錯誤：視路徑必須包含至少一個視窗名

Question

Cross posted on Google groups of ggplot：下面的gglocator（GGPLOT2）重複的例子，

的：

library(ggplot2) 
library(ggmap) 
df <- data.frame(xvar = 1:10, yvar = 1:10) 
qplot(xvar, yvar, data = df) + annotate(geom = 'point', x = 3, y = 6) 
gglocator(4) 

作品上openSUSE 11.4 (64 bit)完美的罰款與sessionInfo()如下：

> sessionInfo() 
R version 2.15.1 (2012-06-22) 
Platform: x86_64-unknown-linux-gnu (64-bit) 

locale: 
[1] LC_CTYPE=en_US.UTF-8  LC_NUMERIC=C    
[3] LC_TIME=en_US.UTF-8  LC_COLLATE=en_US.UTF-8 
[5] LC_MONETARY=en_US.UTF-8 LC_MESSAGES=en_US.UTF-8 
[7] LC_PAPER=C     LC_NAME=C    
[9] LC_ADDRESS=C    LC_TELEPHONE=C   
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C  

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

other attached packages: 
[1] ggmap_2.1  ggplot2_0.9.1 

loaded via a namespace (and not attached): 
[1] colorspace_1.1-1 dichromat_1.2-4 digest_0.5.2  grid_2.15.1  
[5] labeling_0.1  MASS_7.3-18  memoise_0.1  munsell_0.3  
[9] plyr_1.7.1   png_0.1-4   proto_0.3-9.2  RColorBrewer_1.0-5 
[13] reshape2_1.2.1  RgoogleMaps_1.2.0 rjson_0.2.8  scales_0.2.1  
[17] stringr_0.6  

當在上運行時，相同的代碼會引發錯誤（標題中顯示）與sessionInfo()如下：

> sessionInfo() 
R version 2.15.1 (2012-06-22) 
Platform: i386-pc-mingw32/i386 (32-bit) 

locale: 
[1] LC_COLLATE=English_United States.1252 
[2] LC_CTYPE=English_United States.1252 
[3] LC_MONETARY=English_United States.1252 
[4] LC_NUMERIC=C       
[5] LC_TIME=English_United States.1252 

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

---

的ggplot2版本上Windows是0.9.2，並Linux是0.9.1。

這是一個已知的錯誤，還是我錯過了一個觀點？

Answer 1

我可以在Windows上重現問題。

其實在gglocator

x <- x[grep("panel-", grid.ls(print = message)[[1]])] 

grep的代碼沒有發現含有 '面板 - ' 任何GROB。

當我刪除了 -

x[grep("panel", grid.ls(print = message)[[1]])] 
[1] "panel.3-4-3-4"     "panel.background.rect.5210"  "panel.grid.minor.y.polyline.5212" "panel.grid.minor.x.polyline.5214" 
[5] "panel.grid.major.y.polyline.5216" "panel.grid.major.x.polyline.5218" "panel.border.zeroGrob.5207" 

對我來說，沒有任何理由，這在Linux上工作。