BarFormatter(android.content.Context ctx,
int xmlCfgId)
Provided as a convenience to users; allows instantiation and xml configuration
to take place in a single line
getRendererInstance(XYPlot plot)
Not completely sure why this is necessary, but if it's not here then
subclasses are forced to take a Plot instead of an XYPlot as a parameter,
which in turn breaks the pattern.
Not completely sure why this is necessary, but if it's not here then
subclasses are forced to take a Plot instead of an XYPlot as a parameter,
which in turn breaks the pattern.