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recharts4r

How to change area style with echarts4r::e_area()

I can change the line style and the item style, but I cannot seem to be able to pass arguments to areaStyle (see areaStyle).

For example:

library(echarts4r)
data.frame(x = seq.int(1, 5, 1),
           y = 10) %>% 
  e_chart(x = x) %>% 
  e_area(
    serie = y,
    areaStyle = list(opacity = 0),
    lineStyle = list(opacity = 0),
    itemStyle = list(opacity = 0)
  )

produces an area chart with no points and no line, but the area is still visible. How do I change the color, opacity, etc. of the area itself?

Solution

  • I had a look at the source code of e_area_ (which is called by e_area). and the issue is that e_area_ inits areaStyle as an empty list. See https://github.com/JohnCoene/echarts4r/blob/bf23891749cf42a40656fa87ff04ecb3627a9af5/R/add_.R#L263-L269 . And unfortunately this empty list doesn't gets updated when the user provides his own specs. Not sure whether this is a bug or whether this is intended. Perhaps you should file an issue.

    As a possible quick workaround here is "fixed" e_area2_ which updates the default empty list via modifyList:

    library(echarts4r)
library(dplyr)

e_area2_ <- function(e, serie, bind = NULL, name = NULL, legend = TRUE,
                     y_index = 0, x_index = 0, coord_system = "cartesian2d", ...) {
  .default <- list(areaStyle = list())

  args <- utils::modifyList(.default, list(...))

  if (missing(e)) {
    stop("must pass e", call. = FALSE)
  }
  if (missing(serie)) {
    stop("must pass serie", call. = FALSE)
  }
  for (i in seq_along(e$x$data)) {
    vector <- echarts4r:::.build_data2(
      e$x$data[[i]], e$x$mapping$x,
      serie
    )
    if (!is.null(bind)) {
      vector <- echarts4r:::.add_bind2(e, vector, bind, i = i)
    }
    l <- list(data = vector)
    if (coord_system == "cartesian2d") {
      if (y_index != 0) {
        e <- echarts4r:::.set_y_axis(e, serie, y_index, i)
      }
      if (x_index != 0) {
        e <- echarts4r:::.set_x_axis(e, x_index, i)
      }
      l$yAxisIndex <- y_index
      l$xAxisIndex <- x_index
    } else if (coord_system == "polar") {
      l$data <- as.list(unname(unlist(dplyr::select(
        e$x$data[[i]],
        serie
      ))))
    }
    if (!e$x$tl) {
      nm <- echarts4r:::.name_it(e, serie, name, i)
      args
      opts <- c(
        list(name = nm, type = "line", coordinateSystem = coord_system),
        args
      )

      l <- append(l, opts)
      if (isTRUE(legend)) {
        e$x$opts$legend$data <- append(
          e$x$opts$legend$data,
          list(nm)
        )
      }
      e$x$opts$series <- append(e$x$opts$series, list(l))
    } else {
      e$x$opts$options[[i]]$series <- append(
        e$x$opts$options[[i]]$series,
        list(l)
      )
    }
  }
  if (isTRUE(e$x$tl)) {
    if (is.null(name)) {
      name <- serie
    }
    series_opts <- c(
      list(
        name = name, type = "line", yAxisIndex = y_index,
        xAxisIndex = x_index, coordinateSystem = coord_system
      ),
      args
    )
    if (isTRUE(legend)) {
      e$x$opts$baseOption$legend$data <- append(
        e$x$opts$baseOption$legend$data,
        list(name)
      )
    }
    e$x$opts$baseOption$series <- append(
      e$x$opts$baseOption$series,
      list(series_opts)
    )
  }
  e
}

data.frame(
  x = seq.int(1, 5, 1),
  y = 10
) %>%
  e_chart(x = x) %>%
  e_area2_(
    serie = "y",
    areaStyle = list(opacity = 0),
    lineStyle = list(opacity = 0),
    itemStyle = list(opacity = 0)
  )