@Override
	public ProgramLocation getProgramLocation(int row, int col, ListingField bf) {
		ProxyObj<?> proxy = bf.getProxy();
		if (proxy instanceof FunctionProxy) {
			FunctionProxy functionProxy = (FunctionProxy) proxy;
			Function function = functionProxy.getObject();
			return new FunctionSignatureSourceFieldLocation(function.getProgram(),
				functionProxy.getLocationAddress(), functionProxy.getFunctionAddress(),
				function.getSignatureSource().toString(), col);
		}

		return null;
	}
Constructor
@param model the model that the field belongs to.
@param hlProvider the HightLightProvider.
@param displayOptions the Options for display properties.
@param fieldOptions the Options for field specific properties.
Ghidra/Features/Base/src/main/java/ghidra/app/util/viewer/field/FunctionSignatureSourceFieldFactory.java