switch to using own event system

src/ui/BuildButtonGrid.h

@@ -5,28 +5,30 @@
 
 #include <QWidget>
 
+#include "BuilderModeExitedEvent.h"
 #include "BuildingType.h"
+#include "DemolishModeChangedEvent.h"
+#include "EventHandler.h"
 #include "GameConfig.h"
 
 class QPushButton;
 
-class BuildButtonGrid : public QWidget
+class BuildButtonGrid : public QWidget,
+                        public CombinedEventHandler<BuilderModeExitedEvent,
+                                                    DemolishModeChangedEvent>
 {
     Q_OBJECT
 
 public:
     BuildButtonGrid(const GameConfig* config, QWidget* parent = nullptr);
+    ~BuildButtonGrid() override;
 
     void updateAffordability(int buildingBlocks);
     void clearActiveButton();
 
-signals:
-    void buildingTypeSelected(BuildingType type);
-    void builderModeExited();
-    void demolishModeToggleRequested();
-
-public slots:
-    void setDemolishModeActive(bool active);
+private:
+    void handleEvent(std::shared_ptr<const BuilderModeExitedEvent> event) override;
+    void handleEvent(std::shared_ptr<const DemolishModeChangedEvent> event) override;
 
 private slots:
     void onBuildButton(int index);