Merge pull request #10019 from Snuffleupagus/eventBusDispatchToDOM

Add general support for re-dispatching events, on `EventBus` instances, to the DOM

extensions/chromium/preferences_schema.json

@@ -47,6 +47,10 @@
       "type": "boolean",
       "default": false
     },
+    "eventBusDispatchToDOM": {
+      "type": "boolean",
+      "default": false
+    },
     "pdfBugEnabled": {
       "title": "Enable debugging tools",
       "description": "Whether to enable debugging tools.",

test/unit/ui_utils_spec.js

@@ -262,6 +262,45 @@ describe('ui_utils', function() {
       eventBus.dispatch('test');
       expect(count).toEqual(2);
     });
+
+    it('should not, by default, re-dispatch to DOM', function(done) {
+      if (isNodeJS()) {
+        pending('Document in not supported in Node.js.');
+      }
+      const eventBus = new EventBus();
+      let count = 0;
+      eventBus.on('test', function() {
+        count++;
+      });
+      document.addEventListener('test', function() {
+        count++;
+      });
+      eventBus.dispatch('test');
+
+      Promise.resolve().then(() => {
+        expect(count).toEqual(1);
+        done();
+      });
+    });
+    it('should re-dispatch to DOM', function(done) {
+      if (isNodeJS()) {
+        pending('Document in not supported in Node.js.');
+      }
+      const eventBus = new EventBus({ dispatchToDOM: true, });
+      let count = 0;
+      eventBus.on('test', function() {
+        count++;
+      });
+      document.addEventListener('test', function() {
+        count++;
+      });
+      eventBus.dispatch('test');
+
+      Promise.resolve().then(() => {
+        expect(count).toEqual(2);
+        done();
+      });
+    });
   });
 
   describe('isValidRotation', function() {

web/app.js

@@ -160,7 +160,7 @@ let PDFViewerApplication = {
       this.l10n.translate(appContainer).then(() => {
         // Dispatch the 'localized' event on the `eventBus` once the viewer
         // has been fully initialized and translated.
-        this.eventBus.dispatch('localized');
+        this.eventBus.dispatch('localized', { source: this, });
       });
 
       this.initialized = true;
@@ -288,7 +288,8 @@ let PDFViewerApplication = {
     return new Promise((resolve, reject) => {
       this.overlayManager = new OverlayManager();
 
-      let eventBus = appConfig.eventBus || getGlobalEventBus();
+      const dispatchToDOM = AppOptions.get('eventBusDispatchToDOM');
+      let eventBus = appConfig.eventBus || getGlobalEventBus(dispatchToDOM);
       this.eventBus = eventBus;
 
       let pdfRenderingQueue = new PDFRenderingQueue();
@@ -897,6 +898,9 @@ let PDFViewerApplication = {
       this.loadingBar.hide();
 
       firstPagePromise.then(() => {
+        this.eventBus.dispatch('documentloaded', { source: this, });
+        // TODO: Remove the following event, i.e. 'documentload',
+        //       once the mozilla-central tests have been updated.
         this.eventBus.dispatch('documentload', { source: this, });
       });
     });
@@ -1000,6 +1004,7 @@ let PDFViewerApplication = {
         this.setInitialView(hash, {
           rotation, sidebarView, scrollMode, spreadMode,
         });
+        this.eventBus.dispatch('documentinit', { source: this, });
 
         // Make all navigation keys work on document load,
         // unless the viewer is embedded in a web page.
@@ -1371,14 +1376,15 @@ let PDFViewerApplication = {
     };
     _boundEvents.windowHashChange = () => {
       eventBus.dispatch('hashchange', {
+        source: window,
         hash: document.location.hash.substring(1),
       });
     };
     _boundEvents.windowBeforePrint = () => {
-      eventBus.dispatch('beforeprint');
+      eventBus.dispatch('beforeprint', { source: window, });
     };
     _boundEvents.windowAfterPrint = () => {
-      eventBus.dispatch('afterprint');
+      eventBus.dispatch('afterprint', { source: window, });
     };
 
     window.addEventListener('wheel', webViewerWheel);
@@ -1560,6 +1566,7 @@ function webViewerInitialized() {
         return;
       }
       PDFViewerApplication.eventBus.dispatch('fileinputchange', {
+        source: this,
         fileInput: evt.target,
       });
     });
@@ -1578,6 +1585,7 @@ function webViewerInitialized() {
         return;
       }
       PDFViewerApplication.eventBus.dispatch('fileinputchange', {
+        source: this,
         fileInput: evt.dataTransfer,
       });
     });

web/app_options.js

@@ -68,6 +68,11 @@ const defaultOptions = {
     value: false,
     kind: OptionKind.VIEWER,
   },
+  eventBusDispatchToDOM: {
+    /** @type {boolean} */
+    value: false,
+    kind: OptionKind.VIEWER,
+  },
   externalLinkRel: {
     /** @type {string} */
     value: 'noopener noreferrer nofollow',

web/default_preferences.json

@@ -4,6 +4,7 @@
   "sidebarViewOnLoad": 0,
   "cursorToolOnLoad": 0,
   "enableWebGL": false,
+  "eventBusDispatchToDOM": false,
   "pdfBugEnabled": false,
   "disableRange": false,
   "disableStream": false,

