Using the input from updateSelectInput - r

Question

My problem is when selecting data using the input from "updateSelectInput".
input$State and input$Company returns no values to my "data selection" function, input$Transport that is not an "update" works fine.
How I call an input when using "updateSelectInput"? Does it work in the same way as "selectInput"?
Thanks in advance!
Here is the data I created to simplify the problem:
Company<- paste('company',1:95)
State<- paste('state',1:20)
Transport<-c('inter long','nacional long','nacional short','inter short')
variable1<- sample(0:10,380,replace=T)
variable2<- sample(0:10,380,replace=T)
variable3<- sample(0:10,380,replace=T)
variable4<- sample(0:10,380,replace=T)
mydata<- data.frame(Company,State,Transport,variable1,variable2,variable3,variable4)
ui.R
shinyUI(pageWithSidebar(
headerPanel('Passengers Data'),
sidebarPanel(
selectInput("Transport", "Select a Transport", choices = levels(mydata$Transport), selected = levels(mydata$Transport)[1]
),
selectInput("State", "Select a State", choices = sort(levels(mydata$State)),selected = sort(levels(mydata$State)[1])),
tags$hr(),
checkboxGroupInput("Company", "Select Company", choices = mydata$Company[mydata$State ==sort(mydata$State )[1] & mydata$Transport==sort(mydata$Transport)[1]]),
width = 3
),
mainPanel(
htmlOutput("plot1"),width = 9
)
))
server.R
library(ggplot2)
library(googleVis)
shinyServer(function(input, output, session) {
observe({
Transport2<- input$Transport
updateSelectInput(session, "State", choices = sort(levels(factor(mydata$State[mydata$Transport == Transport2]))),selected = sort(levels(factor(mydata$State[mydata$Transport == Transport2])))[1])
})
observe({
Transport2<- input$Transport
State2 <- input$State
updateCheckboxGroupInput(session, "Company", choices = sort(levels(factor(mydata$Company[mydata$State == State2 & mydata$Transport == Transport2]))),selected=sort(levels(factor(mydata$Company[mydata$State == State2 & mydata$Transport == Transport2])))[1:5])
})
selectedData<-reactive({
subset(mydata, mydata$Transport==input$Transport & mydata$State==input$State & mydata$Company==input$Company
)
})
output$plot1 <- renderGvis({
gvisBarChart(selectedData(), xvar="Company", yvar="variable1",
options=list(legend='none', width=750, height=425,title="Resultado geral",
titleTextStyle="{color:'black',fontName:'Courier',fontSize:16}",
bar="{groupWidth:'70%'}"))
})
})

Answer 1

First, there's a bug in this line:
subset(mydata, mydata$Transport==input$Transport & mydata$State==input$State & mydata$Company==input$Company
Specifically the last clause:
mydata$Company==input$Company
should be replaced with
mydata$Company %in% input$Company
since input$Company can have multiple values.
Also, the selected values you're passing to updateSelectInput are sometimes c(NA, NA, NA, NA, NA) which Shiny doesn't understand (it causes a JavaScript error in the browser). You should call na.omit on the selection before you give it to updateSelectInput. (If this makes things even worse, install the latest version of RJSONIO from CRAN--it used to have a bug with empty vectors in lists.)
Thirdly, I'd recommend adding this code to the top of your renderGvis expression:
validate(
need(nrow(selectedData()) > 0, "No data")
)
It will make it easier to detect when there are no rows in your data (rather than a blank graph which could be the result of an error or something).