public void layoutFields() {
		width = 0;
		for (int i = 0; i < fields.size(); i++) {
			FieldFactory factory = fields.get(i);
			factory.setStartX(width);
			width += factory.getWidth();
		}
	}
Notifies that the field options have changed.
@param options the Options object that changed.
@param optionName the name of the property that changed.
@param oldValue the old value of the property.
@param newValue the new value of the property.
Ghidra/Features/Base/src/main/java/ghidra/app/util/viewer/format/FieldFormatModel.java