在R闪亮中，如何在不使用renderUI的情况下首次调用应用程序时消除侧边栏中所有条件面板的闪烁？

Question

这是我 6 月 30 日帖子的后续内容，我在调用应用程序时消除了sidebarPanel 中闪烁的conditionalPanel。解决方案是将这些侧边栏条件面板移动到renderUI，消除闪烁。但是，后来我发现以这种方式使用renderUI 会导致其他限制。有什么方法可以在不使用renderUI的情况下消除调用闪烁？

我包含以下 3 组代码：

1. 很短的 MWE 代码说明了闪烁问题，由 ismirsehregal 提供
2. 长而复杂的代码非常清楚地说明了所有条件面板在调用时如何在侧面板中闪烁，当侧边栏条件面板在 UI 中呈现时（没有renderUI 用于侧边栏面板中的条件面板，如下面的#3解决了这个问题，尽管它引入了本文未解释的其他问题）。
3. 上述#2 的改编，其中使用了renderUI，并且没有调用闪烁。

我不想完全剥离第 2 项和第 3 项中的代码，以便侧边栏面板足够大，从而使调用闪烁更加明显。此外，当我对这段代码进行一些剥离时，我确实失去了一些功能，例如“重置”，无论如何这与手头的问题无关。

尽管 #2 和 #3 中的代码可能非常冗长且复杂，但将条件面板移动到 renderUI 是很简单的。

没有。 1 个短 MWE 代码：

  library(shiny)
    
    ui <- fluidPage(
      radioButtons("yourChoice", "Display button?", choices = c("Yes", "No"), selected = "No",),
      conditionalPanel("input.yourChoice == 'Yes'", actionButton("test", "test"))
      
      # not working: ------------------------------------------------------------
      # conditionalPanel("typeof input.yourChoice !== 'undefined' && input.yourChoice == 'Yes'", actionButton("test", "test"))
      # conditionalPanel("typeof input !== 'undefined' && input.yourChoice == 'Yes'", actionButton("test", "test"))
    )
    
    server <- function(input, output, session) {}
    
    shinyApp(ui, server)

没有。 2 没有renderUI的长代码，边栏调用闪烁：

library(shiny)
library(shinyMatrix)
library(shinyjs)
library(DT)

matrix1Input <- function(x){
  matrixInput(x, 
              value = matrix(c(0.2), 4, 1, dimnames = list(c("A","B","C","D"),NULL)),
              rows = list(extend = FALSE,  names = TRUE),
              cols = list(extend = FALSE, names = FALSE, editableNames = FALSE),
              class = "numeric")}

matrix2Input <- function(x,y,z){
  matrixInput(x,
              value = matrix(c(y,z),1,2,dimnames=list(NULL,c("Y","Z"))),
              rows = list(extend = TRUE,  names = FALSE),
              cols = list(extend = FALSE, names = TRUE, editableNames = FALSE),
              class = "numeric")}  

matrixLink <- function(x,y){
  observeEvent(input$periods|input$base_input,{
    updateMatrixInput(session,x,value=matrix(c(input$periods,y),1,2,dimnames=list(NULL, c("y","z"))))
  })} 

matrixValidate <- function(x,y){
  a <- y                                
  a[,1][a[,1]>x] <- x                   
  b <- diff(a[,1,drop=FALSE])           
  b[b<=0] <- NA                         
  b <- c(1,b)                           
  a <- cbind(a,b)                       
  a <- na.omit(a)                       
  a <- a[,-c(3),drop=FALSE]             
  return(a)}

vectorBase <- function(x,y){
  a <- rep(y,x)                         
  b <- seq(1:x)                         
  c <- data.frame(x = b, y = a)         
  return(c)}

vectorMulti <- function(x,y,z){                                            
  a <- rep(NA, x)                                                     
  a[y] <- z                                                           
  a[seq_len(min(y)-1)] <- a[min(y)]                                   
  if(max(y) < x){a[seq(max(y)+1, x, 1)] <- 0}                         
  a <- approx(seq_along(a)[!is.na(a)],a[!is.na(a)],seq_along(a))$y    
  b <- seq(1:x)                                                       
  c <- data.frame(x=b,z=a)                                            
  return(c)}

vectorMultiFinal <- function(x,y){vectorMulti(x,matrixValidate(x,y)[,1],matrixValidate(x,y)[,2])}

