private void handleFVEvent(FVEvent event) {

		switch (event.eventType) {

			case VIEWPORT_UP:
				moveViewportUp((int) event.arg, false);
				break;
			case VIEWPORT_DOWN:
				moveViewportDown((int) event.arg, false);
				break;
			case VIEWPORT_PAGE_UP:
				moveViewportUp(getNumRowsInViewport(), (boolean)event.arg);
				break;
			case VIEWPORT_PAGE_DOWN:
				moveViewportDown(getNumRowsInViewport(), (boolean)event.arg);
				break;
			default:
		}
	}
Processes events received via the {@link FVEvent} mechanism. 

@param event the event type received
Ghidra/Framework/Project/src/main/java/ghidra/framework/main/logviewer/ui/ViewportUtility.java