e_highlight_p(proxy, series_index = NULL, series_name = NULL)

e_downplay_p(proxy, series_index = NULL, series_name = NULL)

## Not run: 
library(shiny)

ui <- fluidPage(
  fluidRow(
    column(
      3,
      actionButton("highlightmpg", "Highlight MPG")
    ),
    column(
      3,
      actionButton("highlighthp", "Highlight HP")
    ),
    column(
      3,
      actionButton("downplaympg", "Downplay MPG")
    ),
    column(
      3,
      actionButton("downplayhp", "Downplay HP")
    )
  ),
  echarts4rOutput("plot")
)

server <- function(input, output, session) {
  output$plot <- renderEcharts4r({
    mtcars %>%
      e_charts(mpg) %>%
      e_line(disp) %>%
      e_line(hp, name = "HP") # explicitly pass name
  })

  # highlight

  observeEvent(input$highlightmpg, {
    echarts4rProxy("plot") %>%
      e_highlight_p(series_index = 0) # using index
  })

  observeEvent(input$highlighthp, {
    echarts4rProxy("plot") %>%
      e_highlight_p(series_name = "HP") # using name
  })

  # downplay

  observeEvent(input$downplaympg, {
    echarts4rProxy("plot") %>%
      e_downplay_p(series_name = "disp")
  })

  observeEvent(input$downplayhp, {
    echarts4rProxy("plot") %>%
      e_downplay_p(series_index = 1)
  })
}

if (interactive()) {
  shinyApp(ui, server)
}

## End(Not run)