vectorPlot <- function(w,x,y,z){plot(w,main=x,xlab=y,ylab=z,type="b",col="blue",pch=19,cex=1.25)}

ui <- 
  
  pageWithSidebar(
    
    headerPanel("Model"),
    sidebarPanel(
      useShinyjs(),
      fluidRow(helpText(h4("Base Input Panel"))),
      
      conditionalPanel(condition="input.tabselected==1",h4("Select:")),
      
      conditionalPanel(
        condition="input.tabselected==2",
        sliderInput('periods','',min=1,max=120,value=60),
        matrix1Input("base_input"),
        actionButton('showVectorBtn','Show'), 
        actionButton('hideVectorBtn','Hide'),
        actionButton('resetVectorBtn','Reset'),
        hidden(uiOutput("Vectors"))
      ), # close conditional panel
      
    ), # close sidebar panel
    
    mainPanel(
      useShinyjs(),
      tabsetPanel(
        tabPanel("About model", value=1, helpText("Model")),
        tabPanel("By balances", value=2,
            fluidRow(
             radioButtons(
               inputId = 'mainPanelBtnTab2',
               label = h5(helpText("Asset outputs:")),
               choices = c('Vector plots','Vector values','Downloads'), 
               selected = 'Vector plots',
               inline = TRUE
             ) # close radio buttons
           ), # close fluid row
           
          conditionalPanel(condition="input.mainPanelBtnTab2=='Vector plots'",plotOutput("graph1")),
          conditionalPanel(condition="input.mainPanelBtnTab2=='Vector values'",DTOutput("table1")), 
        ),  # close tab panel
        id = "tabselected"
      ) # close tabset panel
    ) # close main panel
  ) # close page with sidebar

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

  periods                <- reactive(input$periods)
  base_input             <- reactive(input$base_input)
  yield_vector_input     <- reactive(input$yield_vector_input)
  chargeoff_vector_input <- reactive(input$chargeoff_vector_input)
  npr_vector_input       <- reactive(input$npr_vector_input)
  mpr_vector_input       <- reactive(input$mpr_vector_input)
  chargeoff              <- reactiveValues()
  npr                    <- reactiveValues()
  mpr                    <- reactiveValues()

  vectorVariable <- function(x,y){
    if(input$showVectorBtn == 0) vectorBase(input$periods,x)
    else vectorMultiFinal(input$periods,matrixValidate(input$periods,y))}  
  
  yield      <- function(){vectorVariable(input$base_input[1,1],yield_vector_input())}
  chargeoffs <- function(){vectorVariable(input$base_input[2,1],chargeoff_vector_input())}
  npr        <- function(){vectorVariable(input$base_input[3,1],npr_vector_input())}
  mpr        <- function(){vectorVariable(input$base_input[4,1],mpr_vector_input())}

  renderUI({ 
    matrixLink("yield_vector_input",input$base_input[1,1])
    matrixLink("chargeoff_vector_input",input$base_input[2,1])
    matrixLink("npr_vector_input",input$base_input[3,1])
    matrixLink("mpr_vector_input",input$base_input[4,1])
  }) # close renderUI
  
  output$Vectors <- renderUI({
    input$resetVectorBtn
    tagList(
      matrix2Input("yield_vector_input",input$periods,input$base_input[1,1]),
      matrix2Input("chargeoff_vector_input",input$periods,input$base_input[2,1]),
      matrix2Input("npr_vector_input",input$periods,input$base_input[3,1]),
      matrix2Input("mpr_vector_input",input$periods,input$base_input[4,1])
    ) # close tag list    
  }) # close render UI
  
  observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
  observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
  
  vectorsAll <- reactive({
    cbind(Period  = 1:periods(),
          Yld_Rate = yield()[,2],
          Chg_Rate = chargeoffs()[,2],
          Pur_Rate = npr()[,2],
          Pmt_Rate = mpr()[,2]
    ) # close cbind
  }) # close reactive
  
  output$graph1 <-renderPlot(vectorPlot(yield(),"Annual gross portfolio yield","Period","Rate"))
  
  output$table1 <- renderDT({vectorsAll()},
                            options=list(columnDefs=list(list(className='dt-center',targets=0:4)))
  ) # close renderDT

  output$balancePlot <- renderPlot({vectorPlot(bal(),"Asset bal","Period","Balances OS")})

  output$download <- downloadHandler(
    filename = function() {{paste("Yield","png",sep=".")}},
    content = function(file){
        png(file)
        vectorPlot(yield(),"Annual yield","Period","Rate")
        dev.off()
    } # close content function
  ) # close download handler
  
  observeEvent(input$mainPanelBtnTab2,{
    req(input$mainPanelBtnTab2 == "Downloads")
    showModal(
      modalDialog(
        selectInput("downloadItem","Selection:",c("Yield plot")), 
        downloadButton("download", "Download")
      ) # close modal dialog
    ) # close show modal
    updateRadioButtons(inputId = "mainPanelBtnTab2", selected = "Vector plots")
  }) # close observeEvent

