一旦单击了actionButton,我试图保存从[here] [2]改编的复选框表(see here)中的输入。理想情况下,我想在一个数据帧列中选择一个列表,并将用户名作为行名称。
我尝试使用以下语法,将响应存储在列表中,然后将它们附加到现有的csv.file中。
library(shiny)
library(DT)
answer_options<- c("reading", "swimming",
"cooking", "hiking","binge- watching series",
"other")
question2<- "What hobbies do you have?"
shinyApp(
ui = fluidPage(
h2("Questions"),
p("Below are a number of statements, please indicate your level of agreement"),
DT::dataTableOutput('checkbox_matrix'),
verbatimTextOutput('checkbox_list'),
textInput(inputId = "username", label= "Please enter your username"),
actionButton(inputId= "submit", label= "submit")
),
server = function(input, output, session) {
checkbox_m = matrix(
as.character(answer_options), nrow = length(answer_options), ncol = length(question2), byrow = TRUE,
dimnames = list(answer_options, question2)
)
for (i in seq_len(nrow(checkbox_m))) {
checkbox_m[i, ] = sprintf(
'<input type="checkbox" name="%s" value="%s"/>',
answer_options[i], checkbox_m[i, ]
)
}
checkbox_m
output$checkbox_matrix= DT::renderDataTable(
checkbox_m, escape = FALSE, selection = 'none', server = FALSE,
options = list(dom = 't', paging = FALSE, ordering = FALSE),
callback = JS("table.rows().every(function(i, tab, row) {
var $this = $(this.node());
$this.attr('id', this.data()[0]);
$this.addClass('shiny-input-checkbox');
});
Shiny.unbindAll(table.table().node());
Shiny.bindAll(table.table().node());")
)
observeEvent(input$submit,{
# unlist values from json table
listed_responses <- sapply(answer_options, function(i) input[[i]])
write.table(listed_responses,
file = "responses.csv",
append= TRUE, sep= ',',
col.names = TRUE)
})
}
)
我得到的只是警告:
write.table(listed_responses,file =“responses.csv”,append = TRUE,:将列名附加到文件
除了警告之外,.csv文件中没有保存任何内容,我不确定我到底错过了什么。
如何正确保存数据表中的复选框列表?
答案 0 :(得分:2)
错误来自在col.names = TRUE
的同一次调用中使用append = TRUE
和write.table
。例如:
write.table(mtcars, "test.csv", append = TRUE, sep = ",", col.names = TRUE)
# Warning message:
# In write.table(mtcars, "test.csv", append = TRUE, sep = ",", col.names = TRUE) :
# appending column names to file
write.table
希望您知道它在您的csv中添加了一行列名。由于您可能不希望在每组答案之间添加一行列名,因此在append = TRUE
时仅使用col.names = FALSE
可能更为清晰。您可以使用if...else
编写两种不同的表单来保存您的csv,一种用于创建文件,另一种用于附加后续响应:
if(!file.exists("responses.csv")) {
write.table(responses,
"responses.csv",
col.names = TRUE,
append = FALSE,
sep = ",")
} else {
write.table(responses,
"responses.csv",
col.names = FALSE,
append = TRUE,
sep = ",")
}
您的csv为空白是因为您的复选框未正确绑定为输入。我们可以通过将这些行添加到您的应用中来看到这一点:
server = function(input, output, session) {
...
output$print <- renderPrint({
reactiveValuesToList(input)
})
}
ui = fluidPage(
...
verbatimTextOutput("print")
)
您应用中的哪个lists all of the inputs:
input
中未列出复选框。因此listed_responses
将包含NULL
值列表,而write.table
将保存带有空行的csv。
我没有查看为什么你的js不起作用,但yihui's method用复选框制作数据表似乎运作良好:
# taken from https://github.com/rstudio/DT/issues/93/#issuecomment-111001538
# a) function to create inputs
shinyInput <- function(FUN, ids, ...) {
inputs <- NULL
inputs <- sapply(ids, function(x) {
inputs[x] <- as.character(FUN(inputId = x, label = NULL, ...))
})
inputs
}
# b) create dataframe with the checkboxes
df <- data.frame(
Activity = answer_options,
Enjoy = shinyInput(checkboxInput, answer_options),
stringsAsFactors = FALSE
)
# c) create the datatable
output$checkbox_table <- DT::renderDataTable(
df,
server = FALSE, escape = FALSE, selection = 'none',
rownames = FALSE,
options = list(
dom = 't', paging = FALSE, ordering = FALSE,
preDrawCallback = JS('function() { Shiny.unbindAll(this.api().table().node()); }'),
drawCallback = JS('function() { Shiny.bindAll(this.api().table().node()); } ')
)
)
以下是两个修补程序的示例。我还添加了模式,以便在用户成功提交表单或他们错过用户名时提醒用户。我在提交表格后将其清除。
library(shiny)
library(DT)
shinyApp(
ui =
fluidPage(
# style modals
tags$style(
HTML(
".error {
background-color: red;
color: white;
}
.success {
background-color: green;
color: white;
}"
)),
h2("Questions"),
p("Please check if you enjoy the activity"),
DT::dataTableOutput('checkbox_table'),
br(),
textInput(inputId = "username", label= "Please enter your username"),
actionButton(inputId = "submit", label= "Submit Form")
),
server = function(input, output, session) {
# create vector of activities
answer_options <- c("reading",
"swimming",
"cooking",
"hiking",
"binge-watching series",
"other")
### 1. create a datatable with checkboxes ###
# taken from https://github.com/rstudio/DT/issues/93/#issuecomment-111001538
# a) function to create inputs
shinyInput <- function(FUN, ids, ...) {
inputs <- NULL
inputs <- sapply(ids, function(x) {
inputs[x] <- as.character(FUN(inputId = x, label = NULL, ...))
})
inputs
}
# b) create dataframe with the checkboxes
df <- data.frame(
Activity = answer_options,
Enjoy = shinyInput(checkboxInput, answer_options),
stringsAsFactors = FALSE
)
# c) create the datatable
output$checkbox_table <- DT::renderDataTable(
df,
server = FALSE, escape = FALSE, selection = 'none',
rownames = FALSE,
options = list(
dom = 't', paging = FALSE, ordering = FALSE,
preDrawCallback = JS('function() { Shiny.unbindAll(this.api().table().node()); }'),
drawCallback = JS('function() { Shiny.bindAll(this.api().table().node()); } ')
)
)
### 2. save rows when user hits submit -- either to new or existing csv ###
observeEvent(input$submit, {
# if user has not put in a username, don't add rows and show modal instead
if(input$username == "") {
showModal(modalDialog(
"Please enter your username first",
easyClose = TRUE,
footer = NULL,
class = "error"
))
} else {
responses <- data.frame(user = input$username,
activity = answer_options,
enjoy = sapply(answer_options, function(i) input[[i]], USE.NAMES = FALSE))
# if file doesn't exist in current wd, col.names = TRUE + append = FALSE
# if file does exist in current wd, col.names = FALSE + append = TRUE
if(!file.exists("responses.csv")) {
write.table(responses, "responses.csv",
col.names = TRUE,
row.names = FALSE,
append = FALSE,
sep = ",")
} else {
write.table(responses, "responses.csv",
col.names = FALSE,
row.names = FALSE,
append = TRUE,
sep = ",")
}
# tell user form was successfully submitted
showModal(modalDialog("Successfully submitted",
easyClose = TRUE,
footer = NULL,
class = "success"))
# reset all checkboxes and username
sapply(answer_options, function(x) updateCheckboxInput(session, x, value = FALSE))
updateTextInput(session, "username", value = "")
}
})
}
)