R ggplot barplot; Fill based on two separate variables

Question

A picture says more than a thousand words. As you can see, my fill is based on the variable variable.

Within each bar there is however mul

Answer 1

Adding alpha=complexity might work:

ggplot(short.m, aes(x=Method, y= value/100 , fill=variable, alpha=complexity)) +
geom_bar(stat="identity",position="dodge", colour="black") + coord_flip()