}) # close server

shinyApp(ui, server)

没有。 3 用renderUI 重新处理#2 的长代码，并且没有侧边栏调用闪烁（省略自定义函数，因为它们与上面的代码相同）：

ui <- 
  
  pageWithSidebar(
    
    headerPanel("Model"),
    sidebarPanel(
      useShinyjs(),
      fluidRow(helpText(h4("Base Input Panel"))),
      
      uiOutput("Panels")
      
    ), # close sidebar panel
    
    mainPanel(
      useShinyjs(),
      tabsetPanel(
        tabPanel("About model", value=1, helpText("Model")),
        tabPanel("By balances", value=2,
                 fluidRow(
                   radioButtons(
                     inputId = 'mainPanelBtnTab2',
                     label = h5(helpText("Asset outputs:")),
                     choices = c('Vector plots','Vector values','Downloads'), 
                     selected = 'Vector plots',
                     inline = TRUE
                   ) # close radio buttons
                 ), # close fluid row
                 
                 conditionalPanel(condition="input.mainPanelBtnTab2=='Vector plots'",plotOutput("graph1")),
                 conditionalPanel(condition="input.mainPanelBtnTab2=='Vector values'",DTOutput("table1")), 
        ),  # close tab panel
        id = "tabselected"
      ) # close tabset panel
    ) # close main panel
  ) # close page with sidebar

server <- function(input,output,session)({
  
  periods                <- reactive(input$periods)
  base_input             <- reactive(input$base_input)
  yield_vector_input     <- reactive(input$yield_vector_input)
  chargeoff_vector_input <- reactive(input$chargeoff_vector_input)
  npr_vector_input       <- reactive(input$npr_vector_input)
  mpr_vector_input       <- reactive(input$mpr_vector_input)
  chargeoff              <- reactiveValues()
  npr                    <- reactiveValues()
  mpr                    <- reactiveValues()
  
  vectorVariable <- function(x,y){
    if(input$showVectorBtn == 0) vectorBase(input$periods,x)
    else vectorMultiFinal(input$periods,matrixValidate(input$periods,y))}  
  
  yield      <- function(){vectorVariable(input$base_input[1,1],yield_vector_input())}
  chargeoffs <- function(){vectorVariable(input$base_input[2,1],chargeoff_vector_input())}
  npr        <- function(){vectorVariable(input$base_input[3,1],npr_vector_input())}
  mpr        <- function(){vectorVariable(input$base_input[4,1],mpr_vector_input())}
  
  output$Panels <- renderUI({
   tagList(
     conditionalPanel(condition="input.tabselected==1",h4("Select:")),
     
     conditionalPanel(
       condition="input.tabselected==2",
       sliderInput('periods','',min=1,max=120,value=60),
       matrix1Input("base_input"),
       actionButton('showVectorBtn','Show'), 
       actionButton('hideVectorBtn','Hide'),
       actionButton('resetVectorBtn','Reset'),
       hidden(uiOutput("Vectors"))
     ), # close conditional panel
   ) # close tag list
  }) # close renderUI
  
  renderUI({ 
    matrixLink("yield_vector_input",input$base_input[1,1])
    matrixLink("chargeoff_vector_input",input$base_input[2,1])
    matrixLink("npr_vector_input",input$base_input[3,1])
    matrixLink("mpr_vector_input",input$base_input[4,1])
  }) # close renderUI
  
  output$Vectors <- renderUI({
    input$resetVectorBtn
    tagList(
      matrix2Input("yield_vector_input",input$periods,input$base_input[1,1]),
      matrix2Input("chargeoff_vector_input",input$periods,input$base_input[2,1]),
      matrix2Input("npr_vector_input",input$periods,input$base_input[3,1]),
      matrix2Input("mpr_vector_input",input$periods,input$base_input[4,1])
    ) # close tag list    
  }) # close render UI
  
  observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
  observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
  
  vectorsAll <- reactive({
    cbind(Period  = 1:periods(),
          Yld_Rate = yield()[,2],
          Chg_Rate = chargeoffs()[,2],
          Pur_Rate = npr()[,2],
          Pmt_Rate = mpr()[,2]
    ) # close cbind
  }) # close reactive
  
  output$graph1 <-renderPlot(vectorPlot(yield(),"Annual gross portfolio yield","Period","Rate"))
  
  output$table1 <- renderDT({vectorsAll()},
                            options=list(columnDefs=list(list(className='dt-center',targets=0:4)))
  ) # close renderDT
  
  output$balancePlot <- renderPlot({vectorPlot(bal(),"Asset bal","Period","Balances OS")})
  
  output$download <- downloadHandler(
    filename = function() {{paste("Yield","png",sep=".")}},
    content = function(file){
      png(file)
      vectorPlot(yield(),"Annual yield","Period","Rate")
      dev.off()
    } # close content function
  ) # close download handler
  
  observeEvent(input$mainPanelBtnTab2,{
    req(input$mainPanelBtnTab2 == "Downloads")
    showModal(
      modalDialog(
        selectInput("downloadItem","Selection:",c("Yield plot")), 
        downloadButton("download", "Download")
      ) # close modal dialog
    ) # close show modal
    updateRadioButtons(inputId = "mainPanelBtnTab2", selected = "Vector plots")
  }) # close observeEvent
  
}) # close server

shinyApp(ui, server)

Answer 1

现在我得到了一些feedback on GitHub。

设置style = "display: none;"可以避免闪烁。

在 UI 中解决这个问题，而不是使用基于服务器的解决方法（@EliBerkow 的回答）可以更快地加载 UI。

library(shiny)

ui <- fluidPage(
  radioButtons("yourChoice", "Display button?", choices = c("Yes", "No"), selected = "No",),
  conditionalPanel("input.yourChoice == 'Yes'", style = "display: none;", actionButton("test", "test"))
)

server <- function(input, output, session) {}

shinyApp(ui, server)

---

应用于@CuriousJorge-user9788072 的代码：

library(shiny)
library(shinyMatrix)
library(shinyjs)
library(DT)

matrix1Input <- function(x){
  matrixInput(x, 
              value = matrix(c(0.2), 4, 1, dimnames = list(c("A","B","C","D"),NULL)),
              rows = list(extend = FALSE,  names = TRUE),
              cols = list(extend = FALSE, names = FALSE, editableNames = FALSE),
              class = "numeric")}

matrix2Input <- function(x,y,z){
  matrixInput(x,
              value = matrix(c(y,z),1,2,dimnames=list(NULL,c("Y","Z"))),
              rows = list(extend = TRUE,  names = FALSE),
              cols = list(extend = FALSE, names = TRUE, editableNames = FALSE),
              class = "numeric")}  

matrixLink <- function(x,y){
  observeEvent(input$periods|input$base_input,{
    updateMatrixInput(session,x,value=matrix(c(input$periods,y),1,2,dimnames=list(NULL, c("y","z"))))
  })} 

matrixValidate <- function(x,y){
  a <- y                                
  a[,1][a[,1]>x] <- x                   
  b <- diff(a[,1,drop=FALSE])           
  b[b<=0] <- NA                         
  b <- c(1,b)                           
  a <- cbind(a,b)                       
  a <- na.omit(a)                       
  a <- a[,-c(3),drop=FALSE]             
  return(a)}

vectorBase <- function(x,y){
  a <- rep(y,x)                         
  b <- seq(1:x)                         
  c <- data.frame(x = b, y = a)         
  return(c)}

vectorMulti <- function(x,y,z){                                            
  a <- rep(NA, x)                                                     
  a[y] <- z                                                           
  a[seq_len(min(y)-1)] <- a[min(y)]                                   
  if(max(y) < x){a[seq(max(y)+1, x, 1)] <- 0}                         
  a <- approx(seq_along(a)[!is.na(a)],a[!is.na(a)],seq_along(a))$y    
  b <- seq(1:x)                                                       
  c <- data.frame(x=b,z=a)                                            
  return(c)}

vectorMultiFinal <- function(x,y){vectorMulti(x,matrixValidate(x,y)[,1],matrixValidate(x,y)[,2])}

vectorPlot <- function(w,x,y,z){plot(w,main=x,xlab=y,ylab=z,type="b",col="blue",pch=19,cex=1.25)}

