问题

数据有些多，原图不好复现，但是原因有：

plot_grid(xy_z_plot, xy_z_plot, labels = c("A", "B"), align = "v",nrow = 2)

> warnings()
警告信息：
...
12: In grid.Call(C_textBounds, as.graphicsAnnot(x$label),  ... :
  'mbcsToSbcs'里转换'姘翠綅/m'出错：<8d>代替了dot
13: In grid.Call(C_textBounds, as.graphicsAnnot(x$label),  ... :
  'mbcsToSbcs'里转换'涓嬫父闃叉椽鏍囧噯搴撴按浣嶅彉鍖栧浘'出错：<e4>代替了dot
14: In grid.Call(C_textBounds, as.graphicsAnnot(x$label),  ... :

我查了下，发现有同学在rmd中使用ggplot2时出现了这个问题，通过谢大的一个方法解决了，但是我尝试不成功……

另外

warnings出现后再画任何图的时候RStudio右下图框再也显示不出来图了，只能restart and reload workspace……
有的说可能是字体的问题，我也把代码贴这里吧！一切问题都是在运行最上面那个代码的时候出现的。
我移除了所有汉字，warnings()没有出现了，但是图依旧没有，1中的情况仍然没变……

xy_io_plot <- ipl_xy %>% gather(inout,q,c(2,4))%>%
ggplot(aes(x = n,y = q,color = as.factor(inout),lty = as.factor(inout)))+
  theme_bw()+
  ggalt::geom_xspline(size = 1.5) + 
  theme(plot.subtitle = element_text(vjust = 1), 
    plot.caption = element_text(vjust = 1), 
    plot.title = element_text(hjust = 0.5),legend.title = element_blank(),
    legend.justification = c(1,1),legend.position = c(0.99,0.99)) +
  labs(title = "下游防洪标准水库调洪示意图", 
    x = "时间/h", y = expression(流量/(m^3/s)))+
  scale_linetype_manual(values = c(1,5),
                        breaks = c("q_in","q_out"),
                        labels = c("入库流量","下泄流量"))+
  scale_color_manual(values = c("red2","cyan"),
                        breaks = c("q_in","q_out"),
                        labels = c("入库流量","下泄流量"))

xy_z_plot <- ggplot(ipl_xy,aes(x = n,y = z))+
  theme_bw()+
  ggalt::geom_xspline(size = 1.2,color = "lightpink") + 
  theme(plot.subtitle = element_text(vjust = 1), 
    plot.caption = element_text(vjust = 1), 
    plot.title = element_text(hjust = 0.5)) +
  labs(title = "下游防洪标准库水位变化图", x = "时间/t", 
    y = "水位/m")
    
plot_grid(xy_z_plot, xy_z_plot, labels = c("A", "B"), align = "v",nrow = 2)

系统信息

> sessionInfo()
R version 3.5.3 (2019-03-11)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows >= 8 x64 (build 9200)

Matrix products: default

locale:
[1] LC_COLLATE=Chinese (Simplified)_China.936  LC_CTYPE=Chinese (Simplified)_China.936   
[3] LC_MONETARY=Chinese (Simplified)_China.936 LC_NUMERIC=C                              
[5] LC_TIME=Chinese (Simplified)_China.936    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] shiny_1.3.0       cowplot_0.9.4     ourbir_0.1.0      forcats_0.4.0     stringr_1.4.0     dplyr_0.8.0.1    
 [7] purrr_0.3.2       readr_1.3.1       tidyr_0.8.3       tibble_2.1.1      ggplot2_3.1.1     tidyverse_1.2.1  
[13] data.table_1.12.0 multicolor_0.1.2  lubridate_1.7.4   praise_1.0.0      pacman_0.5.1     

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.1          lattice_0.20-38     assertthat_0.2.1    digest_0.6.18       proj4_1.0-8        
 [6] mime_0.6            R6_2.4.0            cellranger_1.1.0    plyr_1.8.4          backports_1.1.3    
[11] httr_1.4.0          pillar_1.3.1        Rmisc_1.5           rlang_0.3.4         lazyeval_0.2.2     
[16] readxl_1.3.1        rstudioapi_0.10     miniUI_0.1.1.1      extrafontdb_1.0     labeling_0.3       
[21] extrafont_0.17      ggalt_0.4.0         munsell_0.5.0       broom_0.5.1         httpuv_1.5.1       
[26] compiler_3.5.2      modelr_0.1.3        pkgconfig_2.0.2     htmltools_0.3.6     tidyselect_0.2.5   
[31] later_0.8.0         crayon_1.3.4        withr_2.1.2         MASS_7.3-51.1       grid_3.5.2         
[36] xtable_1.8-3        nlme_3.1-137        jsonlite_1.6        Rttf2pt1_1.3.7      gtable_0.3.0       
[41] magrittr_1.5        formatR_1.6         scales_1.0.0        ggThemeAssist_0.1.5 KernSmooth_2.23-15 
[46] cli_1.1.0           stringi_1.4.3       promises_1.0.1      xml2_1.2.0          generics_0.0.2     
[51] ash_1.0-15          RColorBrewer_1.1-2  Cairo_1.5-9         tools_3.5.2         glue_1.3.1         
[56] maps_3.3.0          hms_0.4.2           yaml_2.2.0          colorspace_1.4-1    rvest_0.3.2        
[61] haven_2.1.0