1 /* 2 * Copyright (c) 2021 Huawei Device Co., Ltd. 3 * Licensed under the Apache License, Version 2.0 (the "License"); 4 * you may not use this file except in compliance with the License. 5 * You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software 10 * distributed under the License is distributed on an "AS IS" BASIS, 11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 * See the License for the specific language governing permissions and 13 * limitations under the License. 14 */ 15 16 #include "observer.h" 17 18 using namespace std; 19 20 namespace OHOS { 21 AddObserver(const shared_ptr<Observer> & o)22 void Observable::AddObserver(const shared_ptr<Observer>& o) 23 { 24 if (o == nullptr) { 25 return; 26 } 27 28 lock_guard<mutex> lock(mutex_); 29 if (obs.count(o) > 0) { 30 return; 31 } 32 33 obs.insert(o); 34 } 35 RemoveObserver(const shared_ptr<Observer> & o)36 void Observable::RemoveObserver(const shared_ptr<Observer>& o) 37 { 38 lock_guard<mutex> lock(mutex_); 39 obs.erase(o); 40 } 41 RemoveAllObservers()42 void Observable::RemoveAllObservers() 43 { 44 lock_guard<mutex> lock(mutex_); 45 obs.clear(); 46 } 47 HasChanged()48 bool Observable::HasChanged() 49 { 50 return changed_; 51 } 52 GetObserversCount()53 int Observable::GetObserversCount() 54 { 55 lock_guard<mutex> lock(mutex_); 56 return (int)obs.size(); 57 } 58 NotifyObservers()59 void Observable::NotifyObservers() 60 { 61 NotifyObservers(nullptr); 62 } 63 NotifyObservers(const ObserverArg * arg)64 void Observable::NotifyObservers(const ObserverArg* arg) 65 { 66 set<shared_ptr<Observer>> arrLocal; 67 { 68 lock_guard<mutex> lock(mutex_); 69 if (!changed_) { 70 return; 71 } 72 73 arrLocal = obs; 74 ClearChanged(); 75 } 76 77 for (auto& o : arrLocal) { 78 o->Update(this, arg); 79 } 80 } 81 SetChanged()82 void Observable::SetChanged() 83 { 84 changed_ = true; 85 } 86 ClearChanged()87 void Observable::ClearChanged() 88 { 89 changed_ = false; 90 } 91 92 } 93