web/dom_events.js

@@ -129,12 +129,13 @@ function attachDOMEventsToEventBus(eventBus) {
 }
 
 let globalEventBus = null;
-function getGlobalEventBus() {
+function getGlobalEventBus(dispatchToDOM = false) {
-  if (globalEventBus) {
+  if (!globalEventBus) {
-    return globalEventBus;
+    globalEventBus = new EventBus({ dispatchToDOM, });
+    if (!dispatchToDOM) {
+      attachDOMEventsToEventBus(globalEventBus);
+    }
   }
-  globalEventBus = new EventBus();
-  attachDOMEventsToEventBus(globalEventBus);
   return globalEventBus;
 }
 

web/pdf_presentation_mode.js

@@ -60,19 +60,19 @@ class PDFPresentationMode {
     if (contextMenuItems) {
       contextMenuItems.contextFirstPage.addEventListener('click', () => {
         this.contextMenuOpen = false;
-        this.eventBus.dispatch('firstpage');
+        this.eventBus.dispatch('firstpage', { source: this, });
       });
       contextMenuItems.contextLastPage.addEventListener('click', () => {
         this.contextMenuOpen = false;
-        this.eventBus.dispatch('lastpage');
+        this.eventBus.dispatch('lastpage', { source: this, });
       });
       contextMenuItems.contextPageRotateCw.addEventListener('click', () => {
         this.contextMenuOpen = false;
-        this.eventBus.dispatch('rotatecw');
+        this.eventBus.dispatch('rotatecw', { source: this, });
       });
       contextMenuItems.contextPageRotateCcw.addEventListener('click', () => {
         this.contextMenuOpen = false;
-        this.eventBus.dispatch('rotateccw');
+        this.eventBus.dispatch('rotateccw', { source: this, });
       });
     }
   }

web/toolbar.js

@@ -100,19 +100,19 @@ class Toolbar {
     let self = this;
 
     items.previous.addEventListener('click', function() {
-      eventBus.dispatch('previouspage');
+      eventBus.dispatch('previouspage', { source: self, });
     });
 
     items.next.addEventListener('click', function() {
-      eventBus.dispatch('nextpage');
+      eventBus.dispatch('nextpage', { source: self, });
     });
 
     items.zoomIn.addEventListener('click', function() {
-      eventBus.dispatch('zoomin');
+      eventBus.dispatch('zoomin', { source: self, });
     });
 
     items.zoomOut.addEventListener('click', function() {
-      eventBus.dispatch('zoomout');
+      eventBus.dispatch('zoomout', { source: self, });
     });
 
     items.pageNumber.addEventListener('click', function() {
@@ -137,19 +137,19 @@ class Toolbar {
     });
 
     items.presentationModeButton.addEventListener('click', function() {
-      eventBus.dispatch('presentationmode');
+      eventBus.dispatch('presentationmode', { source: self, });
     });
 
     items.openFile.addEventListener('click', function() {
-      eventBus.dispatch('openfile');
+      eventBus.dispatch('openfile', { source: self, });
     });
 
     items.print.addEventListener('click', function() {
-      eventBus.dispatch('print');
+      eventBus.dispatch('print', { source: self, });
     });
 
     items.download.addEventListener('click', function() {
-      eventBus.dispatch('download');
+      eventBus.dispatch('download', { source: self, });
     });
 
     // Suppress context menus for some controls.

web/ui_utils.js

@@ -683,8 +683,9 @@ let animationStarted = new Promise(function (resolve) {
  * used.
  */
 class EventBus {
-  constructor() {
+  constructor({ dispatchToDOM = false, } = {}) {
     this._listeners = Object.create(null);
+    this._dispatchToDOM = dispatchToDOM === true;
   }
 
   on(eventName, listener) {
@@ -708,6 +709,9 @@ class EventBus {
   dispatch(eventName) {
     let eventListeners = this._listeners[eventName];
     if (!eventListeners || eventListeners.length === 0) {
+      if (this._dispatchToDOM) {
+        this._dispatchDOMEvent(eventName);
+      }
       return;
     }
     // Passing all arguments after the eventName to the listeners.
@@ -717,6 +721,35 @@ class EventBus {
     eventListeners.slice(0).forEach(function (listener) {
       listener.apply(null, args);
     });
+    if (this._dispatchToDOM) {
+      this._dispatchDOMEvent(eventName, args);
+    }
+  }
+
+  /**
+   * @private
+   */
+  _dispatchDOMEvent(eventName, args = null) {
+    if (!this._dispatchToDOM) {
+      return;
+    }
+    const details = Object.create(null);
+    if (args && args.length > 0) {
+      const obj = args[0];
+      for (let key in obj) {
+        const value = obj[key];
+        if (key === 'source') {
+          if (value === window || value === document) {
+            return; // No need to re-dispatch (already) global events.
+          }
+          continue; // Ignore the `source` property.
+        }
+        details[key] = value;
+      }
+    }
+    const event = document.createEvent('CustomEvent');
+    event.initCustomEvent(eventName, true, true, details);
+    document.dispatchEvent(event);
   }
 }