feat(loading): Add options for loading icon and progress bar

src/lib/Preview.js

@@ -1175,10 +1175,6 @@ class Preview extends EventEmitter {
             this.ui.showLoadingDownloadButton(this.download);
         }
 
-        // Update the loading indicators
-        this.ui.hideCrawler();
-        this.ui.setLoadingIcon(this.file.extension);
-
         // Determine the asset loader to use
         const loader = this.getLoader(this.file);
 

src/lib/__tests__/Preview-test.js

@@ -1666,8 +1666,6 @@ describe('lib/Preview', () => {
             stubs.destroy = jest.spyOn(preview, 'destroy');
             stubs.checkPermission = jest.spyOn(file, 'checkPermission').mockReturnValue(true);
             stubs.canDownload = jest.spyOn(file, 'canDownload').mockReturnValue(false);
-            stubs.hideCrawler = jest.spyOn(preview.ui, 'hideCrawler').mockImplementation();
-            stubs.setLoadingIcon = jest.spyOn(preview.ui, 'setLoadingIcon').mockImplementation();
             stubs.showLoadingDownloadButton = jest.spyOn(preview.ui, 'showLoadingDownloadButton').mockImplementation();
             stubs.loadPromiseResolve = Promise.resolve();
             stubs.determineRepresentationStatusPromise = Promise.resolve();
@@ -1715,27 +1713,16 @@ describe('lib/Preview', () => {
 
         test('should show the loading download button if file can be downloaded', () => {
             stubs.canDownload.mockReturnValue(true);
-            preview.loadViewer();
+            preview.loadViewer({});
             expect(stubs.showLoadingDownloadButton).toBeCalled();
         });
 
         test("should not show the loading download button if file can't be downloaded", () => {
             stubs.canDownload.mockReturnValue(false);
-            preview.loadViewer();
+            preview.loadViewer({});
             expect(stubs.showLoadingDownloadButton).not.toBeCalled();
         });
 
-        test('should show the file-specific loading icon', () => {
-            preview.file.extension = 'pdf';
-            preview.loadViewer();
-            expect(stubs.setLoadingIcon).toBeCalledWith('pdf');
-        });
-
-        test('should hide the loading crawler', () => {
-            preview.loadViewer();
-            expect(stubs.hideCrawler).toBeCalled();
-        });
-
         test('should throw an unsupported error if there is no loader for general file types', () => {
             stubs.getLoader.mockReturnValue(undefined);
 

src/lib/viewers/BaseViewer.js

@@ -194,6 +194,9 @@ class BaseViewer extends EventEmitter {
         // From the perspective of viewers bp-content holds everything
         this.containerEl = container.querySelector(SELECTOR_BOX_PREVIEW_CONTENT);
 
+        // Update the loading indicators
+        this.setupLoading();
+
         // Attach event listeners
         this.addCommonListeners();
 
@@ -220,6 +223,20 @@ class BaseViewer extends EventEmitter {
         this.isSetup = true;
     }
 
+    /**
+     * Removes the crawler and sets the file type specific loading icon
+     *
+     * @return {void}
+     */
+    setupLoading() {
+        const { file = {} } = this.options;
+
+        if (this.previewUI) {
+            this.previewUI.hideCrawler();
+            this.previewUI.setLoadingIcon(file.extension);
+        }
+    }
+
     /**
      * Destroys the viewer
      *

src/lib/viewers/__tests__/BaseViewer-test.js

@@ -37,11 +37,13 @@ describe('lib/viewers/BaseViewer', () => {
             },
         });
         base.previewUI = {
-            replaceHeader: jest.fn(),
+            hideCrawler: jest.fn(),
             notification: {
                 show: jest.fn(),
                 hide: jest.fn(),
             },
+            replaceHeader: jest.fn(),
+            setLoadingIcon: jest.fn(),
         };
     });
 
@@ -116,6 +118,17 @@ describe('lib/viewers/BaseViewer', () => {
         });
     });
 
+    describe('setupLoading()', () => {
+        test('should hide the crawler and set the file-specific loading icon', () => {
+            base.options.file = { extension: 'pdf' };
+
+            base.setupLoading();
+
+            expect(base.previewUI.hideCrawler).toBeCalled();
+            expect(base.previewUI.setLoadingIcon).toBeCalledWith('pdf');
+        });
+    });
+
     describe('getResizeHandler()', () => {
         test('should return a resize handler', () => {
             expect(typeof base.getResizeHandler()).toBe('function');

src/lib/viewers/error/PreviewErrorViewer.js

@@ -44,7 +44,7 @@ class PreviewErrorViewer extends BaseViewer {
      * @override
      * @return {void}
      */
-    finishLoadingSetup() {
+    setupLoading() {
         /* no op, custom loading logic for errors */
     }