echarts4r, shiny, dynamic multiplot

Question

I would like to generate dynamic multiplots in R with shiny and echarts4r. I expect 3 different charts, but get 3 times the same chart and i don't get why. If I plot them non dynamically, I get the expectet plots.

rm(list=ls())

library(shiny)

library(echarts4r)

#library(pryr)

data1=1:3
data2=rep(0,3)
data = data.frame(data1,data2)

ui <- fluidPage(
  headerPanel("MultiPlot"),
  mainPanel(
    
    uiOutput("main"),
    actionButton("start","Start")
  )
)

plotdata = function(listeX){
  liste = listeX[[1]]
  data = listeX[[2]]
  
  while(any(data$data2==0))
  {
    pos_0 = which(data$data2==0)[1]
    data$data2[pos_0]=1
    data_plot=data[pos_0,]
    liste[[length(liste)+1]] = renderEcharts4r({
    
      data_plot %>%
        e_charts(data1)  %>%
        e_line(data2) %>% 
        e_tooltip("axis","item")  %>% 
        e_title(paste0("Chart",pos_0))
    })
    listeX = list(liste,data)
    plotdata(listeX)
  }
  return(listeX)
}

server <- function(input, output,session) {

  observeEvent(input$start,{
    output$main  = renderUI({
      liste = list(  
        tags$br()
      )
      
      listeX = list(liste,data)
      listeX = plotdata(listeX)
      liste = listeX[[1]]
      tagList(
        liste
      )
    })
    
  })
}

shinyApp(ui = ui, server = server)

I have tried recursive code as well as iterative code, but i get 3 times the last generated plot each time

Answer 1

I have solved my problem. First I created all the echarts4rOutputs and after that I plot iterativ for every row. Here the working code:

    library(shiny)
    
    library(echarts4r)
    
    data1=1:3
    data2=1:3
    data_all = data.frame(data1,data2)
    
    
    ui <- fluidPage(
      headerPanel("MultiPlot"),
      
      mainPanel(
        actionButton("start","Start"),
        uiOutput("plotMain"),
      )
    )
    plotdata = function(data){
      data_plot = data
      
      plotx <- renderEcharts4r({
        data_plot %>%
          e_charts(data1)  %>%
          e_line(data2) %>% 
          e_tooltip("axis","item")  %>% 
          e_title(paste0("Chart",data_plot$data1))
        # e_mark_line(data = list(yAxis=y_min),title="UT",col="red") %>%
        # e_mark_line(data = list(yAxis=y_max),title="OT")
        
      })
      return(plotx)
      
    }
    
    server <- function(input, output,session) {
      
      output$plotMain = renderUI({
        
        liste = list()
        for(i in 1:nrow(data_all))
        {
          liste[[(length(liste)+1)]] = echarts4rOutput(paste0("plot",i))
        }
        liste
        
      })
      
      observeEvent(input$start,{
        
        for(i in 1:nrow(data_all))
        {
          plotx = plotdata(data_all[i,])
          output[[paste0("plot",i)]] = plotx
        }
      })
    }
    
    shinyApp(ui = ui, server = server)