plot_annotation titles are removed when assembling or wrapping plots

[msto]

Hi,

I've found that titles added to a plot assembly are removed when trying to combine multiple assemblies into a larger figure.

I've extended the example in the assembly documentation page to demonstrate the issue. I'm able to add "Row1" and "Row2" to assemblies of the first and second plots and third and fourth plots, but these titles are removed when combining the assemblies with the stack operator (/) or wrap_plots().

I think this is a bug and not intended behavior, as using wrap_plots() with ncol=1 has the expected behavior of treating the sub-assemblies as individual plots, but please let me know if this is intended, or if I can add any other info.

Thanks!

library(ggplot2)
library(patchwork)

p1 <- ggplot(mtcars) + 
  geom_point(aes(mpg, disp)) + 
  ggtitle('Plot 1')

p2 <- ggplot(mtcars) + 
  geom_boxplot(aes(gear, disp, group = gear)) + 
  ggtitle('Plot 2')

p3 <- ggplot(mtcars) + 
  geom_point(aes(hp, wt, colour = mpg)) + 
  ggtitle('Plot 3')

p4 <- ggplot(mtcars) + 
  geom_bar(aes(gear)) + 
  facet_wrap(~cyl) + 
  ggtitle('Plot 4')

combo1 <- (p1 + p2) + plot_annotation("Row 1")
combo1

combo2 <- (p3 + p4) + plot_annotation("Row 2")
combo2

combo1 / combo2

wrap_plots(combo1, combo2, ncol=1)

[thomasp85]

This is a known limitation and is documented. At some point in the future I'll think about how to get around it

[msto]

Totally missed that note in the annotation docs, sorry. Thanks

[psychelzh]

Is there any workaround for this?

[abanihas]

@psychelzh @msto Same problem. Temporary solution in #145

[trizniak]

Is there any workaround for this?

I wrapped the plots in the list in patchwork::wrap_elements before the list goes into patchwork::wrap_plots