光沢のある入力で「引数が無効です」というメッセージエラー

Question

このコードに条件を追加して、異なるselectinputが空の場合のメッセージエラーを回避します。私は反応式でreq()を使用しようとしましたが、うまくいきませんでした。

l <- NULL 
l$name <- c('b','e','d','b','b','d','e','e','b','b') 
l$age <- c(20,20,21,21,20,22,22,30,21,32) 
l$gender <- c('Female', 'Female', 'Male', 'Female', 'Male','Male', 
       'Female','Male',"Female","Male") 
l <- as.data.frame(l) 
l$name <- as.character(l$name) 
l$age <- as.numeric(l$age) 
l$gender <- as.character(l$gender) 


library(shiny) 
server <- shinyServer(function(input,output){ 

    assign('All Names', unique(sort(l$name))) 
    assign("All Ages", unique(sort(l$age))) 
    assign('All Genders', unique(sort(l$gender))) 

    data1 <- reactive(l[which(l$name %in% if(exists(input$name)) 
    {get(input$name)}else{input$name}),]) 


    data2 <- reactive(data1()[which(data1()$age %in% if(exists(input$age)) 
    {get(input$age)}else{input$age}),]) 


    data3 <- eventReactive(input$go_baba, { 
    data2()[which(data2()$gender %in% if(exists(input$gender)) 
    {get(input$gender)}else{input$gender}),] 
    }) 

    output$table3 <- renderTable(data3()) 


    output$Box1 = renderUI(
    if((is.null(input$age)) & (is.null(input$gender))){ 
     selectInput("name", "Choose Name", choices=c("All Names",unique(sort(l$name))), selected = input$name) 
    } else{selectInput("name", "Choose Name", choices=c("All Names",unique(l[l$gender %in% (if(exists(input$gender)){get(input$gender)}else{input$gender}) & l$age %in% (if(exists(input$age)){get(input$age)}else{input$age}) , "name"])), selected = input$name, multiple = T) 
    } 
) 



    output$Box2 = renderUI(
    if((is.null(input$name)) & (is.null(input$gender))){ 
     selectInput("age", "Choose Age", choices=c("All Ages", unique(sort(l$age))), selected = input$age) 
    }else{selectInput("age", "Choose Age", choices=c("All Ages",unique(l[l$gender %in% (if(exists(input$gender)){get(input$gender)}else{input$gender}) & l$name %in% (if(exists(input$name)){get(input$name)}else{input$name}) , "age"])), selected = input$age, multiple = T)} 
) 

    output$Box3 = renderUI(
    if((is.null(input$name)) & (is.null(input$age))){ 
     selectInput("gender", "Choose Gender", choices=c("All Genders", unique(sort(l$gender))), selected = input$gender) 
    }else{ 

     selectInput("gender", "Choose Gender", choices=c("All Genders", unique(l[l$name %in% (if(exists(input$name)){get(input$name)}else{input$name}) & l$age %in% (if(exists(input$age)){get(input$age)}else{input$age}), "gender"])), selected = input$gender, multiple = TRUE) 
    } 
) 



}) 

ui <-shinyUI(fluidPage(
    uiOutput("Box1"), 
    uiOutput("Box2"), 
    uiOutput("Box3"), 
    actionButton("go_baba", "GO !"), 
    tableOutput("table3") 
)) 

shinyApp(ui,server) 

Answer 1

この場合、便利なツールがvalidate(need(condition, message))です：私はまた、任意の助けが

コードを理解さウィル..あまりにも異なる入力が、doesntの仕事のためにif(input$name == NULL){return(NULL)}のような条件を追加し

を試してみました。条件が満たされずに現在の出力の実行を停止すると、メッセージが表示されます。詳細情報here。代わりにreq(!is.null(input$...))を使用することもできますが、メッセージはまったく同じ効果があります。

私はそれを読みやすくするために、あなたのコードを書き直しました：私のコンピュータ上の

library(shiny) 

l <- data.frame(name = c('b','e','d','b','b','d','e','e','b','b'), 
       age = c(20,20,21,21,20,22,22,30,21,32), 
       gender = c('Female', 'Female', 'Male', 'Female', 'Male','Male', 'Female','Male',"Female","Male"), 
       stringsAsFactors = F) 

server <- shinyServer(function(input,output){ 

    # subset l according to inputs 
    data <- eventReactive(input$go_baba, { 
    out <- l 
    if(!"All Names" %in% input$name) out <- subset(l, name %in% input$name) 
    if(!"All Ages" %in% input$age) out <- subset(l, age %in% input$age) 
    if(!"All Genders" %in% input$gender) out <- subset(l, gender %in% input$gender) 
    return(out) 
    }) 

    # display the result as table 
    output$table3 <- renderTable({ 
    data() 
    }) 

    # selectInput for Date 
    output$Box1 = renderUI({ 
     selectInput("name", "Choose Name", choices=c("All Names", unique(sort(l$name))), selected=NULL, multiple=T) 
    }) 

    # selectInput for Age 
    output$Box2 = renderUI({ 
    validate(need(!is.null(input$name), "Please choose a name")) 
    selectInput("age", "Choose Age", choices=c("All Ages", unique(l$age)), selected=NULL, 
       multiple = T) 
    }) 

    # selectInput for Gender 
    output$Box3 = renderUI({ 
    validate(need(!is.null(input$age), "Please choose an age")) 
    selectInput("gender", "Choose Gender", choices=c("All Genders", unique(l$gender)), selected=NULL) 
    }) 
}) 

ui <-shinyUI(fluidPage(
    uiOutput("Box1"), 
    uiOutput("Box2"), 
    uiOutput("Box3"), 

    conditionalPanel(condition="input.age != null & input.gender != null", actionButton("go_baba", "GO !")), 
    tableOutput("table3") 
)) 

shinyApp(ui,server)