Hi I-Hsuan,

there is some basic information on how to do that on the IdeogramTrack help page, im particular under the 'bands' argument section:

? IdeogramTrack

  bands: A ‘data.frame’ with the cytoband information for all

          available chromosomes on the genome similar to the data that

          would be fetched from UCSC. The table needs to contain the

          mandatory columns ‘chrom’, ‘chromStart’, ‘chromEnd’, ‘name’

          and ‘gieStain’ with the chromosome name, cytoband start and

          end coordinates, cytoband name and coloring information,

          respectively. This can be used when no connection to the

          internet is available or when the cytoband information has

          been cached locally to avoid the somewhat slow connection to

          UCSC.

So assuming that you have created the necessary IdeogramTrack data.frame, you could initialize the object like this

idTrack <- IdeogramTrack(genome="yourGenomeName", bands=yourBandsDataFrame)

Now where you get the bands information from is totally up to you. In the easiest case you would just use the chromosome lengths for the chromStart and chromEnd values, essentially creating Ideograms without banding.

Florian