I am learning the Shiny interface for R and working through the first example.
The histogram changes based on the slider input. How do I have it update continuously, while the slider is moving? Right now, it only updates when the slider stops moving.
ui.R
library(shiny)
# Define UI for application that draws a histogram
shinyUI(fluidPage(
# Application title
titlePanel("Hello Shiny!"),
# Sidebar with a slider input for the number of bins
sidebarLayout(
sidebarPanel(
sliderInput("bins",
"Number of bins:",
min = 1,
max = 50,
value = 30)
),
# Show a plot of the generated distribution
mainPanel(
plotOutput("distPlot")
)
)
))
server.R
library(shiny)
# Define server logic required to draw a histogram
shinyServer(function(input, output) {
# Expression that generates a histogram. The expression is
# wrapped in a call to renderPlot to indicate that:
#
# 1) It is "reactive" and therefore should re-execute automatically
# when inputs change
# 2) Its output type is a plot
output$distPlot <- renderPlot({
x <- faithful[, 2] # Old Faithful Geyser data
bins <- seq(min(x), max(x), length.out = input$bins + 1)
# draw the histogram with the specified number of bins
hist(x, breaks = bins, col = 'darkgray', border = 'white')
})
})
What I have tried:
#server.R
library(shiny)
shinyServer(function(input,output) {
x<-faithful[,2]
bins <- reactive({
seq(min(x),max(x),length.out=input$bins+1)
})
output$distPlot <- renderPlot({
hist(x,breaks=bins(),col='darkgray',border='white')})
})
Is there a way to make it react faster/real-time?
Thanks to Dean's response I investigated the shinyCustom package in github.
Here is my solution:
#Shiny UI
library(shiny)
library(shinyCustom)
# Define UI for application that draws a histogram
shinyUI(fluidPage(
# Application title
titlePanel("Hello Shiny!"),
# Sidebar with a slider input for the number of bins
sidebarLayout(
sidebarPanel(
useShinyCustom(slider_delay = "0"), #make a call to shinyCustom, where there is no delay
customSliderInput("bins", #Use customSliderInput instead of sliderInput
"Number of bins:",
min = 1,
max = 50,
value = 30)
),
# Show a plot of the generated distribution
mainPanel(
plotOutput("distPlot")
)
)
))
App now updates as you move the slider
Related
I am developing a Shiny app. It works fine, but when I am refreshing the browser it is in, the app seemingly returns to its initial stage. How can I prevent it so that whenever I refresh I also remain in my present page?
To replicate the problem I am attaching the following example of a shiny app. How can I refresh it while preserving the last value I set it on?
library(shiny)
ui <- fluidPage(
# App title ----
titlePanel("Hello Shiny!"),
# Sidebar layout with input and output definitions ----
sidebarLayout(
# Sidebar panel for inputs ----
sidebarPanel(
# Input: Slider for the number of bins ----
sliderInput(inputId = "bins",
label = "Number of bins:",
min = 1,
max = 50,
value = 30)
),
# Main panel for displaying outputs ----
mainPanel(
# Output: Histogram ----
plotOutput(outputId = "distPlot")
)
)
)
server <- function(input, output) {
# Histogram of the Old Faithful Geyser Data ----
# with requested number of bins
# This expression that generates a histogram is wrapped in a call
# to renderPlot to indicate that:
#
# 1. It is "reactive" and therefore should be automatically
# re-executed when inputs (input$bins) change
# 2. Its output type is a plot
output$distPlot <- renderPlot({
x <- faithful$waiting
bins <- seq(min(x), max(x), length.out = input$bins + 1)
hist(x, breaks = bins, col = "#75AADB", border = "white",
xlab = "Waiting time to next eruption (in mins)",
main = "Histogram of waiting times")
})
}
shinyApp(ui, server)
I have some plots which are displayed once the submit button is clicked but before that, the tab remains clean. I want some text to be displayed there so that the user can see something before hitting the submit button and once when the button is clicked, I want the text to be removed and it must display the plots.
Here is my take on the example shiny app:
library(shiny)
library(shinyjs)
# Define UI for application that draws a histogram
ui <- fluidPage(
useShinyjs(),
# Application title
titlePanel("Old Faithful Geyser Data"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
sliderInput("bins",
"Number of bins:",
min = 1,
max = 50,
value = 30),
actionButton("submit", "Show plot")
),
# Show a plot of the generated distribution
mainPanel(
tabsetPanel(
tabPanel(
"Plot",
uiOutput("help_text"),
plotOutput("distPlot")
)
)
)
)
)
# Define server logic required to draw a histogram
server <- function(input, output) {
output$help_text <- renderUI({
HTML("<b>Click 'Show plot' to show the plot.</b>")
})
plot_data <- eventReactive(input$submit, {
hide("help_text")
# generate bins based on input$bins from ui.R
x <- faithful[, 2]
bins <- seq(min(x), max(x), length.out = input$bins + 1)
# draw the histogram with the specified number of bins
hist(x, breaks = bins, col = 'darkgray', border = 'white')
})
output$distPlot <- renderPlot({
plot_data()
})
}
# Run the application
shinyApp(ui = ui, server = server)
I have a shiny app with a longer computation depending on the input. I am wondering if it is possible to display a text in the main panel at the same time when the computation is done (and not before).
