Nsryjdtyk

I've added a date filter to my Shiny App. Now I want to filter the data frame dynamically according to the date input.

I tried this as follows in ui.R:

fluidPage(

      selectInput(

        "analysis_period",

        "analysie period:",

        c(

          "Last Year" = "LY",

          "Past 90 days" = "ND",

          "Past 30 days" = "TD",

          "Last Week" = "LW"

        )

      )

     )

In my server section I have:

date_input <- reactive({

if (input$analysis_period== "NT") {

  as.Date(Sys.time()) - 90

}



else if (input$analysis_periodm == "DT") {

  as.Date(Sys.time()) - 30

}



else if (input$analysis_periodum == "LW") {

  as.Date(Sys.time()) - 7

}



else if (input$analysis_period == "LY") {

  m = as.POSIXlt(as.Date(Sys.time()))

  m$year = m$year - 1

  m

}

})

Then I want to load the data frame and filter it using the filter:

data2 = data[, c('A', 'B', 'C')]

data2 <- filter(data2, date_input())

But when I start the app I always get the error:

Error in filter_impl(.data, quo) : 

Evaluation error: Operation not allowed without an active reactive context. 

(You tried to do something that can only be done from inside a reactive 

expression or observer.).

What am I doing wrong here?

Ok I got it. When I executed the reactive inside a reactive expression or observer it works. Thank you guys for your help.

I did it like this:

  output$x1 <- DT::renderDataTable({

df <- data2

df<- filter(df, df$date >= dateinput())

df

})

You have to use date_input in a reactive function, but if necessary you can get value outside by using isolate().

But the goal of reactive function in Shiny it's to use isolate() at the minimum.

I don't know if your data2 = data[, c('A', 'B', 'C')] is outside a reactive function.

links:

• https://shiny.rstudio.com/articles/isolation.html


• https://shiny.rstudio.com/reference/shiny/1.0.1/isolate.html