[BioC] Question about subtracks shown using ‘rtracklayer’ package

[LiGang]

Dear list,

I have one question about subtracks shown using ‘rtracklayer’ package. Using
‘rtracklayer’ package, we can easily show any tracks on some particular genomic
region, however, when one track contains several subtracks (for example, for
hg18 assembly, the ‘HAIB Methyl-seq’ contain 29 subtracks, but the default
settings only show 6 of the total 29 subtracks). 

So my question is how to change the ‘HAIB Methyl-seq Track Settings’ using some
functions in ‘rtracklayer’package to let this track show all the 29 subtracks.
Thanks!


LiGang