Add button and scrollbar element families

Author: v-rob

builtin/ui/elem_defs.lua

@@ -89,3 +89,5 @@ function ui.Grid:_encode_fields()
 
 	return ui._encode("ZS", ui.Elem._encode_fields(self), ui._encode_flags(fl))
 end
+
+ui.Button = ui._new_type(ui.Elem, "button", 0x04, true)

src/gui/elem.cpp

@@ -47,6 +47,7 @@ namespace ui
 			CREATE(ROOT, Root);
 			CREATE(FLEX, Flex);
 			CREATE(GRID, Grid);
+			CREATE(BUTTON, Button);
 		default:
 			return nullptr;
 		}

src/gui/elem.h

@@ -44,6 +44,7 @@ namespace ui
 			ROOT = 0x01,
 			FLEX = 0x02,
 			GRID = 0x03,
+			BUTTON = 0x04,
 		};
 
 	private:

src/gui/generic_elems.cpp

@@ -60,4 +60,14 @@ namespace ui
 
 		Elem::draw(canvas);
 	}
+
+	bool Button::processInput(const SDL_Event &event)
+	{
+		bool handled = Elem::processInput(event);
+		if (getMainBox().wasTriggered()) {
+			std::cout << "Triggered \"" << getId() << "\"" << std::endl;
+		}
+
+		return handled;
+	}
 }

src/gui/generic_elems.h

@@ -53,4 +53,16 @@ namespace ui
 
 		virtual void draw(Canvas &canvas);
 	};
+
+	class Button : public Elem
+	{
+	public:
+		Button(Window &window, std::string id) :
+			Elem(window, std::move(id), Box::DYNAMIC | Box::HOLDABLE | Box::USE_SPACE)
+		{}
+
+		virtual Type getType() const override { return BUTTON; }
+
+		virtual bool processInput(const SDL_Event &event) override;
+	};
 }