巧妙地识别子图( click_event )

Question

问题：假设一个巧妙的子图，其中包含多个情节。除了plotly_click和pointNumber之外，有没有一种方法可以通过curveNumber事件识别子图号？例如(例如，下面的代码)，p1得到指定的数字0，p2得到分配的数字1，p3得到分配的编号2，我可以使用与plotly_click事件类似的命令获得这些数字？

期望输出：

curveNumber pointNumber   x  y plotNumber
          4           1 Top 15         2

代码示例

library(shiny)
library(plotly)
library(data.table)

dt <- data.table(
  quarter = c("2020 Q1", "2020 Q1", "2019 Q4", "2019 Q4", "2019 Q3", "2019 Q3"),
  type = c("Hop", "Top", "Hop", "Top", "Hop", "Top"),
  count2 = c(3, 4, 5, 6, 0, 1),
  count = c(10, 20, 30, 40, 0, 15)
)

dt[, type := as.factor(type)]

ui <- fluidPage(
  mainPanel(
    plotlyOutput("plot")
  )
)

# Define server logic required to draw a histogram
server <- function(input, output) {

  output$plot <- renderPlotly({
    p1 <- plot_ly(dt[quarter == "2020 Q1"],
                  x = ~type,
                  y = ~count,
                  source = "plot_y") %>%
      add_bars(y = ~count) %>%
      add_bars(y = ~count2) %>%
      layout(barmode = "stack")

    p2 <- plot_ly(dt[quarter == "2019 Q4"],
                  x = ~type,
                  # y = ~count,
                  source = "plot_y")%>%
      add_bars(y = ~count) %>%
      add_bars(y = ~count2)%>%
      layout(barmode = "stack")

    p3 <- plot_ly(dt[quarter == "2019 Q3"],
                  x = ~type,
                  y = ~count,
                  source = "plot_y")%>%
      add_bars(y = ~count) %>%
      add_bars(y = ~count2)%>%
      layout(barmode = "stack")
list_p <- list(p1, p2, p3)
    subplot(list_p, shareY = TRUE)
  })

  observe({
    click <- event_data("plotly_click", source = "plot_y")
    req(click)
    print(click)
  })
}

# Run the application
shinyApp(ui = ui, server = server)

Answer 1

我认为您不能将类似plotNumber的内容添加到event_data中，但是可以使用customdata或key属性向event_data传递额外的信息。

下面是使用customdata更新的服务器功能

# Define server logic required to draw a histogram
server <- function(input, output) {

  output$plot <- renderPlotly({
    p1 <- plot_ly(dt[quarter == "2020 Q1"],
                  x = ~type,
                  y = ~count,
                  customdata='p1',
                  source = "plot_y") %>%
      add_bars(y = ~count) %>%
      add_bars(y = ~count2) %>%
      layout(barmode = "stack")

    p2 <- plot_ly(dt[quarter == "2019 Q4"],
                  x = ~type,
                  customdata='p2',
                  # y = ~count,
                  source = "plot_y")%>%
      add_bars(y = ~count) %>%
      add_bars(y = ~count2)%>%
      layout(barmode = "stack")

    p3 <- plot_ly(dt[quarter == "2019 Q3"],
                  x = ~type,
                  y = ~count,
                  customdata='p3',
                  source = "plot_y")%>%
      add_bars(y = ~count) %>%
      add_bars(y = ~count2)%>%
      layout(barmode = "stack")
    list_p <- list(p1, p2, p3)
    subplot(list_p, shareY = TRUE)
  })

  observe({
    click <- event_data("plotly_click", source = "plot_y")
    req(click)
    print(click)
  })
}

输出：

  curveNumber pointNumber   x  y customdata
1           4           1 Top 15         p3