CODEWITHSUNDEEP
rggplot2shinyreactive
Dark Veaudor
Dark Veaudor

Reputation: 23

R Shiny multiple event reactive to build a ggplot

As an exercice to learn how to use R Shiny, I want to build a ggplot histogram with the values to be represented, fill, color and binwidth (choosable thanks to radioButton, selectInput and numericInput) working as reactive events : I want the plot to be generated when I click on the action button. There seems to be a problem with fill, color and binwidth during the graph generation.

Thank you very much for your help !

Here is my code

library(shiny)

ui <- fluidPage(
  
            box(
              title="Histogram ggplot", 
              status="primary", 
              solidHeader = TRUE,
              collapsible=TRUE,
              plotOutput("plot3", height = 250)),
            
            box(title="Bin",
                radioButtons("Bin1", "Nombre de Bins", c(100,500,700),100)),
            
            box(title="Fill",
                selectInput("Fill1", "Couleur de remplissage", c("white","blue"),"white")),
            
            box(title="Colour",
                selectInput("Color1", "Couleur de la bordure", c("black","blue"),"black" )),
            
            box(title="binwidth",
                numericInput("Binwidth1", "Binwidth", 0.3,0.1, 0.5, 0.005)),
            box(title='Bouton',
                actionButton("go3", "Show Graph"))
            
          )



server <- function(input, output) {
  valeur_random<-eventReactive(input$go3,{
    data.frame(a=rnorm(input$Bin1),b=rnorm(input$Bin1))
  })
  
  Fill2<-eventReactive(input$go3,{
    input$Fill1
  })
  
  Color2<-eventReactive(input$go3,{
    input$Color1
  })
  
  Binwidth2<-eventReactive(input$go3,{
    input$Binwidth1
  })  
  output$plot3 <- renderPlot({
    
    ggplot(data=valeur_random(), aes(a)) +
      geom_histogram(fill=Fill2,color=Color2,binwidth = Binwidth2)
    # when I replace this line with geom_histogram(fill="blue",color="white",binwidth = 0.1) it works !
  })
  
  }


shinyApp(ui, server)

Upvotes: 0

Views: 444

Answers (2)

Mohan Govindasamy
Mohan Govindasamy

Reputation: 906

Reactives are like any other function in shiny so you have to call it like a function for eg. data()

library(shiny)
library(tidyverse)

ui <- fluidPage(
    
   
        plotOutput("plot3", height = 250),
    
        radioButtons("Bin1", "Nombre de Bins", c(100,500,700),100),
    

        selectInput("Fill1", "Couleur de remplissage", c("white","blue"),"white"),
    

        selectInput("Color1", "Couleur de la bordure", c("black","blue"),"black" ),
    

        numericInput("Binwidth1", "Binwidth", 0.3,0.1, 0.5, 0.005),

        actionButton("go3", "Show Graph")
    
)



server <- function(input, output) {
    valeur_random<-eventReactive(input$go3,{
        data.frame(a=rnorm(input$Bin1),b=rnorm(input$Bin1))
    })
    
    Fill2<-eventReactive(input$go3,{
        input$Fill1
    })
    
    Color2<-eventReactive(input$go3,{
        input$Color1
    })
    
    Binwidth2<-eventReactive(input$go3,{
        input$Binwidth1
    })  
    output$plot3 <- renderPlot({
        
        ggplot(data=valeur_random(), aes(a)) +
             geom_histogram(fill=Fill2(),color=Color2(),binwidth = Binwidth2())
        # when I replace this line with geom_histogram(fill="blue",color="white",binwidth = 0.1) it works !
       
    
    })
    
}


shinyApp(ui, server)

But instead, you can call input variables directly instead of passing it in eventReactive

ggplot(data=valeur_random(), aes(a)) +
      geom_histogram(fill = input$Fill1, color = input$Color1, binwidth = input$Binwidth1)

Upvotes: 1

Ronak Shah
Ronak Shah

Reputation: 388982

Try using input$variable_name directly in geom_histogram.

library(shiny)
library(shinydashboard)
library(ggplot2)

ui <- fluidPage(
  
  box(
    title="Histogram ggplot", 
    status="primary", 
    solidHeader = TRUE,
    collapsible=TRUE,
    plotOutput("plot3", height = 250)),
  
  box(title="Bin",
      radioButtons("Bin1", "Nombre de Bins", c(100,500,700),100)),
  
  box(title="Fill",
      selectInput("Fill1", "Couleur de remplissage", c("white","blue"),"white")),
  
  box(title="Colour",
      selectInput("Color1", "Couleur de la bordure", c("black","blue"),"black" )),
  
  box(title="binwidth",
      numericInput("Binwidth1", "Binwidth", 0.3,0.1, 0.5, 0.005)),
  box(title='Bouton',
      actionButton("go3", "Show Graph"))
  
)

server <- function(input, output) {
  valeur_random<-eventReactive(input$go3,{
    data.frame(a=rnorm(input$Bin1),b=rnorm(input$Bin1))
  })
  
  output$plot3 <- renderPlot({
    ggplot(data=valeur_random(), aes(a)) +
      geom_histogram(fill = input$Fill1, color = input$Color1, binwidth = input$Binwidth1)
  })
  
}


shinyApp(ui, server)

Upvotes: 0

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