Frequently Asked Questions

Question: I opened my older feature model and all the nodes and connections are messed up. What happened?
What is the problem: This is caused by version incompatibility between XFeature 0.9.8 ald older and XFeature 2.0.0 and above.
Solution: Delete the *.pos file associated with your feature model. If your feature model is MyProject/MyFeatureModel/FamilyModel42.xfm then your *.pos file is named MyProject/MyFeatureModel/FamilyModel42.pos. If you do not see the *.pos file try to refresh the folder where the *.pos file is supposed to be.

Question: I do not understand the validation error message.
Answer: We use XML Schema to validate the feature model. Sometimes the error message is hard to understand. If all attempts to understand where the problem is fails we follow the line number reported by XML Schema validator. We open the feature model in XML editor or text editor and look at the line where the problem is reported. If the line is too long, try to pretty print the XML file, save it, re-open the feature model, and validate it again. This always worked for us.

Question: What's wrong with space characters? Why the error messages?
Answer: From version 2.1.0 we no more support space characters. We have had a lot of issues with spaces on the paths. The XML parser sometimes have problem to locate the meta-model (which is W3C XML Schema document) location. Also calling the XMLValidation task from Ant is cumbersome and error prone. Between late 2005 and mid 2007 we were dealing with 8 bug reports caused by space character issues and we decided to put an end to this.

Question: I opened a feature model and got this error message: "The meta-model file (as defined in the *.xfm file) doesn't exist. The invalid path is: {some path}"
What should I do?
What is the problem: The path to the meta-model is bound to the feature model. If the meta-model is deleted from the place where it was when the feature model was edited last time you will get this error when trying to reopen the file.
Solution: Open the feature model with text editor and search it for string xsi:schemaLocation="http://www.pnp-software.com/XFeature/fmm
What follows this string is the path to the last know location of the meta-model. Replace it with the current position of the meta-model

Question: I want to know what is going on when XFeature generates the application meta-model or global constraints. Where to look?
Answer: First, all the temporary files are generated to folder which is specified in the xfproject.xpr file in element TmpLoc. By default is is tmp subfolder of the folder where is the xfproject.xpr file itself. Second, uncheck the "Make Ant output concise (quiet mode)" option in the XFeature preferences (menu Window | Preferences... | XFeature).

Question: Why cannot I add second feature under the root feature?
Answer: First, it is important realize that what can be added where is defined in the meta-model. Hence, the general answer is "Consult your meta-model". If your meta-model happens to be FD.xfmm or ICSR.xfmm than the answer is "You cannot because the meta-model defines that the feature model has exactly one top feature (with optional subfeatures) and any number of macros. The top feature and macros are child nodes of the root node". Search your XFeature installation folder for SimpleControlSystem.xfm file to see an example where the top feature SpacecraftControlSystem has multiple subfeatures and one sibling macro.

Question: How can I remove property ?
Answer: We haven't implemented it (yet). Remove the whole property set -- right-click the node with the property, select "Remove property set", and choose the one with the property that you want to get rid of.

Question: How can I add comments to a feature?
Answer: Right-click the feature and choose New node/cardinality/set | Annotation. Then right-click the feature again and choose New property with PropertySet | Annotation (1) | Add Comment in Annotation (1). At this point you should see the Comment entry in the properties view. If you do not see the properties view, right-click the feature once again and choose Show Properties View.

Question: How can I add the tooltips?
Answer: Use the same sequence of actions as for comments (see right above). Just instead of "Comment" choose "ShortDescription". The tooltip always displays the content of the ShortDescription property.

Question: What is the number in brackets that I can see in some property sets e.g. Attribute (2)?
Answer: XFeature is highly configurable tool. As such it allows you to define more property sets of the same name as children of one feature. The numbers are used solely for the purpose of distinguishing the property sets ... even in cases where there happen to be only one property set.

Question: I want to specify the data type for my attribute. What are the supported data types?
Answer: Again this is entirely dependent on the configuration of the XFeature that you use. If you use the FD or ICSR configuration than use the XML Schema data types with "xs" prefix. For example: xs:string, xs:integer, xs:float, xs:double, xs:boolean...

Question: Hey, Cut & Paste doesn't work!
Answer: It does. You probably cut a node, then pasted it elsewhere, and now you are surprised that it is back at the position where it was before the cut. It looks like the cut node is back, but in reality it is now child node of the other parent (just as you wanted). Check the outline view! You can also move the new parent and see that the pasted node (or its connections) move accordingly. We simply let the feature model layout entirely in hands of users. Let us know if you find bug in cut & paste, please.

Question: I have different question. How can I get the fastest answer?
Answer: Write to rohlik@pnp-software.com.