Shiny Action Control Button Reactive Elements
Not sure if I should be using this term. Basically, I have a reactive function that displays a user-uploaded CSV file, and I would like to use it action button
to start the graph creation process. At this point, the plot is always generated on the fly. So I am wondering, in a function renderPlot
, how to let a action button
override an element reactive
. Thank!
ui.R
library(shiny)
shinyUI(fluidPage(
titlePanel("Test"),
sidebarLayout(
sidebarPanel(
fileInput('file1', 'Choose CSV File',
accept=c('text/csv',
'text/comma-separated-values,text/plain',
'.csv')),
checkboxGroupInput('show_vars', 'Columns to show:',
choices=c("Col1"="Col1", "Col2"="Col2", "Col3"="Col3"),
c("Col1"="Col1", "Col2"="Col2", "Col3"="Col3")),
uiOutput("study"),
actionButton("go", "Draw the plot")
),
mainPanel(
dataTableOutput('contents'),
plotOutput("Plot", width = 800, height = 800)
)
)
))
server.R
shinyServer(function(input, output) {
dataInput <- reactive({
inFile <- input$file1
if (is.null(inFile)) return(NULL)
data_load<-subset(read.csv(inFile$datapath, header=T, sep=",", quote='"', stringsAsFactors=FALSE), select=input$show_vars)
data_study<-unique(data_load$Col2)
return (list("data_load"=data_load, "data_study"=data_study))
})
study <- reactive({
all_citation<-dataInput()$data_load$Col2
study_choose<-unlist(lapply(input$columns, function(x) which(all_citation==x)))
return (list("study_choose"=study_choose))
})
##Generate the data table####
output$contents <- renderDataTable({
study_choose_temp<-study()$study_choose
dataInput()$data_load[study_choose_temp,]
})
###I would like the actionButton controls reactive elements
###dataInput()$data_load$Col3[study()$study_choose]
output$Plot <- renderPlot({
input$go
hist(dataInput()$data_load$Col3[study()$study_choose])
})
output$study <- renderUI({
# If missing input, return to avoid error later in function
if(is.null(dataInput()$data_study)) return()
# Create the checkboxes and select them all by default
checkboxGroupInput("columns", "Choose studies to plot",
choices = dataInput()$data_study,
selected = dataInput()$data_study)
})
})
source to share
Use isolate
in renderPlot()
so that it only updates when the button is pressed input$go
. If you do this, the graph will not redraw when other reactive elements change, but input$go
is outside isolate
, so it will redraw the graph.
output$Plot <- renderPlot({
input$go
isolate(
hist(dataInput()$data_load$Col3[study()$study_choose])
)
})
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