Print Preview: Fixing behavior of event listeners.

chrome/browser/resources/print_preview/layout_settings.js

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.define('print_preview', function() {
   'use strict';
 
   /**
    * Creates a LayoutSettings object. This object encapsulates all settings and
    * logic related to layout mode (portrait/landscape).
    * @constructor
    */
   function LayoutSettings() {
     this.layoutOption_ = $('layout-option');
     this.portraitRadioButton_ = $('portrait');
     this.landscapeRadioButton_ = $('landscape');
+    this.wasLandscape_ = false;
+    this.updateState();
   }
 
   cr.addSingletonGetter(LayoutSettings);
 
   LayoutSettings.prototype = {
     /**
      * The radio button corresponding to the portrait option.
      * @type {HTMLInputElement}
      */
     get portraitRadioButton() {
@@ skipping 10 matching lines @@
 
     /**
      * @return {boolean} true if |this.landscapeRadioButton_| is checked, false
      *     if not.
      */
     isLandscape: function() {
       return this.landscapeRadioButton_.checked;
     },
 
     /**
+     * @return {boolean} true if the chosen layout mode has changed since last
+     *     time the state was updated.
+     */
+    hasChanged_ : function() {
+      return this.isLandscape() !=  this.wasLandscape_;
+    },
+
+    /**
+     * Saves the currently selected layout mode. Used  in |this.hasChanged_|.
+     */
+    updateState : function() {
+      this.wasLandscape_ = this.isLandscape();
+    },
+
+    /**
      * Adding listeners to all layout related controls. The listeners take care
      * of altering their behavior depending on |hasPendingPreviewRequest|.
      */
     addEventListeners: function() {
-      this.landscapeRadioButton_.onclick = function() {
-        if (!hasPendingPreviewRequest)
-          this.onLayoutButtonClick_();
-      }.bind(this);
-      this.portraitRadioButton_.onclick = function() {
-        if (!hasPendingPreviewRequest)
-          this.onLayoutButtonClick_();
-      }.bind(this);
+      this.landscapeRadioButton_.onclick = this.onLayoutButtonClick_.bind(this);
+      this.portraitRadioButton_.onclick = this.onLayoutButtonClick_.bind(this);
       document.addEventListener('PDFLoaded', this.onPDFLoaded_.bind(this));
       document.addEventListener('printerCapabilitiesUpdated',
                                 this.onPrinterCapabilitiesUpdated_.bind(this));
     },
 
     /**
      * Listener triggered when a printerCapabilitiesUpdated event occurs.
      * @private
      */
     onPrinterCapabilitiesUpdated_: function(e) {
       if (e.printerCapabilities.disableLandscapeOption)
         this.fadeInOut_(e.printerCapabilities.disableLandscapeOption);
     },
 
     /**
      * Listener executing when |this.landscapeRadioButton_| or
      * |this.portraitRadioButton_| is clicked.
      * @private
      */
     onLayoutButtonClick_: function() {
       // If the chosen layout is same as before, nothing needs to be done.
-      if (printSettings.isLandscape == this.isLandscape())
-        return;
-      setDefaultValuesAndRegeneratePreview();
+      if (this.hasChanged_())
+        setDefaultValuesAndRegeneratePreview();
     },
 
     /**
      * Listener executing when a PDFLoaded event occurs.
      * @private
      */
     onPDFLoaded_: function() {
-      if (!previewModifiable)
-        fadeOutElement(this.layoutOption_);
+      this.fadeInOut_(!previewModifiable);
     },
 
     /**
      * @param {boolean} fadeOut True if |this.layoutOption_| should be faded
      *     out, false if it should be faded in.
      * @private
      */
     fadeInOut_: function(fadeOut) {
       fadeOut ? fadeOutElement(this.layoutOption_) :
           fadeInElement(this.layoutOption_);
     }
   };
 
   return {
     LayoutSettings: LayoutSettings,
   };
 });