在 R shiny 中调用 downloadHandler 函数时，如何生成带有选择提示的弹出窗口，提示要下载哪个对象？
How to generate a pop up with a selection prompt for which object to download when invoking the downloadHandler function in R shiny?
在下面的 MWE 代码中，downloadHandler 成功地允许用户下载下面在函数 vectorVariable(input$base_input[1,1],vector1_input()) 中定义的第一个绘图“vector1”。但是，我正在尝试修改下面的内容，以便在单击下载按钮时，系统会通过弹出窗口提示用户下载 selection 下载 vector1 或 vector2，后者在函数 [=13 中定义如下=].
有人可以帮我编写一个带有某种 selectInput 或类似下载对象的条件弹出窗口，通过单击下载按钮触发吗？
我试图坚持使用本机 Shiny 函数 downloadHandler 因为它在提示用户选择下载目录方面做得非常好。我发现在 downloadHandler.
之外很难做到这一点
请注意，在这个 MWE 派生的完整应用程序中，有两个以上的 PNG 文件可供 select 下载。此外，在完整的应用程序中，相同的下载按钮用于单独的 server 部分，此 MWE 中未显示用于下载数据表（效果很好）---因此对象下载的任何更改 selection 需要在 server 部分中完成，而 UI 部分中的 downloadButton("download", "Download") 保持不变，因为它处理的不仅仅是此 MWE 中显示的这些 PNG 文件（我想这意味着某种 renderUI...).
MWE 代码：
library(shiny)
library(shinyMatrix)
library(shinyjs)
library(DT)
matrix1.input <- function(x){
matrixInput(x,
value = matrix(c(0.2), 2, 1, dimnames = list(c("A","B"),NULL)),
rows = list(extend = FALSE, names = TRUE),
cols = list(extend = FALSE, names = FALSE, editableNames = FALSE),
class = "numeric")}
matrix2.input <- function(x,y,z){
matrixInput(x,
value = matrix(c(y,z),1,2,dimnames=list(NULL,c("Y","Z"))),
rows = list(extend = TRUE, names = FALSE),
cols = list(extend = FALSE, names = TRUE, editableNames = FALSE),
class = "numeric")}
matrix.validate <- function(x,y){
a <- y
a[,1][a[,1]>x] <- x
b <- diff(a[,1,drop=FALSE])
b[b<=0] <- NA
b <- c(1,b)
a <- cbind(a,b)
a <- na.omit(a)
a <- a[,-c(3),drop=FALSE]
return(a)}
vector.base <- function(x,y){
a <- rep(y,x)
b <- seq(1:x)
c <- data.frame(x = b, y = a)
return(c)}
vector.multi <- function(x,y,z){
a <- rep(NA, x)
a[y] <- z
a[seq_len(min(y)-1)] <- a[min(y)]
if(max(y) < x){a[seq(max(y)+1, x, 1)] <- 0}
a <- approx(seq_along(a)[!is.na(a)],a[!is.na(a)],seq_along(a))$y
b <- seq(1:x)
c <- data.frame(x = b, z = a)
return(c)}
vector.multiFinal <- function(x,y){
vector.multi(x,matrix.validate(x,y)[,1],matrix.validate(x,y)[,2])}
matrix.link <- function(x,y){
observeEvent(input$periods|input$base_input,{
updateMatrixInput(session,x,value=matrix(c(input$periods,y),1,2,dimnames=list(NULL, c("y","z"))))})}
ui <-
pageWithSidebar(
headerPanel("Model"),
sidebarPanel(uiOutput("Panels")),
mainPanel(
tabsetPanel(
tabPanel("Dynamic", value=2,
actionButton('showVectorPlotBtn','Vector plots'),
actionButton('showVectorValueBtn','Vector values'),
downloadButton("download", "Download"),
uiOutput("vectorTable")),
id = "tabselected")
) # close main panel
) # close page with sidebar
server <- function(input,output,session)({
periods <- reactive(input$periods)
base_input <- reactive(input$base_input)
vector1_input <- reactive(input$vector1_input)
vector2_input <- reactive(input$vector2_input)
yld <- reactiveValues()
vectorVariable <- function(x,y){
if(input$showVectorBtn == 0) vector.base(input$periods,x)
else vector.multiFinal(input$periods,matrix.validate(input$periods,y))}
output$Panels <- renderUI({
tagList(
conditionalPanel(
condition="input.tabselected==2",
sliderInput('periods','',min=1,max=120,value=60),
matrix1.input("base_input"),
useShinyjs(),
actionButton('showVectorBtn','Show'),
actionButton('hideVectorBtn','Hide'),
actionButton('resetVectorBtn','Reset'),
hidden(uiOutput("Vectors"))))})
renderUI({
matrix.link("vector1_input",input$base_input[1,1])
matrix.link("vector2_input",input$base_input[2,1])})
output$Vectors <- renderUI({input$resetVectorBtn
tagList(matrix2.input("vector1_input",input$periods,input$base_input[1,1]),
matrix2.input("vector2_input",input$periods,input$base_input[2,1]))})
observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
output$graph1 <- renderPlot(plot(vectorVariable(input$base_input[1,1],vector1_input())))
output$graph2 <- renderPlot(plot(vectorVariable(input$base_input[2,1],vector2_input())))
output$download <- downloadHandler(
