不知道怎么更改阴影类型？
还有显示red ambar green 各种占比

rm(list = ls())

setwd("d:/Agriculture/")

install.packages("readstata13")

library(readstata13)

gtayear <- read.dta13("gtayear1.dta")

names(gtayear) <- c("startyear", "gtaeval", "numgta")

gtayear$gtaeval1 <- factor(gtayear$gtaeval)

library(ggplot2)

p <- ggplot(gtayear, aes(startyear))

p + geom_bar()

p + geom_bar(aes(fill = gtaeval), position = "dodge") + ggtitle("The Change of The GTA over the year") +
  labs(x = "Year", y = "The Measure of GTA")

gtayeargtaeval1<−factor(gtayear,gtaeval)

谢谢！

想让每年三个分类显示不同的阴影类型，怎么做？使用theme()?具体怎么做？谢谢