ui <- 
  
  pageWithSidebar(
    
    headerPanel("Model"),
    sidebarPanel(
      useShinyjs(),
      fluidRow(helpText(h4("Base Input Panel"))),
      
      conditionalPanel(condition="input.tabselected==1",h4("Select:")),
      
      conditionalPanel(
        condition="input.tabselected==2",
        sliderInput('periods','',min=1,max=120,value=60),
        matrix1Input("base_input"),
        actionButton('showVectorBtn','Show'), 
        actionButton('hideVectorBtn','Hide'),
        actionButton('resetVectorBtn','Reset'),
        hidden(uiOutput("Vectors")),
        style = "display: none;"
      ), # close conditional panel
      
    ), # close sidebar panel
    
    mainPanel(
      useShinyjs(),
      tabsetPanel(
        tabPanel("About model", value=1, helpText("Model")),
        tabPanel("By balances", value=2,
                 fluidRow(
                   radioButtons(
                     inputId = 'mainPanelBtnTab2',
                     label = h5(helpText("Asset outputs:")),
                     choices = c('Vector plots','Vector values','Downloads'), 
                     selected = 'Vector plots',
                     inline = TRUE
                   ) # close radio buttons
                 ), # close fluid row
                 
                 conditionalPanel(condition="input.mainPanelBtnTab2=='Vector plots'",plotOutput("graph1")),
                 conditionalPanel(condition="input.mainPanelBtnTab2=='Vector values'",DTOutput("table1")), 
        ),  # close tab panel
        id = "tabselected"
      ) # close tabset panel
    ) # close main panel
  ) # close page with sidebar

server <- function(input,output,session)({
  
  periods                <- reactive(input$periods)
  base_input             <- reactive(input$base_input)
  yield_vector_input     <- reactive(input$yield_vector_input)
  chargeoff_vector_input <- reactive(input$chargeoff_vector_input)
  npr_vector_input       <- reactive(input$npr_vector_input)
  mpr_vector_input       <- reactive(input$mpr_vector_input)
  chargeoff              <- reactiveValues()
  npr                    <- reactiveValues()
  mpr                    <- reactiveValues()
  
  vectorVariable <- function(x,y){
    if(input$showVectorBtn == 0) vectorBase(input$periods,x)
    else vectorMultiFinal(input$periods,matrixValidate(input$periods,y))}  
  
  yield      <- function(){vectorVariable(input$base_input[1,1],yield_vector_input())}
  chargeoffs <- function(){vectorVariable(input$base_input[2,1],chargeoff_vector_input())}
  npr        <- function(){vectorVariable(input$base_input[3,1],npr_vector_input())}
  mpr        <- function(){vectorVariable(input$base_input[4,1],mpr_vector_input())}
  
  renderUI({ 
    matrixLink("yield_vector_input",input$base_input[1,1])
    matrixLink("chargeoff_vector_input",input$base_input[2,1])
    matrixLink("npr_vector_input",input$base_input[3,1])
    matrixLink("mpr_vector_input",input$base_input[4,1])
  }) # close renderUI
  
  output$Vectors <- renderUI({
    input$resetVectorBtn
    tagList(
      matrix2Input("yield_vector_input",input$periods,input$base_input[1,1]),
      matrix2Input("chargeoff_vector_input",input$periods,input$base_input[2,1]),
      matrix2Input("npr_vector_input",input$periods,input$base_input[3,1]),
      matrix2Input("mpr_vector_input",input$periods,input$base_input[4,1])
    ) # close tag list    
  }) # close render UI
  
  observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
  observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
  
  vectorsAll <- reactive({
    cbind(Period  = 1:periods(),
          Yld_Rate = yield()[,2],
          Chg_Rate = chargeoffs()[,2],
          Pur_Rate = npr()[,2],
          Pmt_Rate = mpr()[,2]
    ) # close cbind
  }) # close reactive
  
  output$graph1 <-renderPlot(vectorPlot(yield(),"Annual gross portfolio yield","Period","Rate"))
  
  output$table1 <- renderDT({vectorsAll()},
                            options=list(columnDefs=list(list(className='dt-center',targets=0:4)))
  ) # close renderDT
  
  output$balancePlot <- renderPlot({vectorPlot(bal(),"Asset bal","Period","Balances OS")})
  