filename = function() {paste("vector1","png",sep=".")},
content = function(file){
png(file)
plot(vectorVariable(input$base_input[1,1],vector1_input()))
dev.off()}
) # close download handler
output$table1 <- renderDT({vectorsAll()})
observeEvent(input$showVectorPlotBtn,{yld$showme <- tagList(plotOutput("graph1"), plotOutput("graph2"))},ignoreNULL = FALSE)
observeEvent(input$showVectorValueBtn,{yld$showme <- DTOutput("table1")})
output$vectorTable <- renderUI({yld$showme})
vectorsAll <- reactive({
cbind(1:periods(),
vectorVariable(input$base_input[1,1],vector1_input())[,2],
vectorVariable(input$base_input[2,1],vector2_input())[,2])})})
shinyApp(ui, server)
为了回应 ismirsehregal 的评论，下面是使用 actionButton 的工作 MWE，它触发一个带有 selectInput 和下载按钮的模态插入到所述模态中。这是来自 ismirsehregal 的干净解决方案。
MWE 代码（为简洁起见，省略了原始 MWE 中的库和函数定义；如果您想 运行 下面的 MWE，请确保从上面复制库和定义的函数！ !):
ui <-
pageWithSidebar(
headerPanel("Model"),
sidebarPanel(uiOutput("Panels")),
mainPanel(
tabsetPanel(
tabPanel("Dynamic", value=2,
actionButton('showVectorPlotBtn','Vector plots'),
actionButton('showVectorValueBtn','Vector values'),
actionButton("showDownload", "Download"),
uiOutput("vectorTable")),
id = "tabselected")
) # close main panel
) # close page with sidebar
server <- function(input,output,session)({
periods <- reactive(input$periods)
base_input <- reactive(input$base_input)
vector1_input <- reactive(input$vector1_input)
vector2_input <- reactive(input$vector2_input)
yld <- reactiveValues()
vectorVariable <- function(x,y){
if(input$showVectorBtn == 0) vector.base(input$periods,x)
else vector.multiFinal(input$periods,matrix.validate(input$periods,y))}
output$Panels <- renderUI({
tagList(
conditionalPanel(
condition="input.tabselected==2",
sliderInput('periods','',min=1,max=120,value=60),
matrix1.input("base_input"),
useShinyjs(),
actionButton('showVectorBtn','Show'),
actionButton('hideVectorBtn','Hide'),
actionButton('resetVectorBtn','Reset'),
hidden(uiOutput("Vectors"))))})
renderUI({
matrix.link("vector1_input",input$base_input[1,1])
matrix.link("vector2_input",input$base_input[2,1])})
output$Vectors <- renderUI({input$resetVectorBtn
tagList(matrix2.input("vector1_input",input$periods,input$base_input[1,1]),
matrix2.input("vector2_input",input$periods,input$base_input[2,1]))})
observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
output$graph1 <- renderPlot(plot(vectorVariable(input$base_input[1,1],vector1_input())))
output$graph2 <- renderPlot(plot(vectorVariable(input$base_input[2,1],vector2_input())))
output$download <- downloadHandler(
filename = function() {
if (input$downloadItem == "Vector1") {paste("Vector1","png",sep=".")}
else {paste("Vector2","png",sep=".")}
},
content = function(file){
png(file)
if (input$downloadItem == "Vector1"){plot(vectorVariable(input$base_input[1,1],vector1_input()))}
else {plot(vectorVariable(input$base_input[2,1],vector2_input()))}
dev.off()}
) # close download handler
observeEvent(input$showDownload,
{showModal(modalDialog(
selectInput("downloadItem","Select item to download:",
c("Vector1","Vector2")),
downloadButton("download", "Download")
) # close modalDialog
) # close showModal
} # close showModal function
) # close observeEvent
output$table1 <- renderDT({vectorsAll()})
observeEvent(input$showVectorPlotBtn,{yld$showme <- tagList(plotOutput("graph1"), plotOutput("graph2"))},ignoreNULL = FALSE)
observeEvent(input$showVectorValueBtn,{yld$showme <- DTOutput("table1")})
output$vectorTable <- renderUI({yld$showme})
vectorsAll <- reactive({
cbind(1:periods(),
vectorVariable(input$base_input[1,1],vector1_input())[,2],
vectorVariable(input$base_input[2,1],vector2_input())[,2])})})
shinyApp(ui, server)
在下面的 MWE 代码中，downloadHandler 成功地允许用户下载下面在函数 vectorVariable(input$base_input[1,1],vector1_input()) 中定义的第一个绘图“vector1”。但是，我正在尝试修改下面的内容，以便在单击下载按钮时，系统会通过弹出窗口提示用户下载 selection 下载 vector1 或 vector2，后者在函数 [=13 中定义如下=].
