e_append1_p(proxy, series_index = NULL, data, x, y)

e_append1_p_(proxy, series_index = NULL, data, x, y)

e_append2_p(
  proxy,
  series_index = NULL,
  data,
  x,
  y,
  z,
  scale = NULL,
  symbol_size = 1
)

e_append2_p_(
  proxy,
  series_index = NULL,
  data,
  x,
  y,
  z,
  scale = NULL,
  symbol_size = 1
)

## Not run: 
library(shiny)

ui <- fluidPage(
  actionButton("add", "Add Data to y"),
  echarts4rOutput("plot"),
  h4("Brush"),
  verbatimTextOutput("selected"),
  h4("Legend select change"),
  verbatimTextOutput("legend")
)

server <- function(input, output, session) {
  data <- data.frame(x = rnorm(10, 5, 3), y = rnorm(10, 50, 12), z = rnorm(10, 5, 20))

  react <- eventReactive(input$add, {
    set.seed(sample(1:1000, 1))
    data.frame(x = rnorm(10, 5, 2), y = rnorm(10, 50, 10), z = rnorm(10, 5, 20))
  })

  output$plot <- renderEcharts4r({
    data %>%
      e_charts(x) %>%
      e_scatter(y, z, scale = NULL) %>%
      e_scatter(z) %>%
      e_brush()
  })

  observeEvent(input$add, {
    echarts4rProxy("plot") %>%
      e_append2_p(0, react(), x, y, z)
  })

  output$selected <- renderPrint({
    input$plot_brush
  })

  output$legend <- renderPrint({
    input$plot_legend_change
  })
}

shinyApp(ui, server)

## End(Not run)