  output$download <- downloadHandler(
    filename = function() {{paste("Yield","png",sep=".")}},
    content = function(file){
      png(file)
      vectorPlot(yield(),"Annual yield","Period","Rate")
      dev.off()
    } # close content function
  ) # close download handler
  
  observeEvent(input$mainPanelBtnTab2,{
    req(input$mainPanelBtnTab2 == "Downloads")
    showModal(
      modalDialog(
        selectInput("downloadItem","Selection:",c("Yield plot")), 
        downloadButton("download", "Download")
      ) # close modal dialog
    ) # close show modal
    updateRadioButtons(inputId = "mainPanelBtnTab2", selected = "Vector plots")
  }) # close observeEvent
  
}) # close server

shinyApp(ui, server)

Answer 2

在服务器中使用observeEvent 而不是在用户界面中使用conditionalPanel，如下所示（参见#Added Code）。我还需要向h4() 添加一个ID，并从前面的所有第二个标签边栏按钮hidden 开始。最后我将ignoreInit = TRUE 添加到observeEvent，因为它最初是不必要的：

library(shiny)
library(shinyMatrix)
library(shinyjs)
library(DT)

matrix1Input <- function(x){
    matrixInput(x, 
                value = matrix(c(0.2), 4, 1, dimnames = list(c("A","B","C","D"),NULL)),
                rows = list(extend = FALSE,  names = TRUE),
                cols = list(extend = FALSE, names = FALSE, editableNames = FALSE),
                class = "numeric")}

matrix2Input <- function(x,y,z){
    matrixInput(x,
                value = matrix(c(y,z),1,2,dimnames=list(NULL,c("Y","Z"))),
                rows = list(extend = TRUE,  names = FALSE),
                cols = list(extend = FALSE, names = TRUE, editableNames = FALSE),
                class = "numeric")}  

matrixLink <- function(x,y){
    observeEvent(input$periods|input$base_input,{
        updateMatrixInput(session,x,value=matrix(c(input$periods,y),1,2,dimnames=list(NULL, c("y","z"))))
    })} 

matrixValidate <- function(x,y){
    a <- y                                
    a[,1][a[,1]>x] <- x                   
    b <- diff(a[,1,drop=FALSE])           
    b[b<=0] <- NA                         
    b <- c(1,b)                           
    a <- cbind(a,b)                       
    a <- na.omit(a)                       
    a <- a[,-c(3),drop=FALSE]             
    return(a)}

vectorBase <- function(x,y){
    a <- rep(y,x)                         
    b <- seq(1:x)                         
    c <- data.frame(x = b, y = a)         
    return(c)}

vectorMulti <- function(x,y,z){                                            
    a <- rep(NA, x)                                                     
    a[y] <- z                                                           
    a[seq_len(min(y)-1)] <- a[min(y)]                                   
    if(max(y) < x){a[seq(max(y)+1, x, 1)] <- 0}                         
    a <- approx(seq_along(a)[!is.na(a)],a[!is.na(a)],seq_along(a))$y    
    b <- seq(1:x)                                                       
    c <- data.frame(x=b,z=a)                                            
    return(c)}

vectorMultiFinal <- function(x,y){vectorMulti(x,matrixValidate(x,y)[,1],matrixValidate(x,y)[,2])}

vectorPlot <- function(w,x,y,z){plot(w,main=x,xlab=y,ylab=z,type="b",col="blue",pch=19,cex=1.25)}

ui <- 
    
    pageWithSidebar(
        
        headerPanel("Model"),
        sidebarPanel(
            useShinyjs(),
            fluidRow(helpText(h4("Base Input Panel"))),
            
            h4(id = 'select', "Select:", ),
            
            hidden(sliderInput('periods','',min=1,max=120,value=60)),
            hidden(matrix1Input("base_input")),
            hidden(actionButton('showVectorBtn','Show')), 
            hidden(actionButton('hideVectorBtn','Hide')),
            hidden(actionButton('resetVectorBtn','Reset')),
            hidden(uiOutput("Vectors"))
            
            
        ), # close sidebar panel
        
        mainPanel(
            useShinyjs(),
            tabsetPanel(
                tabPanel("About model", value=1, helpText("Model")),
                tabPanel("By balances", value=2,
                         fluidRow(
                             radioButtons(
                                 inputId = 'mainPanelBtnTab2',
                                 label = h5(helpText("Asset outputs:")),
                                 choices = c('Vector plots','Vector values','Downloads'), 
                                 selected = 'Vector plots',
                                 inline = TRUE
                             ) # close radio buttons
                         ), # close fluid row
                         
