15 +29,6 @@ export default function PageTemplateParts() {
 		}
 	);
 
-	const { canCreate } = useSelect( ( select ) => {
-		const { supportsTemplatePartsMode } =
-			select( editSiteStore ).getSettings();
-		return {
-			postType: select( coreStore ).getPostType( 'wp_template_part' ),
-			canCreate: ! supportsTemplatePartsMode,
-		};
-	} );
-
 	const columns = [
 		{
 			header: __( 'Template Part' ),
@@ -87,15 +76,7 @@ export default function PageTemplateParts() {
 	return (
 		<Page
 			title={ __( 'Template Parts' ) }
-			actions={
-				canCreate && (
-					<AddNewTemplate
-						templateType={ 'wp_template_part' }
-						showIcon={ false }
-						toggleProps={ { variant: 'primary' } }
-					/>
-				)
-			}
+			actions={ <AddNewTemplatePart /> }
 		>
 			{ templateParts && (
 				<Table data={ templateParts } columns={ columns } />