Removes lastScrollSource and isViewerInPresentationMode from TextLaye…

…rBuilderOptions

web/interfaces.js

@@ -73,17 +73,6 @@ IRenderableView.prototype = {
   resume: function () {},
 };
 
-/**
- * @interface
- */
-function ILastScrollSource() {}
-ILastScrollSource.prototype = {
-  /**
-   * @returns {number}
-   */
-  get lastScroll() {},
-};
-
 /**
  * @interface
  */

web/pdf_find_controller.js

@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-/* globals PDFJS, FirefoxCom, Promise */
+/* globals PDFJS, FirefoxCom, Promise, scrollIntoView */
 
 'use strict';
 
@@ -24,6 +24,9 @@ var FindStates = {
   FIND_PENDING: 3
 };
 
+var FIND_SCROLL_OFFSET_TOP = -50;
+var FIND_SCROLL_OFFSET_LEFT = -400;
+
 /**
  * Provides "search" or "find" functionality for the PDF.
  * This object actually performs the search for a given string.
@@ -308,6 +311,26 @@ var PDFFindController = (function PDFFindControllerClosure() {
       }
     },
 
+    /**
+     * The method is called back from the text layer when match presentation
+     * is updated.
+     * @param {number} pageIndex - page index.
+     * @param {number} index - match index.
+     * @param {Array} elements - text layer div elements array.
+     * @param {number} beginIdx - start index of the div array for the match.
+     * @param {number} endIdx - end index of the div array for the match.
+     */
+    updateMatchPosition: function PDFFindController_updateMatchPosition(
+        pageIndex, index, elements, beginIdx, endIdx) {
+      if (this.selected.matchIdx === index &&
+          this.selected.pageIdx === pageIndex) {
+        scrollIntoView(elements[beginIdx], {
+          top: FIND_SCROLL_OFFSET_TOP,
+          left: FIND_SCROLL_OFFSET_LEFT
+        });
+      }
+    },
+
     nextPageMatch: function PDFFindController_nextPageMatch() {
       if (this.resumePageIdx !== null) {
         console.error('There can only be one pending page.');

web/pdf_page_view.js

@@ -18,6 +18,8 @@
 
 'use strict';
 
+var TEXT_LAYER_RENDER_DELAY = 200; // ms
+
 /**
  * @typedef {Object} PDFPageViewOptions
  * @property {HTMLDivElement} container - The viewer element.
@@ -194,6 +196,15 @@ var PDFPageView = (function PDFPageViewClosure() {
       this.reset(true);
     },
 
+    /**
+     * Called when moved in the parent's container.
+     */
+    updatePosition: function PDFPageView_updatePosition() {
+      if (this.textLayer) {
+        this.textLayer.render(TEXT_LAYER_RENDER_DELAY);
+      }
+    },
+
     cssTransform: function PDFPageView_transform(canvas, redrawAnnotations) {
       // Scale canvas, canvas wrapper, and page container.
       var width = this.viewport.width;
@@ -429,6 +440,7 @@ var PDFPageView = (function PDFPageViewClosure() {
             self.pdfPage.getTextContent().then(
               function textContentResolved(textContent) {
                 textLayer.setTextContent(textContent);
+                textLayer.render(TEXT_LAYER_RENDER_DELAY);
               }
             );
           }

web/pdf_viewer.js

@@ -49,7 +49,6 @@ var DEFAULT_CACHE_SIZE = 10;
 /**
  * Simple viewer control to display PDF content/pages.
  * @class
- * @implements {ILastScrollSource}
  * @implements {IRenderableView}
  */
 var PDFViewer = (function pdfViewer() {
@@ -92,7 +91,6 @@ var PDFViewer = (function pdfViewer() {
     }
 
     this.scroll = watchScroll(this.container, this._scrollUpdate.bind(this));
-    this.lastScroll = 0;
     this.updateInProgress = false;
     this.presentationModeState = PresentationModeState.UNKNOWN;
     this._resetView();
@@ -333,12 +331,13 @@ var PDFViewer = (function pdfViewer() {
     },
 
     _scrollUpdate: function () {
-      this.lastScroll = Date.now();
-
       if (this.pagesCount === 0) {
         return;
       }
       this.update();
+      for (var i = 0, ii = this.pages.length; i < ii; i++) {
+        this.pages[i].updatePosition();
+      }
     },
 
     _setScaleUpdatePages: function pdfViewer_setScaleUpdatePages(
@@ -696,9 +695,7 @@ var PDFViewer = (function pdfViewer() {
         textLayerDiv: textLayerDiv,
         pageIndex: pageIndex,
         viewport: viewport,
-        lastScrollSource: this,
-        isViewerInPresentationMode: isViewerInPresentationMode,
-        findController: this.findController
+        findController: isViewerInPresentationMode ? null : this.findController
       });
     },
 

web/text_layer_builder.js

@@ -13,14 +13,11 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-/* globals CustomStyle, scrollIntoView, PDFJS */
+/* globals CustomStyle, PDFJS */
 