                         conditionalPanel(condition="input.mainPanelBtnTab2=='Vector plots'",plotOutput("graph1")),
                         conditionalPanel(condition="input.mainPanelBtnTab2=='Vector values'",DTOutput("table1")), 
                ),  # close tab panel
                id = "tabselected"
            ) # close tabset panel
        ) # close main panel
    ) # close page with sidebar

server <- function(input,output,session)({
    
    periods                <- reactive(input$periods)
    base_input             <- reactive(input$base_input)
    yield_vector_input     <- reactive(input$yield_vector_input)
    chargeoff_vector_input <- reactive(input$chargeoff_vector_input)
    npr_vector_input       <- reactive(input$npr_vector_input)
    mpr_vector_input       <- reactive(input$mpr_vector_input)
    chargeoff              <- reactiveValues()
    npr                    <- reactiveValues()
    mpr                    <- reactiveValues()
    
    vectorVariable <- function(x,y){
        if(input$showVectorBtn == 0) vectorBase(input$periods,x)
        else vectorMultiFinal(input$periods,matrixValidate(input$periods,y))}  
    
    yield      <- function(){vectorVariable(input$base_input[1,1],yield_vector_input())}
    chargeoffs <- function(){vectorVariable(input$base_input[2,1],chargeoff_vector_input())}
    npr        <- function(){vectorVariable(input$base_input[3,1],npr_vector_input())}
    mpr        <- function(){vectorVariable(input$base_input[4,1],mpr_vector_input())}
    
    renderUI({ 
        matrixLink("yield_vector_input",input$base_input[1,1])
        matrixLink("chargeoff_vector_input",input$base_input[2,1])
        matrixLink("npr_vector_input",input$base_input[3,1])
        matrixLink("mpr_vector_input",input$base_input[4,1])
    }) # close renderUI
    
    output$Vectors <- renderUI({
        input$resetVectorBtn
        tagList(
            matrix2Input("yield_vector_input",input$periods,input$base_input[1,1]),
            matrix2Input("chargeoff_vector_input",input$periods,input$base_input[2,1]),
            matrix2Input("npr_vector_input",input$periods,input$base_input[3,1]),
            matrix2Input("mpr_vector_input",input$periods,input$base_input[4,1])
        ) # close tag list    
    }) # close render UI


    # Added Code
    observeEvent(input$tabselected, {
        if (input$tabselected == 1) {
            show('select')
            hide('periods')
            hide("base_input")
            hide('showVectorBtn') 
            hide('hideVectorBtn')
            hide('resetVectorBtn')
        } else {
            hide('select')
            show('periods')
            show("base_input")
            show('showVectorBtn') 
            show('hideVectorBtn')
            show('resetVectorBtn')
        }
    }, ignoreInit = TRUE)
    
    observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
    observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
    
    vectorsAll <- reactive({
        cbind(Period  = 1:periods(),
              Yld_Rate = yield()[,2],
              Chg_Rate = chargeoffs()[,2],
              Pur_Rate = npr()[,2],
              Pmt_Rate = mpr()[,2]
        ) # close cbind
    }) # close reactive
    
    output$graph1 <-renderPlot(vectorPlot(yield(),"Annual gross portfolio yield","Period","Rate"))
    
    output$table1 <- renderDT({vectorsAll()},
                              options=list(columnDefs=list(list(className='dt-center',targets=0:4)))
    ) # close renderDT
    
    output$balancePlot <- renderPlot({vectorPlot(bal(),"Asset bal","Period","Balances OS")})
    
    output$download <- downloadHandler(
        filename = function() {{paste("Yield","png",sep=".")}},
        content = function(file){
            png(file)
            vectorPlot(yield(),"Annual yield","Period","Rate")
            dev.off()
        } # close content function
    ) # close download handler
    
    observeEvent(input$mainPanelBtnTab2,{
        req(input$mainPanelBtnTab2 == "Downloads")
        showModal(
            modalDialog(
                selectInput("downloadItem","Selection:",c("Yield plot")), 
                downloadButton("download", "Download")
            ) # close modal dialog
        ) # close show modal
        updateRadioButtons(inputId = "mainPanelBtnTab2", selected = "Vector plots")
    }) # close observeEvent
    
}) # close server

shinyApp(ui, server)