@Override
	public void programSelectionChanged(ProgramSelection selection, EventTrigger trigger) {
		if (trigger != EventTrigger.GUI_ACTION) {
			return;
		}
		// We need to translate the given selection (which is from a single vertex) to the current
		// overall selection for the graph (which includes the selection from all vertices).  We
		// do this so that a selection change in one vertex does not clear the selection in
		// other vertices
		FunctionGraph graph = functionGraphData.getFunctionGraph();
		ProgramSelection fullSelection = graph.getProgramSelectionForAllVertices();

		// push the user changes up to the provider
		viewSettings.setSelection(fullSelection);
		provider.graphSelectionChanged(fullSelection);
	}
Sets the message that will appear in the lower part of the graph.

@param message the message to display
Ghidra/Features/FunctionGraph/src/main/java/ghidra/app/plugin/core/functiongraph/mvc/FGController.java