Shiny App to Test User Input Forms (Using actionButtons)

projects.csv

server.R

library(shiny)
library(shinyIncubator)
library(plyr)

# load a very small projects file
# Eventually the idea is to have a database link to SQLite or access
projects=read.csv("projects.csv",sep=",",stringsAsFactors=FALSE)

# Define server logic 
shinyServer(function(input, output) {
  
  # if Projects -> View Projects is selected, this outputs the lists in dataframe projects
  output$projlist=reactivePrint(function(){
    
      if(!(input$menuproj == "View Projects")) return(NULL)
      
      df=ddply(projects,c("project"),subset,updttime == max(updttime))
      df2=df[order(df$project),]   
      
    })
  
  # if Projects -> Add New Project is selected and
  # a new project is entered in the text box and
  # Add new project button is clicked
  
  # projnew is the variable that is set to 1 when a project is added and reset to 0 
  # immediately after that. This ensures that subsequent typing in text box doesn't have any impact
  # unless the add new project button is clicked again
  projnew <<- 0
  addproj=reactive(function(){
    input$projnew
    if(input$projnew > 0) {projnew <<- 1}
  })
  
  output$newprojout=reactivePrint(function(){
  
     # call to reactive function that responds to clicking add new project button
     addproj()
     
     # Message when button is not clicked
     if(projnew == 0) {
       # I am not sure why the following line is needed here but somehow had problems without this line
        input$projnew 
        msg="Click Add New Project Button to Submit Project"
        return(msg)
     }
    
     # adding the new project to database when button is clicked
     pidnew=nrow(projects)+1
     updttime=as.character(Sys.time())
     projects <<- rbind(projects,data.frame(
     pid=pidnew,
     project=input$newproj,
     duedt=input$newduedt,
     stage=input$newstg,
     updttime=updttime
               ))
    
     # resetting projnew to 0 so that any typing in text box has no impact
     projnew <<- 0     
     
     # output
     projects[nrow(projects),]
     
        })
  
  output$projnames=reactiveUI(function(){
    
      if(input$menuproj == "Modify Existing Project") {
            projname=unique(projects$project)
            selectInput("modifproj","Modify Project",
                        choices=c("ChooseOne",projname))
                      }
      })

  # projmodif is the variable that is set to 1 when a project is modified and reset to 0 
  # immediately after that. This ensures that subsequent typing in text box doesn't have any impact
  # unless button is clicked again
  projmodif <<- 0
  modifproj=reactive(function(){
    input$projmodif
    if(input$projmodif > 0) {projmodif <<- 1}
  })
  
  
  output$modifprojout=reactivePrint(function(){
    
    # call to reactive function that responds to clicking modify project button
    modifproj()
    
    # Message when button is not clicked
    if(projmodif == 0) {
      # I am not sure why the following line is needed here but somehow had problems without this line
      input$projmodif 
      msg="Click Modify Project Button to Modify Project"
      return(msg)
    }
    
    # adding modified project data to the database
    pidnew=nrow(projects)+1
    updttime=as.character(Sys.time())
    projects <<- rbind(projects,data.frame(
    pid=pidnew,
    project=input$modifproj,
    duedt=input$modifduedt,
    stage=input$modifstg,
    updttime=updttime
        ))

    projsub=projects[projects$project == input$modifproj,]
    
    # resetting projnew to 0 so that any typing in text box has no impact
    projmodif <<- 0
    
    #output
    projsub[nrow(projsub),]
      
    
  })
  
})

ui.R

library(shiny)
library(shinyIncubator)

# Objective: Test app to see if I can input data into a database
# Currently no database connection is set up and this app just starts with uploading a simple csv file
# The data gets added to a temporary dataframe

shinyUI(pageWithSidebar(
  
  # Application title
  headerPanel("Test Form Input to Database"),
  
  sidebarPanel(

    # main type of view to select
    selectInput("menutype","Choose View Type",
                choices=c("ChooseOne","Projects","Project-Steps","Tasks")),
    
    # selection if Projects view is selected
    conditionalPanel(
      condition = "input.menutype == 'Projects'",
      selectInput("menuproj","Choose an Option",
                choices=c("ChooseOne","View Projects","Add New Project","Modify Existing Project"))
      )
    
    ),
  
  mainPanel(
    
    # view if Projects -> View Projects is selected
    conditionalPanel(
      condition = "input.menuproj == 'View Projects'",
      HTML("<h3> Project List </h3>"),
      verbatimTextOutput("projlist")
      ),
    
    # view if Projects -> Add Project is selected
    conditionalPanel(
      condition = "input.menuproj == 'Add New Project'",
      HTML("<h3> Add a New Project </h3>"),
      textInput("newproj","Input New Project Name"),
      selectInput("newstg","Current Project Stage",
                  choices=c("ChooseOne","Stg0","Stg1","Stg2")),
      textInput("newduedt","Next Due Date (YYYY-MM-DD)"),
      br(),
      actionButton("projnew","Add New Project"),
      verbatimTextOutput("newprojout")
      ),
    
    # view if Projects -> Modify existing project is selected
    conditionalPanel(
      condition = "input.menuproj == 'Modify Existing Project'",
      HTML("<h3> Modify an Existing Project </h3>"),
      uiOutput("projnames"),
      selectInput("modifstg","Current Project Stage",
                  choices=c("ChooseOne","Stg0","Stg1","Stg2")),
      textInput("modifduedt","Next Due Date (YYYY-MM-DD)"),
      br(),
      actionButton("projmodif","Modify Existing Project"),
      verbatimTextOutput("modifprojout")
      ),    
    
    # view if Project-Steps is selected (to Do)
    conditionalPanel(
      condition="input.menutype == 'Project-Steps'",
      HTML("<h3> To be Done </h3>")),
    
    # view if Tasks is selected (to Do)
    conditionalPanel(
      condition="input.menutype == 'Tasks'",
      HTML("<h3> To be Done </h3>"))
    
    
    )
  ))