我不知道是否有一种方法可以独立于文本来控制图例颜色框的宽度(除了破解图例杂项之外).但是，如果在主题语句中添加legend.key.width=unit(1.5, "cm")，则所有颜色框都将扩展为相同的宽度(您可能需要向上或向下调整1.5来获得所需的框宽).

I don't know if there's a way to control the width of the legend color boxes separately from the text (other than hacking the legend grobs). However, if you add legend.key.width=unit(1.5, "cm") in your theme statement, all of the color boxes will be expanded to the same width (you may have to tweak the 1.5 up or down a bit to get the desired box widths).

library(scales)

ggplot(dataFrame, aes(x=color, y = percent))+
  geom_bar(aes(fill = cut), stat = "identity") +
  geom_text(aes(label = pretty_label), position=position_fill(vjust=0.5), 
            colour="white", size=3)+
  coord_flip()+
  theme(legend.position="top",
        legend.key.width=unit(1.5, "cm"))+
  guides(fill = guide_legend(label.position = "bottom", reverse = TRUE)) +
  scale_y_continuous(labels=percent)

您可以通过将Very Good放在两行上来节省一些空间:

You can save a little space by putting Very Good on two lines:

library(forcats)

ggplot(dataFrame, aes(x=color, y = percent, fill = fct_recode(cut, "Very\nGood"="Very Good")))+
  geom_bar(stat = "identity") +
  geom_text(aes(label = pretty_label), position=position_fill(vjust=0.5), 
            colour="white", size=3)+
  coord_flip()+
  theme(legend.position="top",
        legend.key.width=unit(1.2, "cm"))+
  guides(fill = guide_legend(label.position = "bottom", reverse = TRUE)) +
  labs(fill="Cut") +
  scale_y_continuous(labels=percent)