r - store arrangeGrob to object, does not create printable object -

i want save, not print (for now), bunch of ggplot()s grid (via arrangegrob(), correct?), print , retrieve them later.

this reboot of existing question. strangely, that answer not work, , have no idea why. using exact same code.

  library(ggplot2)   p1 <- ggplot(mtcars, aes(x=factor(cyl), y=mpg)) + geom_boxplot()   p2 <- ggplot(mtcars, aes(x=factor(cyl), y=wt)) + geom_boxplot()   library(gridextra)   y <- arrangegrob(p1, p2)   class(y)   y 

strangely, not (as in above answer) yield grid of plots, but:

> class(y) [1] "gtable" "grob"   "gdesc"  > y tablegrob (2 x 1) "arrange": 2 grobs   z     cells    name           grob 1 1 (1-1,1-1) arrange gtable[layout] 2 2 (2-2,1-1) arrange gtable[layout] 

what going on here?

the gridextra package has been updated thereby changing how arrangegrob works internally , kind of object returns (now gtable).

you need call grid.draw:

grid.draw(y) 

edit: not use plot() suggested; add grey background, , meant used debugging gtables.