我正致力于在callback应用DataTables应用中为shiny应用DataTables实施DT功能。到目前为止，我对阅读sum this example（第4.4节）的想法是，可以通过columnDefs options参数应用相同的类columnDefs如下所示，但如果我只知道在哪里放置JS参数来手动完成类链接也是有意义的。
您可以删除所有callback和library(shiny)
library(DT)
ui <- fluidPage(
title = 'Select Table Rows',
hr(),
h1('A Server-side Table'),
fluidRow(
column(9, DT::dataTableOutput('x3'))
)
)
server <- function(input, output, session) {
# server-side processing
mtcars2 = mtcars[, 1:8]
output$x3 = DT::renderDataTable(DT::datatable(mtcars2,
extensions = 'Buttons',
options = list(
scrollX = TRUE,
scrollY = TRUE,
pageLength = 10,
order = list(list(1, 'asc')),
fixedHeader = TRUE,
dom = 'Blrtip',
buttons = c('copy', 'csv', 'excel', 'pdf', 'print')
# columnDefs = JS("[
# { className: 'sum', 'targets': [ 1,2 ] }
# ]")
# ),
#callback = JS(
# " function(row, data, start, end, display) {
# var api = this.api();
#
# api.columns('.sum', { page: 'current' }).every(function () {
# var sum = api
# .cells( null, this.index(), { page: 'current'} )
# .render('display')
# .reduce(function (a, b) {
# var x = parseFloat(a) || 0;
# var y = parseFloat(b) || 0;
# return x + y;
# }, 0);
# console.log(this.index() +' '+ sum); //alert(sum);
# $(this.footer()).html(sum);
# });
#}"
)
)
)
}
shinyApp(ui = ui, server = server)
参数，以查看示例起点。
app.R
library(shiny)
library(DT)
ui <- fluidPage(
title = 'Select Table Rows',
hr(),
h1('A Server-side Table'),
fluidRow(
column(9, DT::dataTableOutput('x3'))
)
)
server <- function(input, output, session) {
# server-side processing
mtcars2 = mtcars[, 1:8]
sketch <- htmltools::withTags(table(
class = "display",
style = "bootstrap",
tableHeader(colnames(mtcars2)),
tableFooter(colnames(mtcars2))
))
output$x3 = DT::renderDataTable(DT::datatable(mtcars2,
container = sketch,
extensions = 'Buttons',
options = list(
scrollX = TRUE,
scrollY = TRUE,
pageLength = 10,
order = list(list(1, 'asc')),
dom = 'Blrtip',
buttons = c('copy', 'csv', 'excel', 'pdf', 'print'),
footerCallback = JS(
"function( tfoot, data, start, end, display ) {",
"var api = this.api(), data;",
"total = api.column( 1, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"total1 = api.column( 2, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"total2 = api.column( 3, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"total3 = api.column( 4, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"total4 = api.column( 5, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"total5 = api.column( 6, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"total6 = api.column( 7, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"total7 = api.column( 8, { page: 'current'} ).data().reduce( function ( a, b ) {return a + b;} )",
"$( api.column( 1 ).footer() ).html(total.toFixed(2));
$( api.column( 2 ).footer() ).html(total1.toFixed(2));
$( api.column( 3 ).footer() ).html(total2.toFixed(2));
$( api.column( 4 ).footer() ).html(total3.toFixed(2));
$( api.column( 5 ).footer() ).html(total4.toFixed(2));
$( api.column( 6 ).footer() ).html(total5.toFixed(2));
$( api.column( 7 ).footer() ).html(total6.toFixed(2));
$( api.column( 8 ).footer() ).html(total7.toFixed(2));",
"}"
))
))
}
shinyApp(ui = ui, server = server)
最终解决方案：
list1=[['a'], ['b'], ['c'], ['d']]
list2=[['e'], ['f'], ['g']]
file.csv=
a
b
c
d
e
f
g
我意识到这可能是JS的不良形式，但是，在我的情况下，这最有效，因此我可以对每个应用不同的选项（某些货币符号，某些平均值，不同的小数精度等）。
答案 0 :(得分：2)
为了显示页脚中的总和/总数，您必须在表格中添加一个容器，如下所示。我还更改了JS代码：下面提供的版本必须正常工作。不幸的是，我不知道你的JS代码有什么问题，因为我不是javascript的人。您可以使用HTML（...）部分来更改总和的显示。
server <- function(input, output, session) {
# server-side processing
mtcars2 = mtcars[, 1:8]
sketch = htmltools::withTags(table(tableFooter(c("",0,0,0,0,0,0,0,0))))
output$x3 = DT::renderDataTable(DT::datatable(mtcars2, container = sketch,
extensions = 'Buttons',
options = list(
scrollX = TRUE,
scrollY = TRUE,
pageLength = 10,
order = list(list(1, 'asc')),
fixedHeader = TRUE,
dom = 'Blrtip',
buttons = c('copy', 'csv', 'excel', 'pdf', 'print')
footerCallback = JS(
"function( tfoot, data, start, end, display ) {",
"var api = this.api();",
"$( api.column( 1 ).footer() ).html(",
"api.column( 1).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"$( api.column( 2 ).footer() ).html(",
"api.column( 2 ).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"$( api.column( 3 ).footer() ).html(",
"api.column( 3 ).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"$( api.column( 4 ).footer() ).html(",
"api.column( 4 ).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"$( api.column( 5 ).footer() ).html(",
"api.column( 5 ).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"$( api.column( 6 ).footer() ).html(",
"api.column( 6 ).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"$( api.column( 7 ).footer() ).html(",
"api.column( 7 ).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"$( api.column( 8 ).footer() ).html(",
"api.column( 8 ).data().reduce( function ( a, b ) {",
"return a + b;",
"} )",
");",
"}")
)
)
)
}
答案 1 :(得分：0)
我精心设计了此功能，作为有关总计和格式的可能解决方案。如果需要运行复杂的操作，只需先运行代码，然后将值插入为operation = "custom"。希望对您有所帮助。
library(DT)
dat <- iris[1:4]
sketch <- htmltools::tags$table(
tableHeader(names(dat)),
tableFooter(rep("", ncol(dat))))
js_op <- function(column, operation, name = "", signif = 3) {
# Auxiliar function for mean
aux <- ifelse(
operation == "mean",
paste0("map(function(num) { return num/data.length; })."), "")
# Decimals to consider
signif <- 10^signif
# Operation
if (operation %in% c("sum", "mean"))
operation <- paste0("Math.round((a+b)*",signif,")/",signif)
if (operation == "count")
operation <- "data.length"
if (operation == "custom")
return(paste0("$(api.column(", column, ").footer()).html('", name, "')"))
# Result
res <- paste0(
"$(api.column(", column, ").footer()).html('", name, "'+",
"api.column(", column, ").data().", aux, "reduce( function ( a, b ) {",
"return ", operation, ";",
"} ));")
return(res)
}
javascript <- JS(
"function(tfoot, data, start, end, display ) {",
"var api = this.api(), data;",
js_op(0, operation = "count", name = "Counter: "),
js_op(1, operation = "sum", name = "Sum: "),
js_op(2, operation = "mean", name = "Mean: "),
js_op(3, operation = "custom", name = "Something"),
";}")
datatable(iris[,1:4], rownames = FALSE, container = sketch,
options = list(footerCallback = javascript))