有人可以帮我编写一个带有某种 selectInput 或类似下载对象的条件弹出窗口，通过单击下载按钮触发吗？
我试图坚持使用本机 Shiny 函数 downloadHandler 因为它在提示用户选择下载目录方面做得非常好。我发现在 downloadHandler.
请注意，在这个 MWE 派生的完整应用程序中，有两个以上的 PNG 文件可供 select 下载。此外，在完整的应用程序中，相同的下载按钮用于单独的 server 部分，此 MWE 中未显示用于下载数据表（效果很好）---因此对象下载的任何更改 selection 需要在 server 部分中完成，而 UI 部分中的 downloadButton("download", "Download") 保持不变，因为它处理的不仅仅是此 MWE 中显示的这些 PNG 文件（我想这意味着某种 renderUI...).
MWE 代码：
library(shiny)
library(shinyMatrix)
library(shinyjs)
library(DT)
matrix1.input <- function(x){
matrixInput(x,
value = matrix(c(0.2), 2, 1, dimnames = list(c("A","B"),NULL)),
rows = list(extend = FALSE, names = TRUE),
cols = list(extend = FALSE, names = FALSE, editableNames = FALSE),
class = "numeric")}
matrix2.input <- 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")}
matrix.validate <- 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)}
vector.base <- function(x,y){
a <- rep(y,x)
b <- seq(1:x)
c <- data.frame(x = b, y = a)
return(c)}
vector.multi <- 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))$y
b <- seq(1:x)
c <- data.frame(x = b, z = a)
return(c)}
vector.multiFinal <- function(x,y){
vector.multi(x,matrix.validate(x,y)[,1],matrix.validate(x,y)[,2])}
matrix.link <- function(x,y){
observeEvent(input$periods|input$base_input,{
updateMatrixInput(session,x,value=matrix(c(input$periods,y),1,2,dimnames=list(NULL, c("y","z"))))})}
ui <-
pageWithSidebar(
headerPanel("Model"),
sidebarPanel(uiOutput("Panels")),
mainPanel(
tabsetPanel(
tabPanel("Dynamic", value=2,
actionButton('showVectorPlotBtn','Vector plots'),
actionButton('showVectorValueBtn','Vector values'),
downloadButton("download", "Download"),
uiOutput("vectorTable")),
id = "tabselected")
) # close main panel
) # close page with sidebar
server <- function(input,output,session)({
periods <- reactive(input$periods)
base_input <- reactive(input$base_input)
vector1_input <- reactive(input$vector1_input)
vector2_input <- reactive(input$vector2_input)
yld <- reactiveValues()
vectorVariable <- function(x,y){
if(input$showVectorBtn == 0) vector.base(input$periods,x)
else vector.multiFinal(input$periods,matrix.validate(input$periods,y))}
output$Panels <- renderUI({
tagList(
conditionalPanel(
condition="input.tabselected==2",
sliderInput('periods','',min=1,max=120,value=60),
matrix1.input("base_input"),
useShinyjs(),
actionButton('showVectorBtn','Show'),
actionButton('hideVectorBtn','Hide'),
actionButton('resetVectorBtn','Reset'),
hidden(uiOutput("Vectors"))))})
renderUI({
matrix.link("vector1_input",input$base_input[1,1])
matrix.link("vector2_input",input$base_input[2,1])})
output$Vectors <- renderUI({input$resetVectorBtn
tagList(matrix2.input("vector1_input",input$periods,input$base_input[1,1]),
matrix2.input("vector2_input",input$periods,input$base_input[2,1]))})
observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
output$graph1 <- renderPlot(plot(vectorVariable(input$base_input[1,1],vector1_input())))
output$graph2 <- renderPlot(plot(vectorVariable(input$base_input[2,1],vector2_input())))
output$download <- downloadHandler(
filename = function() {paste("vector1","png",sep=".")},
content = function(file){
png(file)
plot(vectorVariable(input$base_input[1,1],vector1_input()))
dev.off()}
) # close download handler
output$table1 <- renderDT({vectorsAll()})
observeEvent(input$showVectorPlotBtn,{yld$showme <- tagList(plotOutput("graph1"), plotOutput("graph2"))},ignoreNULL = FALSE)
