如何将链接嵌入到likert图中，为每个likert项单独链接

Question

我试图使用likert包和gridSVG包的组合，将超链接嵌入到likert数据图中。我想把每个问题的文本链接到一个单独的链接上，但是我遇到了一些问题。下面的代码嵌入到每个问题的文本的单个链接，但我无法找到如何分别嵌入每个问题，因为这组问题似乎被分组在一个单一的grob中。提前感谢您的投入。

#creates an example plot from sample data from likert package.
require(likert) 
data(pisaitems)
items29 <- pisaitems[,substr(names(pisaitems), 1,5) ==  "ST25Q" ]
names(items29) <- c("Magazines", "Comic books", "Fiction",
               "Non-fiction books", "Newspapers")
l29 <- likert(items29)
summary(l29)
plot(l29)

require(grid)
require(gridSVG)

#identifies grob of question text (all questions are in a single grob)
titleGrobName <- grep("axis-l.3-3-3-3", grid.ls(print=FALSE)$name, value=TRUE)

#embeds link in grob
grid.hyperlink(titleGrobName, "http://www.r-project.org")

#creates svg
gridToSVG("testPlot.svg", "none", "none")

Answer 1

这种分组GROB并不少见。因为我认为我们不想重写likert来取消对它们的分组，所以我们最好用XML在grid之后操作SVG。这里有一种方法可以实现这一点。

实例化

我们也可以添加在HTML/JavaScript方面的链接，如果你期望这张图形是一个更大的网页的一部分。

#creates an example plot from sample data from likert package.
require(likert) 
data(pisaitems)
items29 <- pisaitems[,substr(names(pisaitems), 1,5) ==  "ST25Q" ]
names(items29) <- c("Magazines", "Comic books", "Fiction",
                    "Non-fiction books", "Newspapers")
l29 <- likert(items29)
summary(l29)
plot(l29)

# if possible to use htmltools from RStudio
#   install.packages("htmltools")
#  then we can add the links on the
#  XML side instead of in grid
library(XML)
library(htmltools)
library(gridSVG)

# export as XML SVG
likert_svg <- grid.export("", addClasses=TRUE)$svg

# find our axes
nodes <- getNodeSet(
  likert_svg,
  # thanks http://stackoverflow.com/questions/5818681/xpath-how-to-select-node-with-some-attribute-by-index
  "(//x:g[contains(@id,'axis')])[1]//x:tspan",
  "x"
)

lapply(
  nodes,
  function(node){
    # get the text value of the node
    lbl = xmlValue(node)
    # remove the text from our node
    xmlValue(node) <- ""

    # create a <a href=> hyperlink
    #  https://www.w3.org/wiki/SVG_Links
    a_node <- newXMLNode(
      "a",
      #######   change your link here ###########
      attrs = c("xlink:href"=paste0("http://google.com/search?q=",lbl)),
      lbl
    )
    # add our new linked text to the node
    addChildren(node, a_node)
  }
)


# look at it in the browser/RStudio Viewer
browsable(
  HTML(
    saveXML(
      #  export as SVG XML
      likert_svg,
      prefix = ""
    )
  )
)