Merge pull request #4292 from Snuffleupagus/issue-4232

Fix wrong page being displayed when entering/exiting Presentation mode with zoom set to 'page-fit'

web/page_view.js

@@ -329,7 +329,12 @@ var PageView = function pageView(container, id, scale,
   };
 
   this.scrollIntoView = function pageViewScrollIntoView(dest) {
-    if (PresentationMode.active) { // Avoid breaking presentation mode.
+    if (PresentationMode.active) {
+      if (PDFView.page !== this.id) {
+        // Avoid breaking PDFView.getVisiblePages in presentation mode.
+        PDFView.page = this.id;
+        return;
+      }
       dest = null;
       PDFView.setScale(PDFView.currentScaleValue, true, true);
     }

web/viewer.js

@@ -1321,8 +1321,16 @@ var PDFView = {
   },
 
   getVisiblePages: function pdfViewGetVisiblePages() {
-    return this.getVisibleElements(this.container, this.pages,
+    if (!PresentationMode.active) {
-                                   !PresentationMode.active);
+      return this.getVisibleElements(this.container, this.pages, true);
+    } else {
+      // The algorithm in getVisibleElements doesn't work in all browsers and
+      // configurations when presentation mode is active.
+      var visible = [];
+      var currentPage = this.pages[this.page - 1];
+      visible.push({ id: currentPage.id, view: currentPage });
+      return { first: currentPage, last: currentPage, views: visible };
+    }
   },
 
   getVisibleThumbs: function pdfViewGetVisibleThumbs() {
@@ -1871,9 +1879,11 @@ function updateViewarea() {
     currentId = visiblePages[0].id;
   }
 
-  updateViewarea.inProgress = true; // used in "set page"
+  if (!PresentationMode.active) {
-  PDFView.page = currentId;
+    updateViewarea.inProgress = true; // used in "set page"
-  updateViewarea.inProgress = false;
+    PDFView.page = currentId;
+    updateViewarea.inProgress = false;
+  }
 
   var currentScale = PDFView.currentScale;
   var currentScaleValue = PDFView.currentScaleValue;