observeEvent(input$showVectorValueBtn,{yld$showme <- DTOutput("table1")})
output$vectorTable <- renderUI({yld$showme})
vectorsAll <- reactive({
cbind(1:periods(),
vectorVariable(input$base_input[1,1],vector1_input())[,2],
vectorVariable(input$base_input[2,1],vector2_input())[,2])})})
shinyApp(ui, server)
为了回应 ismirsehregal 的评论，下面是使用 actionButton 的工作 MWE，它触发一个带有 selectInput 和下载按钮的模态插入到所述模态中。这是来自 ismirsehregal 的干净解决方案。
MWE 代码（为简洁起见，省略了原始 MWE 中的库和函数定义；如果您想 运行 下面的 MWE，请确保从上面复制库和定义的函数！ !):
ui <-
pageWithSidebar(
headerPanel("Model"),
sidebarPanel(uiOutput("Panels")),
mainPanel(
tabsetPanel(
tabPanel("Dynamic", value=2,
actionButton('showVectorPlotBtn','Vector plots'),
actionButton('showVectorValueBtn','Vector values'),
actionButton("showDownload", "Download"),
uiOutput("vectorTable")),
id = "tabselected")
) # close main panel
) # close page with sidebar
server <- function(input,output,session)({
periods <- reactive(input$periods)
base_input <- reactive(input$base_input)
vector1_input <- reactive(input$vector1_input)
vector2_input <- reactive(input$vector2_input)
yld <- reactiveValues()
vectorVariable <- function(x,y){
if(input$showVectorBtn == 0) vector.base(input$periods,x)
else vector.multiFinal(input$periods,matrix.validate(input$periods,y))}
output$Panels <- renderUI({
tagList(
conditionalPanel(
condition="input.tabselected==2",
sliderInput('periods','',min=1,max=120,value=60),
matrix1.input("base_input"),
useShinyjs(),
actionButton('showVectorBtn','Show'),
actionButton('hideVectorBtn','Hide'),
actionButton('resetVectorBtn','Reset'),
hidden(uiOutput("Vectors"))))})
renderUI({
matrix.link("vector1_input",input$base_input[1,1])
matrix.link("vector2_input",input$base_input[2,1])})
output$Vectors <- renderUI({input$resetVectorBtn
tagList(matrix2.input("vector1_input",input$periods,input$base_input[1,1]),
matrix2.input("vector2_input",input$periods,input$base_input[2,1]))})
observeEvent(input$showVectorBtn,{shinyjs::show("Vectors")})
observeEvent(input$hideVectorBtn,{shinyjs::hide("Vectors")})
output$graph1 <- renderPlot(plot(vectorVariable(input$base_input[1,1],vector1_input())))
output$graph2 <- renderPlot(plot(vectorVariable(input$base_input[2,1],vector2_input())))
output$download <- downloadHandler(
filename = function() {
if (input$downloadItem == "Vector1") {paste("Vector1","png",sep=".")}
else {paste("Vector2","png",sep=".")}
},
content = function(file){
png(file)
if (input$downloadItem == "Vector1"){plot(vectorVariable(input$base_input[1,1],vector1_input()))}
else {plot(vectorVariable(input$base_input[2,1],vector2_input()))}
dev.off()}
) # close download handler
observeEvent(input$showDownload,
{showModal(modalDialog(
selectInput("downloadItem","Select item to download:",
c("Vector1","Vector2")),
downloadButton("download", "Download")
) # close modalDialog
) # close showModal
} # close showModal function
) # close observeEvent
output$table1 <- renderDT({vectorsAll()})
observeEvent(input$showVectorPlotBtn,{yld$showme <- tagList(plotOutput("graph1"), plotOutput("graph2"))},ignoreNULL = FALSE)
observeEvent(input$showVectorValueBtn,{yld$showme <- DTOutput("table1")})
output$vectorTable <- renderUI({yld$showme})
vectorsAll <- reactive({
cbind(1:periods(),
vectorVariable(input$base_input[1,1],vector1_input())[,2],
vectorVariable(input$base_input[2,1],vector2_input())[,2])})})
shinyApp(ui, server)