[cdt-dev] Programmatically excluding files from build - not saved

[Christian Walther <walther@xxxxxxxx>]

I take the lack of response to my previous question as confirmation  
that nobody knows of a better way to achieve my goal and excluding  
files from build is the way to go. So, on to my next question that I  
already alluded to in passing:

I'm trying to programmatically set the "exclude from build" setting of  
a file in a CDT project, i.e. modify the source folders and exclusion  
patterns of the active configuration. I have found two ways of doing  
that:

	bool exclude = true;
	IManagedBuildInfo buildInfo =  
ManagedBuildManager.getBuildInfo(project);
	IConfiguration activeConfig = buildInfo.getDefaultConfiguration();
	ICSourceEntry[] sourceEntries = activeConfig.getSourceEntries();
	Path newPath = new Path("my/test/file.cpp");
	sourceEntries = CDataUtil.setExcluded(newPath, false, exclude,  
sourceEntries);
	activeConfig.setSourceEntries(sourceEntries);

or

	bool exclude = true;
	IFile file = project.getFile("my/test/file.cpp");
	IResourceConfiguration ResConfig =  
activeConfig.createResourceConfiguration(file);
	ResConfig.setExclude(exclude);

Both achieve the desired modification in "Properties > C/C++ Build" on  
the file and "Properties > C/C++ General > Paths and Symbols > Source  
Location" on the project, however the change is neither saved to  
the .cproject file immediately nor does it appear to be scheduled for  
future saving - when I close the project at this point and reopen it,  
the change is lost. Only when I manually make another change to the  
project (opening the Properties dialog on any file and clicking OK  
seems to be sufficient), the exclusion is properly saved.

What do I have to do in addition to the code above to make the change  
persistent?

I have tried setting the "dirty" flags that exist on various involved  
objects (activeConfig, buildInfo, buildInfo.getManagedProject()) but  
that didn't help (IIRC most were already set anyway).

I have also noticed that during the Scanner Configuration Builder (my  
code runs in a custom builder before that), code is executed that  
serializes the project to XML, and that serialization does contain my  
modification, but apparently doesn't end up in the .cproject file (I  
have not followed its complicated paths any further).

 -Christian