@Override
	public ListingField getField(ProxyObj<?> proxy, int varWidth) {
		if (!enabled) {
			return null;
		}
		if (proxy instanceof FunctionProxy) {
			FunctionProxy functionProxy = (FunctionProxy) proxy;
			Function function = functionProxy.getObject();
			SourceType source = function.getSignatureSource();
			String sourceStr = "<" + source.toString() + ">";
			AttributedString as =
				new AttributedString(sourceStr, FunctionColors.SOURCE, getMetrics());
			return ListingTextField.createSingleLineTextField(this, proxy,
				new TextFieldElement(as, 0, 0), startX + varWidth, width, hlProvider);
		}
		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