Combining all the word sources

Case Studies: Building Web Applications with Shiny in R

Dean Attali

Shiny Consultant

Combining all the word sources

3 data sources for word cloud
- Text object: artofwar
- User text: textAreaInput()
- Text file: fileInput()
Next step: allow all together
- Radio buttons to select word source

Radio buttons - review

radioButtons(
    "time_of_day", "Choose your favorite time of day",
    choices = c("Morning", "Afternoon", "Evening"),
    selected = "Afternoon"
)

Radio buttons - advanced

radioButtons(
    "time_of_day", "Choose your favorite time of day",
    choices = c("I'm a morning person!" = "Morning",
                "Love my afternoons"    = "Afternoon",
                "Night owl here!"       = "Evening"),
    selected = "Afternoon"
)

str(input$time_of_day)

chr "Afternoon"

Conditional panels

Show/hide UI elements based on input value

conditionalPanel(condition, ...)

condition is similar to R code, but input$<id> is replaced by input.<id>
... is any UI

Conditional panels

ui <- fluidPage(
  radioButtons("time_of_day",
               "Choose your favorite time of day",
               ...),

  plotOutput("morning_only_plot")
)

ui <- fluidPage(
  radioButtons("time_of_day",
               "Choose your favorite time of day",
               ...),

  conditionalPanel(
    condition = "input.time_of_day == 'Morning'",
    plotOutput("morning_only_plot")
  )
)

Let's practice!

Case Studies: Building Web Applications with Shiny in R