base/prefs/scoped_user_pref_update.cc

   1 // Copyright 2013 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 "base/prefs/scoped_user_pref_update.h"
   6
   7 #include "base/logging.h"
   8 #include "base/prefs/pref_notifier.h"
   9 #include "base/prefs/pref_service.h"
  10
  11 namespace subtle {
  12
  13 ScopedUserPrefUpdateBase::ScopedUserPrefUpdateBase(PrefService* service,
  14                                                    const char* path)
  15     : service_(service),
  16       path_(path),
  17       value_(NULL) {
  18   DCHECK(service_->CalledOnValidThread());
  19 }
  20
  21 ScopedUserPrefUpdateBase::~ScopedUserPrefUpdateBase() {
  22   Notify();
  23 }
  24
  25 base::Value* ScopedUserPrefUpdateBase::GetValueOfType(base::Value::Type type) {
  26   DCHECK(CalledOnValidThread());
  27   if (!value_)
  28     value_ = service_->GetMutableUserPref(path_.c_str(), type);
  29   return value_;
  30 }
  31
  32 void ScopedUserPrefUpdateBase::Notify() {
  33   if (value_) {
  34     service_->ReportUserPrefChanged(path_);
  35     value_ = NULL;
  36   }
  37 }
  38
  39 }  // namespace subtle