Print Preview: Hiding header/footer options when 'no margins' is selected

chrome/browser/resources/print_preview/header_footer_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 HeaderFooterSettings object. This object encapsulates all
    * settings and logic related to the headers and footers checkbox.
    * @constructor
    */
   function HeaderFooterSettings() {
     this.headerFooterOption_ = $('header-footer-option');
     this.headerFooterCheckbox_ = $('header-footer');
+    this.headerFooterApplies_;

[Lei Zhang, 2011/11/29 19:45:15]

do you need to initialize this here?

[dpapad, 2011/11/29 20:40:26]

Done. This is supposed to be initialized elsewhere (in
onMarginsSelectionChanged_) before being used, so I had it like that to check if
that is true.

     this.addEventListeners_();
   }
 
   cr.addSingletonGetter(HeaderFooterSettings);
 
   HeaderFooterSettings.prototype = {
     /**
      * The checkbox corresponding to the headers and footers option.
      * @type {HTMLInputElement}
      */
     get headerFooterCheckbox() {
       return this.headerFooterCheckbox_;
     },
 
     /**
      * Checks whether the Headers and Footers checkbox is checked or not.
      * @return {boolean} true if Headers and Footers are checked.
      */
     hasHeaderFooter: function() {
-      return this.headerFooterCheckbox_.checked;
+      return this.headerFooterApplies_ && this.headerFooterCheckbox_.checked;
     },
 
     /**
      * Adding listeners to header footer related controls.
      * @private
      */
     addEventListeners_: function() {
       this.headerFooterCheckbox_.onclick =
           this.onHeaderFooterChanged_.bind(this);
       document.addEventListener(customEvents.PDF_LOADED,
                                 this.onPDFLoaded_.bind(this));
+      document.addEventListener(customEvents.MARGINS_SELECTION_CHANGED,
+                                this.onMarginsSelectionChanged_.bind(this));
+    },
+
+    onMarginsSelectionChanged_: function(event) {
+      this.headerFooterApplies_ = event.selectedMargins !=
+          print_preview.MarginSettings.MARGINS_VALUE_NO_MARGINS
+      this.setVisible_(this.headerFooterApplies_);
     },
 
     /**
      * Listener executing when the user selects or de-selects the headers
      * and footers option.
      * @private
      */
     onHeaderFooterChanged_: function() {
       requestPrintPreview();
     },
 
     /**
      * Listener executing when a |customEvents.PDF_LOADED| event occurs.
      * @private
      */
     onPDFLoaded_: function() {
-      if (!previewModifiable) {
+      if (!previewModifiable)
+        this.setVisible_(previewModifiable);

[Lei Zhang, 2011/11/29 19:45:15]

isn't this always false here?

[dpapad, 2011/11/29 20:40:26]

Done.

+    },
+
+    /**
+     * Hides or shows |this.headerFooterOption|.
+     * @{param} visible True if |this.headerFooterOption| should be shown.
+     * @private
+     */
+    setVisible_: function(visible) {
+      if (visible)
+        fadeInOption(this.headerFooterOption_);
+      else
         fadeOutOption(this.headerFooterOption_);
-        this.headerFooterCheckbox_.checked = false;
-      }
     },
   };
 
   return {
     HeaderFooterSettings: HeaderFooterSettings,
   };
 });