use pattern 'Observer' final

kudryashovda · Nov 3, 2021 · 8857428 · 8857428
1 parent e518edb
commit 8857428
Showing 1 changed file with 34 additions and 27 deletions.
diff --git a/WeatherData/weatherdata.cpp b/WeatherData/weatherdata.cpp
@@ -8,14 +8,18 @@ using std::vector;
 
 class Observer {
 public:
-    virtual void update(float temp, float humidity, float pressure) = 0;
+    virtual void update() = 0;
 };
 
 class Subject {
 public:
     virtual void registerObserver(Observer* observer) = 0;
     virtual void removeObserver(Observer* observer) = 0;
     virtual void notifyObservers() = 0;
+
+    [[nodiscard]] virtual float getTemperature() const = 0;
+    [[nodiscard]] virtual float getHumidity() const = 0;
+    [[nodiscard]] virtual float getPressure() const = 0;
 };
 
 class DisplayElement {
@@ -34,10 +38,9 @@ class CurrentConditionsDisplay : public Observer, DisplayElement {
         cout << "Current conditions: " << temperature_ << " C degrees and " << humidity_ << "% humidity" << '\n';
     }
 
-    void update(float temp, float humidity, float pressure) override {
-        temperature_ = temp;
-        humidity_ = humidity;
-        (void)pressure;
+    void update() override {
+        temperature_ = weatherData_->getTemperature();
+        humidity_ = weatherData_->getHumidity();
         display();
     }
 
@@ -59,21 +62,20 @@ class StatisticsDisplay : public Observer, DisplayElement {
         cout << "Avg/Max/Min: " << average_temp_ << '/' << max_temp_ << '/' << min_temp_ << '\n';
     }
 
-    void update(float temp, float humidity, float pressure) override {
-        temperature_ = temp;
-        humidity_ = humidity;
-        pressure_ = pressure;
-        temps_.push_back(temp);
-        if (temp > max_temp_) {
-            max_temp_ = temp;
+    void update() override {
+        float temperature_ = weatherData_->getTemperature();
+
+        temps_.push_back(temperature_);
+        if (temperature_ > max_temp_) {
+            max_temp_ = temperature_;
         }
 
-        if (temp < min_temp_) {
-            min_temp_ = temp;
+        if (temperature_ < min_temp_) {
+            min_temp_ = temperature_;
         }
         float sum_temp = 0.0;
-        for (float temperature: temps_) {
-            sum_temp += temperature;
+        for (float temp : temps_) {
+            sum_temp += temp;
         }
         if (!temps_.empty()) {
             average_temp_ = sum_temp / temps_.size();
@@ -85,10 +87,6 @@ class StatisticsDisplay : public Observer, DisplayElement {
 private:
     Subject* weatherData_;
 
-    float temperature_ = 0.0;
-    float humidity_ = 0.0;
-    float pressure_ = 0.0;
-
     float min_temp_ = 273;
     float max_temp_ = -273;
     float average_temp_ = 0.0;
@@ -106,17 +104,14 @@ class ForecastDisplay : public Observer, DisplayElement {
         cout << "Tomorrow will be a good day (50%)" << '\n';
     }
 
-    void update(float temp, float humidity, float pressure) override {
-        (void)temp;
-        (void)humidity;
-        pressure_ = pressure;
+    void update() override {
+        pressures_.push_back(weatherData_->getPressure());
         display();
     }
 
 private:
     Subject* weatherData_;
-
-    float pressure_ = 0.0;
+    vector<float> pressures_;
 };
 
 class WeatherData : public Subject {
@@ -129,7 +124,7 @@ class WeatherData : public Subject {
     }
     void notifyObservers() override {
         for (auto* observer : observers_) {
-            observer->update(temperature_, humidity_, pressure_);
+            observer->update();
         }
     }
 
@@ -145,6 +140,18 @@ class WeatherData : public Subject {
         measurementsChanged();
     }
 
+    [[nodiscard]] float getTemperature() const override {
+        return temperature_;
+    }
+
+    [[nodiscard]] float getHumidity() const override {
+        return humidity_;
+    }
+
+    [[nodiscard]] float getPressure() const override {
+        return pressure_;
+    }
+
 private:
     set<Observer*> observers_;
     float temperature_ = 0.0;