Adding persistance for gesture recognition parms.

chrome/browser/gesture_prefs.cc

+// Copyright (c) 2012 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.
+
+#include "chrome/browser/gesture_prefs.h"
+
+#include "base/memory/singleton.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/prefs/pref_service.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/pref_names.h"
+#include "ui/aura/gestures/gesture_configuration.h"
+
+namespace {
+
+#if defined(USE_AURA)

[rjkroege, 2012/02/24 15:21:34]

From my experience, this pattern is atypical. I would expect that it is
preferable to have a gesture_prefs.h, gesture_prefs_aura.h and
gesture_prefs_aura.cc with the second two included only in the aura built by gyp
configuration.

+// This class manages gesture configuration preferences.
+class GesturePrefs : public content::NotificationObserver {
+ public:
+  static GesturePrefs *GetInstance();
+  void RegisterPrefs(PrefService* prefs);
+
+ private:
+  GesturePrefs();
+  friend struct DefaultSingletonTraits<GesturePrefs>;
+  virtual ~GesturePrefs();
+
+  // content::NotificationObserver implementation.
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+ private:
+  void Update();
+
+  PrefChangeRegistrar registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(GesturePrefs);
+};
+
+GesturePrefs::GesturePrefs() {
+}
+
+GesturePrefs::~GesturePrefs() {
+}
+
+GesturePrefs* GesturePrefs::GetInstance() {
+  return Singleton<GesturePrefs>::get();
+}
+
+// The list of prefs we want to observe.

[rjkroege, 2012/02/24 15:21:34]

this would need to be updated for changes to the GR? Can you make a note here
noting the requirement to keep this in alignment with actual GR parameters.

+const char* kPrefsToObserve[] = {
+  prefs::kMaximumTouchDownDurationInSecondsForClick,
+  prefs::kMinimumTouchDownDurationInSecondsForClick,
+  prefs::kMaximumSecondsBetweenDoubleClick,
+  prefs::kMaximumTouchMoveInPixelsForClick,
+  prefs::kMinFlickSpeedSquared,
+};
+
+const int kPrefsToObserveLength = arraysize(kPrefsToObserve);
+
+void GesturePrefs::RegisterPrefs(PrefService* ) {

[rjkroege, 2012/02/24 15:21:34]

how will the webui adjust the constants? Am I right to think that it should get
a local_state object and then call local_state->SetDouble('key', num)

+  PrefService* local_state = g_browser_process->local_state();
+
+  local_state->RegisterDoublePref(
+    prefs::kMaximumTouchDownDurationInSecondsForClick, 0.8);
+  local_state->RegisterDoublePref(
+    prefs::kMinimumTouchDownDurationInSecondsForClick, 0.01);
+  local_state->RegisterDoublePref(
+    prefs::kMaximumSecondsBetweenDoubleClick, 0.7);
+  local_state->RegisterDoublePref(
+    prefs::kMaximumTouchMoveInPixelsForClick, 20);
+  local_state->RegisterDoublePref(
+    prefs::kMinFlickSpeedSquared, 550.f*550.f);
+
+  registrar_.Init(local_state);
+  if (local_state) {
+    for (int i = 0; i < kPrefsToObserveLength; ++i)
+      registrar_.Add(kPrefsToObserve[i], this);
+  }
+}
+
+void GesturePrefs::Update() {
+  PrefService* local_state = g_browser_process->local_state();
+
+  aura::GestureConfiguration::set_max_touch_down_duration_in_seconds_for_click(
+    local_state->GetDouble(prefs::kMaximumTouchDownDurationInSecondsForClick));
+  aura::GestureConfiguration::set_min_touch_down_duration_in_seconds_for_click(
+    local_state->GetDouble(prefs::kMinimumTouchDownDurationInSecondsForClick));
+  aura::GestureConfiguration::set_max_seconds_between_double_click(
+    local_state->GetDouble(prefs::kMaximumSecondsBetweenDoubleClick));
+  aura::GestureConfiguration::set_max_touch_move_in_pixels_for_click(
+    local_state->GetDouble(prefs::kMaximumTouchMoveInPixelsForClick));
+  aura::GestureConfiguration::set_min_flick_speed_squared(
+    local_state->GetDouble(prefs::kMinFlickSpeedSquared));
+}
+
+void GesturePrefs::Observe(int type,
+                           const content::NotificationSource& source,
+                           const content::NotificationDetails& details) {
+  Update();
+}
+#endif
+
+}  // namespace
+
+
+// static
+void GesturePrefsHelper::RegisterPrefs(PrefService* prefs) {
+#if defined(USE_AURA)
+  GesturePrefs::GetInstance()->RegisterPrefs(prefs);
+#endif
+}