feat: Add DisplayEventHandler class for handling display events with callbacks

Author: lijy91

examples/display_example/main.cpp

@@ -2,12 +2,22 @@
 #include "nativeapi.h"
 
 using nativeapi::Display;
-using nativeapi::Point;
+using nativeapi::DisplayEventHandler;
 using nativeapi::DisplayManager;
+using nativeapi::Point;
 
 int main() {
   DisplayManager displayManager = DisplayManager();
 
+  // DisplayEventHandler displayEventHandler = DisplayEventHandler(
+  //     [](const Display& display) {
+  //       std::cout << "Display added: " << display.id << std::endl;
+  //     },
+  //     [](const Display& display) {
+  //       std::cout << "Display removed: " << display.id << std::endl;
+  //     });
+  // displayManager.AddListener(&displayEventHandler);
+
   // Get primary display information
   Display primaryDisplay = displayManager.GetPrimary();
   std::cout << "Primary Display Information:" << std::endl;

src/display_manager.cpp

@@ -1,5 +1,3 @@
-#include <set>
-
 #include "display_manager.h"
 
 namespace nativeapi {
@@ -25,4 +23,22 @@ void DisplayManager::NotifyDisplayRemoved(const Display& display) {
   }
 }
 
+DisplayEventHandler::DisplayEventHandler(
+    std::function<void(const Display&)> onDisplayAddedCallback,
+    std::function<void(const Display&)> onDisplayRemovedCallback)
+    : onDisplayAddedCallback_(onDisplayAddedCallback),
+      onDisplayRemovedCallback_(onDisplayRemovedCallback) {}
+
+void DisplayEventHandler::OnDisplayAdded(const Display& display) {
+  if (onDisplayAddedCallback_) {
+    onDisplayAddedCallback_(display);
+  }
+}
+
+void DisplayEventHandler::OnDisplayRemoved(const Display& display) {
+  if (onDisplayRemovedCallback_) {
+    onDisplayRemovedCallback_(display);
+  }
+}
+
 }  // namespace nativeapi

src/display_manager.h

@@ -46,4 +46,24 @@ class DisplayManager {
   void NotifyDisplayRemoved(const Display& display);
 };
 
+// DisplayEventHandler is an implementation of DisplayListener that uses
+// callbacks to handle display events.
+class DisplayEventHandler : public DisplayListener {
+ public:
+  // Constructor that takes callbacks for display events
+  DisplayEventHandler(
+      std::function<void(const Display&)> onDisplayAddedCallback,
+      std::function<void(const Display&)> onDisplayRemovedCallback);
+
+  // Implementation of OnDisplayAdded from DisplayListener interface
+  void OnDisplayAdded(const Display& display) override;
+
+  // Implementation of OnDisplayRemoved from DisplayListener interface
+  void OnDisplayRemoved(const Display& display) override;
+
+ private:
+  std::function<void(const Display&)> onDisplayAddedCallback_;
+  std::function<void(const Display&)> onDisplayRemovedCallback_;
+};
+
 }  // namespace nativeapi