Let's make an easy example. I simulated the longer computation with Sys.sleep():
# Define UI for application that draws a histogram
ui <- shinyUI(fluidPage(
# Application title
titlePanel("Old Faithful Geyser Data"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
sliderInput("bins",
"Number of bins:",
min = 1,
max = 50,
value = 30)
),
# Show a plot of the generated distribution
mainPanel(
h3('This is an example'),
plotOutput("distPlot")
)
)
))
# Define server logic required to draw a histogram
server <- shinyServer(function(input, output) {
output$distPlot <- renderPlot({
# generate bins based on input$bins from ui.R
x <- faithful[, 2]
bins <- seq(min(x), max(x), length.out = input$bins + 1)
# draw the histogram with the specified number of bins
hist(x, breaks = bins, col = 'darkgray', border = 'white')
Sys.sleep(5)
})
})
# Run the application
shinyApp(ui = ui, server = server)
The goal would be, to show the text 'This is an example' at the same time the computation is done and not before.
I think I have to make the text somehow reactive, but so far I haven't found a solution for this. Maybe a conditionalPanel could do it, but how can I bring the computation time in the condition? Any ideas?
Would this be what you search for? Your text variable as a reactive after observing the event of distPlot
library(shiny)
# Define UI for application that draws a histogram
ui <- shinyUI(fluidPage(
# Application title
titlePanel("Old Faithful Geyser Data"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
sliderInput("bins",
"Number of bins:",
min = 1,
max = 50,
value = 30)
),
# Show a plot of the generated distribution
mainPanel(
textOutput('text1'),
plotOutput("distPlot")
)
)
))
# Define server logic required to draw a histogram
server <- shinyServer(function(input, output) {
output$distPlot <- renderPlot({
# generate bins based on input$bins from ui.R
x <- faithful[, 2]
bins <- seq(min(x), max(x), length.out = input$bins + 1)
# draw the histogram with the specified number of bins
hist(x, breaks = bins, col = 'darkgray', border = 'white')
Sys.sleep(2)
})
observeEvent(plotOutput("distPlot"), {
output$text1 <- renderText({ paste("Number of bins:", input$bins)})
})
})
# Run the application
shinyApp(ui = ui, server = server)
Is there a way to get italic words in my shiny titlePanel?
I tried
library(shiny)
# Define UI for application that draws a histogram
ui <- shinyUI(fluidPage(
# Application title
titlePanel("Old <em>Faithful Geyser</em> Data"),
# Sidebar with a slider input for number of bins
sidebarLayout(
sidebarPanel(
sliderInput("bins",
"Number of bins:",
min = 1,
max = 50,
value = 30)
),
# Show a plot of the generated distribution
mainPanel(
plotOutput("distPlot")
)
)
))
# Define server logic required to draw a histogram
server <- shinyServer(function(input, output) {
output$distPlot <- renderPlot({
# generate bins based on input$bins from ui.R
x <- faithful[, 2]
bins <- seq(min(x), max(x), length.out = input$bins + 1)
# draw the histogram with the specified number of bins
hist(x, breaks = bins, col = 'darkgray', border = 'white')
})
})
# Run the application
shinyApp(ui = ui, server = server)
and this print the title as Old <em>Faithful Geyser</em> Data. The em does not get interpreted. Am I doing something wrong or isn't there a way to get italic font in the title?
hello try this it should work
titlePanel( div(HTML("Old <em>Faithful Geyser</em> Data")))
This is my ui.R. This is an example provided in Shiny tutorial. I just edited it.
library(shiny)
library(markdown)
# Define UI for application that draws a histogram
shinyUI(fluidPage(
# Application title
titlePanel("Hello Shiny!"),
# Sidebar with a slider input for the number of bins
sidebarLayout(
sidebarPanel(
sliderInput("bins",
"Number of bins:",
min = 1,
max = 50,
value = 30)
),
# Show a plot of the generated distribution
mainPanel(
plotOutput("distPlot"),
absolutePanel(
bottom = 0, left=420, width = 800,
draggable = TRUE,
wellPanel(
em("This panel can be moved")
)
)
))
))
and my server. R
library(shiny)
# Define server logic required to draw a histogram
shinyServer(function(input, output) {
# Expression that generates a histogram. The expression is
# wrapped in a call to renderPlot to indicate that:
#
# 1) It is "reactive" and therefore should be automatically
# re-executed when inputs change
# 2) Its output type is a plot
output$distPlot <- renderPlot({
x <- faithful[, 2] # Old Faithful Geyser data
bins <- seq(min(x), max(x), length.out = input$bins + 1)
# draw the histogram with the specified number of bins
hist(x, breaks = bins, col = 'darkgray', border = 'white')
})
})**
In this case, sliderInput is not working. If i remove absolute panel, sliderInput is ok. What may be the problem? Many thanks
The absolutePanel uses the jqueryui javascript library. It has its own slider. This results in a conflict with sliderInput which uses jslider library. You can see this as follows:
library(shiny)
runApp(
list(ui = fluidPage(
titlePanel("Hello Shiny!"),
sidebarLayout(
sidebarPanel(
sliderInput("bins",
"Number of bins:",
min = 1,
max = 50,
value = 30)
),
mainPanel(
plotOutput("distPlot")
, tags$head(tags$script(src = "shared/jqueryui/1.10.3/jquery-ui.min.js"))
)
)
),
server = function(input, output) {
output$distPlot <- renderPlot({
x <- faithful[, 2] # Old Faithful Geyser data
bins <- seq(min(x), max(x), length.out = input$bins + 1)
hist(x, breaks = bins, col = 'darkgray', border = 'white')
})
}
)
)
EDIT: This has been fixed in the latest dev version of shiny. The slider component has been removed from the jqueryui inc. https://github.com/rstudio/shiny/commit/7e12a281f51e047336ba2c501fcac43af5253225