在R. ggplot中删除轴和绘图之间的空间，scale_x_continuous（expand = c（0,0））不工作

Question

我正在使用ggplot2在R中创建一个图表。在绘图下方和x轴上方有空间我想要删除。

基于此问题How to remove space between axis & area-plot in ggplot2?我尝试将expand = c(0,0)添加到scale_x_continuous()中，但这似乎无法解决问题。

我认为有一个简单的解决方案，我不知何故。先感谢您。

我的代码：

     q_cbb <- ggplot(cbb.sum, aes(year, CBB.Incidence, fill=category)) +
       geom_vline(xintercept = seq(2008.5,2011.5), color="gray") + 
       geom_hline(yintercept = seq(10,70,10), color="gray") + 
       geom_bar(stat="identity", position="dodge") +
       geom_errorbar(aes(ymin=CBB.Incidence-se, ymax=CBB.Incidence+se), width=0.2, position=position_dodge(.9)) +
       scale_x_continuous(limits=c(2007.5,2012.5), expand=c(0,0))+xlab("Year")+ylab("Mean Incidence (%)") + 
       ggtitle("CBB Incidence, Local vs All Other Var.") +
       scale_fill_discrete(name = "Type", labels=c("All Other Vars.", "Local", "CBB resistant")) + 
       theme(plot.title = element_text(hjust = 0.5)) + 
       theme(panel.grid.major = element_blank(), panel.grid.minor = element_blank()) + 
       ylim(0,70) +
       theme(axis.line = element_line(colour = "black"))

    q_cbb

最后，这是我的数据：

    category year   N CBB.Incidence       sd       se        ci
1      local 2008  21     23.023810 31.60221 6.896168 14.385155
2      local 2009  34      8.823529 19.40136 3.327306  6.769454
3      local 2010  39     14.530769 22.94635 3.674356  7.438345
4      local 2011  42     61.026190 31.16832 4.809376  9.712731
5      local 2012  21     37.928571 39.22975 8.560633 17.857167
6      other 2008 105     22.603810 30.12916 2.940305  5.830736
7      other 2009  81     13.583951 19.65220 2.183578  4.345459
8      other 2010 130     37.864615 34.44426 3.020962  5.977046
9      other 2011  91     45.787912 38.36813 4.022073  7.990550
10     other 2012  84     25.309524 31.10835 3.394199  6.750926
12 resistant 2008 256     39.829687 37.42764 2.339227  4.606665
13 resistant 2009 238     22.633613 28.69892 1.860275  3.664786
14 resistant 2010 467     32.500214 32.15739 1.488067  2.924152
15 resistant 2011 464     48.953233 40.72924 1.890808  3.715628
16 resistant 2012 441     22.929478 27.36686 1.303184  2.561239