Add a `enhanceTextSelection` preference to the viewer

extensions/chromium/preferences_schema.json

@@ -94,6 +94,10 @@
       "type": "boolean",
       "description": "Whether to prevent the extension from reporting the extension and browser version to the extension developers.",
       "default": false
+    },
+    "enhanceTextSelection": {
+      "type": "boolean",
+      "default": false
     }
   }
 }

web/app.js

@@ -101,7 +101,6 @@ var SCALE_SELECT_CONTAINER_PADDING = 8;
 var SCALE_SELECT_PADDING = 22;
 var PAGE_NUMBER_LOADING_INDICATOR = 'visiblePageIsLoading';
 var DISABLE_AUTO_FETCH_LOADING_BAR_TIMEOUT = 5000;
-var ENHANCE_TEXT_SELECTION = false;
 
 function configure(PDFJS) {
   PDFJS.imageResourcesPath = './images/';
@@ -177,6 +176,7 @@ var PDFViewerApplication = {
   preferencePdfBugEnabled: false,
   preferenceShowPreviousViewOnLoad: true,
   preferenceDefaultZoomValue: '',
+  preferenceEnhanceTextSelection: false,
   isViewerEmbedded: (window.parent !== window),
   url: '',
   externalServices: DefaultExernalServices,
@@ -206,6 +206,9 @@ var PDFViewerApplication = {
       Preferences.get('defaultZoomValue').then(function resolved(value) {
         self.preferenceDefaultZoomValue = value;
       }),
+      Preferences.get('enhanceTextSelection').then(function resolved(value) {
+        self.preferenceEnhanceTextSelection = value;
+      }),
       Preferences.get('disableTextLayer').then(function resolved(value) {
         if (PDFJS.disableTextLayer === true) {
           return;
@@ -274,7 +277,7 @@ var PDFViewerApplication = {
         renderingQueue: pdfRenderingQueue,
         linkService: pdfLinkService,
         downloadManager: downloadManager,
-        enhanceTextSelection: ENHANCE_TEXT_SELECTION,
+        enhanceTextSelection: this.preferenceEnhanceTextSelection,
       });
       pdfRenderingQueue.setViewer(this.pdfViewer);
       pdfLinkService.setViewer(this.pdfViewer);

web/default_preferences.json

@@ -11,5 +11,6 @@
   "disableFontFace": false,
   "disableTextLayer": false,
   "useOnlyCssZoom": false,
-  "externalLinkTarget": 0
+  "externalLinkTarget": 0,
+  "enhanceTextSelection": false
 }

web/text_layer_builder.js

@@ -36,7 +36,7 @@
  * @property {PageViewport} viewport - The viewport of the text layer.
  * @property {PDFFindController} findController
  * @property {boolean} enhanceTextSelection - Option to turn on improved
- *   text selection.
+ *   text selection. The default value is `false`.
  */
 
 /**
@@ -59,7 +59,7 @@ var TextLayerBuilder = (function TextLayerBuilderClosure() {
     this.textDivs = [];
     this.findController = options.findController || null;
     this.textLayerRenderTask = null;
-    this.enhanceTextSelection = options.enhanceTextSelection;
+    this.enhanceTextSelection = options.enhanceTextSelection || false;
     this._bindMouse();
   }