From 88fae11ff42fed5cdaf796f34a84625740da8494 Mon Sep 17 00:00:00 2001
From: Anna Gavrilman <annagav@users.noreply.github.com>
Date: Wed, 4 Oct 2023 16:06:04 -0400
Subject: [PATCH] Catalog Page: Add content loader  (#1941)

---
 .../public/src/components/CourseLoader.js     | 19 ++++++++++
 .../src/containers/pages/CatalogPage.js       | 36 ++++++++++---------
 package.json                                  |  5 ++-
 yarn.lock                                     | 11 ++++++
 4 files changed, 54 insertions(+), 17 deletions(-)
 create mode 100644 frontend/public/src/components/CourseLoader.js

diff --git a/frontend/public/src/components/CourseLoader.js b/frontend/public/src/components/CourseLoader.js
new file mode 100644
index 0000000000..d4fc0320f2
--- /dev/null
+++ b/frontend/public/src/components/CourseLoader.js
@@ -0,0 +1,19 @@
+import React from "react"
+import ContentLoader from "react-content-loader"
+
+const CourseLoader = props => (
+  <ContentLoader
+    width={305}
+    height={229}
+    viewBox="0 0 305 229"
+    backgroundColor="#f0f0f0"
+    foregroundColor="#dedede"
+    {...props}
+  >
+    <rect x="0" y="150" rx="4" ry="4" width="271" height="9" />
+    <rect x="0" y="170" rx="3" ry="3" width="119" height="6" />
+    <rect x="0" y="0" rx="10" ry="10" width="303" height="142" />
+  </ContentLoader>
+)
+
+export default CourseLoader
diff --git a/frontend/public/src/containers/pages/CatalogPage.js b/frontend/public/src/containers/pages/CatalogPage.js
index e74b1b80f3..aea0546203 100644
--- a/frontend/public/src/containers/pages/CatalogPage.js
+++ b/frontend/public/src/containers/pages/CatalogPage.js
@@ -28,6 +28,7 @@ import { compose } from "redux"
 import { connect } from "react-redux"
 import { connectRequest, requestAsync } from "redux-query"
 import { pathOr } from "ramda"
+import CourseLoader from "../../components/CourseLoader"
 
 type Props = {
   coursesIsLoading: ?boolean,
@@ -297,7 +298,7 @@ export class CatalogPage extends React.Component<Props> {
   }
 
   /**
-   * This is a comparision method used to sort an array of Course Runs
+   * This is a comparison method used to sort an array of Course Runs
    * from earliest start date to latest start date.
    * @param {BaseCourseRun} courseRunA The first Course Run to compare.
    * @param {BaseCourseRun} courseRunB The second Course Run to compare.
@@ -487,17 +488,22 @@ export class CatalogPage extends React.Component<Props> {
    * Renders the entire catalog of course or program cards based on the catalog tab selected.
    */
   renderCatalog() {
+    const { filteredCourses, filteredPrograms, tabSelected } = this.state
+
     if (
-      this.state.tabSelected === COURSES_TAB &&
-      this.state.filteredCourses.length > 0
+      filteredCourses.length === 0 &&
+      (this.props.coursesIsLoading || this.props.programsIsLoading)
     ) {
+      return courseLoaderGrid
+    }
+    if (tabSelected === COURSES_TAB && filteredCourses.length > 0) {
       return this.renderCatalogRows(
-        this.state.filteredCourses,
+        filteredCourses,
         this.renderCourseCatalogCard.bind(this)
       )
-    } else if (this.state.tabSelected === PROGRAMS_TAB) {
+    } else if (tabSelected === PROGRAMS_TAB) {
       return this.renderCatalogRows(
-        this.state.filteredPrograms,
+        filteredPrograms,
         this.renderProgramCatalogCard.bind(this)
       )
     }
@@ -645,16 +651,7 @@ export class CatalogPage extends React.Component<Props> {
                     </CSSTransition>
                   </TransitionGroup>
                 </div>
-                <div
-                  className={`${
-                    this.state.isLoadingMoreItems ? "lds-ring" : "d-none"
-                  }`}
-                >
-                  <div></div>
-                  <div></div>
-                  <div></div>
-                  <div></div>
-                </div>
+                {this.state.isLoadingMoreItems ? courseLoaderGrid : null}
                 {/* span is used to detect when the learner has scrolled to the bottom of the catalog page. */}
                 <span ref={this.container}></span>
               </div>
@@ -665,6 +662,13 @@ export class CatalogPage extends React.Component<Props> {
     )
   }
 }
+const courseLoaderGrid = (
+  <div id="catalog-grid">
+    <CourseLoader />
+    <CourseLoader />
+    <CourseLoader />
+  </div>
+)
 
 const getNextCoursePage = page =>
   requestAsync({
diff --git a/package.json b/package.json
index 570e813c9c..ab3d150d5f 100644
--- a/package.json
+++ b/package.json
@@ -8,5 +8,8 @@
         "build": "yarn workspaces foreach run build"
     },
     "version": "0.0.0",
-    "packageManager": "yarn@3.2.0"
+    "packageManager": "yarn@3.2.0",
+    "dependencies": {
+        "react-content-loader": "^6.2.1"
+    }
 }
diff --git a/yarn.lock b/yarn.lock
index e77553834f..b53cf84f52 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -13644,6 +13644,8 @@ __metadata:
 "mitx-online-root@workspace:.":
   version: 0.0.0-use.local
   resolution: "mitx-online-root@workspace:."
+  dependencies:
+    react-content-loader: ^6.2.1
   languageName: unknown
   linkType: soft
 
@@ -16829,6 +16831,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"react-content-loader@npm:^6.2.1":
+  version: 6.2.1
+  resolution: "react-content-loader@npm:6.2.1"
+  peerDependencies:
+    react: ">=16.0.0"
+  checksum: f777d408256a4218677e47f4cf3988d9fd8e556450e9b85ee1eb3952a5d5802573cea0df5eaf4dbc936c9522f355657de6f8ab0ecdf035d7dccdef15b45c9dae
+  languageName: node
+  linkType: hard
+
 "react-day-picker@npm:7.4.10":
   version: 7.4.10
   resolution: "react-day-picker@npm:7.4.10"