Method onAction

src/MidiThing.cpp:641–645

	struct MidiDeviceChoice : LedDisplayCenterChoiceEx {
		midi::Port* outPort, *inPort;
		void onAction(const event::Action& e) override {
			if (!outPort || !inPort)
				return;
			createContextMenu();
		}

		virtual ui::Menu* createContextMenu() {
			ui::Menu* menu = createMenu();