Class CloseButton

src/app/TipWindow.cpp:152–157

		buttonLayout->addChild(nextButton);

		struct CloseButton : ui::Button {
			TipWindow* tipWindow;
			void onAction(const ActionEvent& e) override {
				tipWindow->getParent()->requestDelete();
			}
		};
		CloseButton* closeButton = new CloseButton;
		closeButton->box.size.x = buttonWidth;
		closeButton->text = "✖  " + string::translate("TipWindow.close");