 'use strict';
 
-var FIND_SCROLL_OFFSET_TOP = -50;
-var FIND_SCROLL_OFFSET_LEFT = -400;
 var MAX_TEXT_DIVS_TO_RENDER = 100000;
-var RENDER_DELAY = 200; // ms
 
 var NonWhitespaceRegexp = /\S/;
 
@@ -33,9 +30,6 @@ function isAllWhitespace(str) {
  * @property {HTMLDivElement} textLayerDiv - The text layer container.
  * @property {number} pageIndex - The page index.
  * @property {PageViewport} viewport - The viewport of the text layer.
- * @property {ILastScrollSource} lastScrollSource - The object that records when
- *   last time scroll happened.
- * @property {boolean} isViewerInPresentationMode
  * @property {PDFFindController} findController
  */
 
@@ -49,13 +43,11 @@ function isAllWhitespace(str) {
 var TextLayerBuilder = (function TextLayerBuilderClosure() {
   function TextLayerBuilder(options) {
     this.textLayerDiv = options.textLayerDiv;
-    this.layoutDone = false;
+    this.renderingDone = false;
     this.divContentDone = false;
     this.pageIdx = options.pageIndex;
     this.matches = [];
-    this.lastScrollSource = options.lastScrollSource || null;
     this.viewport = options.viewport;
-    this.isViewerInPresentationMode = options.isViewerInPresentationMode;
     this.textDivs = [];
     this.findController = options.findController || null;
   }
@@ -71,6 +63,7 @@ var TextLayerBuilder = (function TextLayerBuilderClosure() {
       // No point in rendering many divs as it would make the browser
       // unusable even after the divs are rendered.
       if (textDivsLength > MAX_TEXT_DIVS_TO_RENDER) {
+        this.renderingDone = true;
         return;
       }
 
@@ -118,23 +111,29 @@ var TextLayerBuilder = (function TextLayerBuilderClosure() {
       this.updateMatches();
     },
 
-    setupRenderLayoutTimer:
-        function TextLayerBuilder_setupRenderLayoutTimer() {
-      // Schedule renderLayout() if the user has been scrolling,
-      // otherwise run it right away.
-      var self = this;
-      var lastScroll = (this.lastScrollSource === null ?
-                        0 : this.lastScrollSource.lastScroll);
+    /**
+     * Renders the text layer.
+     * @param {number} timeout (optional) if specified, the rendering waits
+     *   for specified amount of ms.
+     */
+    render: function TextLayerBuilder_render(timeout) {
+      if (!this.divContentDone || this.renderingDone) {
+        return;
+      }
 
-      if (Date.now() - lastScroll > RENDER_DELAY) { // Render right away
+      if (this.renderTimer) {
+        clearTimeout(this.renderTimer);
+        this.renderTimer = null;
+      }
+
+      if (!timeout) { // Render right away
         this.renderLayer();
       } else { // Schedule
-        if (this.renderTimer) {
-          clearTimeout(this.renderTimer);
-        }
+        var self = this;
         this.renderTimer = setTimeout(function() {
-          self.setupRenderLayoutTimer();
-        }, RENDER_DELAY);
+          self.renderLayer();
+          self.renderTimer = null;
+        }, timeout);
       }
     },
 
@@ -204,7 +203,6 @@ var TextLayerBuilder = (function TextLayerBuilderClosure() {
         this.appendText(textItems[i], textContent.styles);
       }
       this.divContentDone = true;
-      this.setupRenderLayoutTimer();
     },
 
     convertMatches: function TextLayerBuilder_convertMatches(matches) {
@@ -266,8 +264,9 @@ var TextLayerBuilder = (function TextLayerBuilderClosure() {
       var bidiTexts = this.textContent.items;
       var textDivs = this.textDivs;
       var prevEnd = null;
+      var pageIdx = this.pageIdx;
       var isSelectedPage = (this.findController === null ?
-        false : (this.pageIdx === this.findController.selected.pageIdx));
+        false : (pageIdx === this.findController.selected.pageIdx));
       var selectedMatchIdx = (this.findController === null ?
                               -1 : this.findController.selected.matchIdx);
       var highlightAll = (this.findController === null ?
@@ -313,10 +312,9 @@ var TextLayerBuilder = (function TextLayerBuilderClosure() {
         var isSelected = (isSelectedPage && i === selectedMatchIdx);
         var highlightSuffix = (isSelected ? ' selected' : '');
 
-        if (isSelected && !this.isViewerInPresentationMode) {
-          scrollIntoView(textDivs[begin.divIdx],
-                         { top: FIND_SCROLL_OFFSET_TOP,
-                           left: FIND_SCROLL_OFFSET_LEFT });
+        if (this.findController) {
+          this.findController.updateMatchPosition(pageIdx, i, textDivs,
+                                                  begin.divIdx, end.divIdx);
         }
 
         // Match inside new div.