chrome/browser/chrome_page_zoom.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/chrome_page_zoom.h"
   6
   7 #include <algorithm>
   8 #include <cmath>
   9
  10 #include "base/prefs/pref_service.h"
  11 #include "chrome/browser/chrome_page_zoom_constants.h"
  12 #include "chrome/browser/profiles/profile.h"
  13 #include "chrome/browser/ui/zoom/zoom_controller.h"
  14 #include "chrome/common/pref_names.h"
  15 #include "content/public/browser/host_zoom_map.h"
  16 #include "content/public/browser/render_view_host.h"
  17 #include "content/public/browser/user_metrics.h"
  18 #include "content/public/browser/web_contents.h"
  19 #include "content/public/common/page_zoom.h"
  20 #include "content/public/common/renderer_preferences.h"
  21
  22 using base::UserMetricsAction;
  23
  24 namespace chrome_page_zoom {
  25
  26 enum PageZoomValueType {
  27   PAGE_ZOOM_VALUE_TYPE_FACTOR,
  28   PAGE_ZOOM_VALUE_TYPE_LEVEL,
  29 };
  30
  31 std::vector<double> PresetZoomValues(PageZoomValueType value_type,
  32                                      double custom_value) {
  33   // Generate a vector of zoom values from an array of known preset
  34   // factors. The values in content::kPresetZoomFactors will already be in
  35   // sorted order.
  36   std::vector<double> zoom_values;
  37   bool found_custom = false;
  38   for (size_t i = 0; i < kPresetZoomFactorsSize; i++) {
  39     double zoom_value = kPresetZoomFactors[i];
  40     if (value_type == PAGE_ZOOM_VALUE_TYPE_LEVEL)
  41       zoom_value = content::ZoomFactorToZoomLevel(zoom_value);
  42     if (content::ZoomValuesEqual(zoom_value, custom_value))
  43       found_custom = true;
  44     zoom_values.push_back(zoom_value);
  45   }
  46   // If the preset array did not contain the custom value, append it to the
  47   // vector and then sort.
  48   double min = value_type == PAGE_ZOOM_VALUE_TYPE_LEVEL ?
  49       content::ZoomFactorToZoomLevel(content::kMinimumZoomFactor) :
  50       content::kMinimumZoomFactor;
  51   double max = value_type == PAGE_ZOOM_VALUE_TYPE_LEVEL ?
  52       content::ZoomFactorToZoomLevel(content::kMaximumZoomFactor) :
  53       content::kMaximumZoomFactor;
  54   if (!found_custom && custom_value > min && custom_value < max) {
  55     zoom_values.push_back(custom_value);
  56     std::sort(zoom_values.begin(), zoom_values.end());
  57   }
  58   return zoom_values;
  59 }
  60
  61 std::vector<double> PresetZoomFactors(double custom_factor) {
  62   return PresetZoomValues(PAGE_ZOOM_VALUE_TYPE_FACTOR, custom_factor);
  63 }
  64
  65 std::vector<double> PresetZoomLevels(double custom_level) {
  66   return PresetZoomValues(PAGE_ZOOM_VALUE_TYPE_LEVEL, custom_level);
  67 }
  68
  69 void Zoom(content::WebContents* web_contents, content::PageZoom zoom) {
  70   ZoomController* zoom_controller =
  71       ZoomController::FromWebContents(web_contents);
  72   DCHECK(zoom_controller);
  73
  74   double current_zoom_level = zoom_controller->GetZoomLevel();
  75   double default_zoom_level =
  76       Profile::FromBrowserContext(web_contents->GetBrowserContext())->
  77           GetPrefs()->GetDouble(prefs::kDefaultZoomLevel);
  78
  79   if (zoom == content::PAGE_ZOOM_RESET) {
  80     zoom_controller->SetZoomLevel(default_zoom_level);
  81     content::RecordAction(UserMetricsAction("ZoomNormal"));
  82     return;
  83   }
  84
  85   // Generate a vector of zoom levels from an array of known presets along with
  86   // the default level added if necessary.
  87   std::vector<double> zoom_levels = PresetZoomLevels(default_zoom_level);
  88
  89   if (zoom == content::PAGE_ZOOM_OUT) {
  90     // Iterate through the zoom levels in reverse order to find the next
  91     // lower level based on the current zoom level for this page.
  92     for (std::vector<double>::reverse_iterator i = zoom_levels.rbegin();
  93          i != zoom_levels.rend(); ++i) {
  94       double zoom_level = *i;
  95       if (content::ZoomValuesEqual(zoom_level, current_zoom_level))
  96         continue;
  97       if (zoom_level < current_zoom_level) {
  98         zoom_controller->SetZoomLevel(zoom_level);
  99         content::RecordAction(UserMetricsAction("ZoomMinus"));
 100         return;
 101       }
 102       content::RecordAction(UserMetricsAction("ZoomMinus_AtMinimum"));
 103     }
 104   } else {
 105     // Iterate through the zoom levels in normal order to find the next
 106     // higher level based on the current zoom level for this page.
 107     for (std::vector<double>::const_iterator i = zoom_levels.begin();
 108          i != zoom_levels.end(); ++i) {
 109       double zoom_level = *i;
 110       if (content::ZoomValuesEqual(zoom_level, current_zoom_level))
 111         continue;
 112       if (zoom_level > current_zoom_level) {
 113         zoom_controller->SetZoomLevel(zoom_level);
 114         content::RecordAction(UserMetricsAction("ZoomPlus"));
 115         return;
 116       }
 117     }
 118     content::RecordAction(UserMetricsAction("ZoomPlus_AtMaximum"));
 119   }
 120 }
 121
 122 }  // namespace chrome_page_zoom