具有HTML UI的Shiny R中下拉菜单的动态选项 [英] Dynamic Options For Dropdown Menu in Shiny R With HTML UI

问题描述

我正在尝试按照 http ://shiny.rstudio.com/articles/html-ui.html 我不确定如何将ui.r中的以下代码转换为HTML.

I'm trying to convert a ui.r into an HTML ui in Shiny following http://shiny.rstudio.com/articles/html-ui.html I'm not sure how to translate the following code from my ui.r into HTML.

我有一个使用以下代码的下拉列表

I have a dropdown that uses the following code

selectInput("data","Choose A Section:", choices=Sections[,2])

下拉菜单中的输入是根据服务器上加载的section变量生成的. section变量可能会不时更改.

The inputs in the dropdown are generated based on a sections variable that is loaded on my server. The sections variable may change from time to time.

我知道我可以粘贴所有部分并创建示例ui中使用的下拉菜单

I know I could paste in all of the sections and create a dropdown used in the example ui http://rstudio.github.io/shiny/tutorial/#html-ui

<label>Sections:</label><br />
    <select name="dist">
      <option value="Section1">Section1</option>
      <option value="Section2">Section2</option>
      <option value="Section3">Section3</option>
      <option value="Section4">Section4</option>
    </select> 

但是我不确定如何为数据更改而可能会更改的选项设置它.是否有捷径可寻?

But I'm not sure how to set it up for options that may change if the data changes. Is there an easy way to do this?

推荐答案

虽然这不是最佳答案，但它可能会让您入门.在Shiny中，我上传了.csv文件，该文件将使用已上传文件的标题名称动态更新下拉菜单.

While this isn't the best answer, it may get you started. In Shiny, I upload .csv files, which will dynamically update the dropdown menu with the header names of the uploaded files.

在server.R中，我包含

observe({

infile <- input$datfile

print(infile)
if(is.null(infile))
  return(NULL)

d <- read.csv(infile$datapath, header = T)

updateSelectInput(session, 'dropdown_1', choices = names(d))
updateSelectInput(session, 'dropdown_2', choices = names(d))

})

在ui.R中，我包括

selectInput('dropdown_1', '', ''),
selectInput('dropdown_2', '', '')

只要您可以指向数据源，我就认为逻辑应该成立.例如，这将在data_set的column1字段中获取唯一项.

As long as you can point to a data source, I'm thinking the logic should hold. For instance, this would grab the unique items in the field named column1 of data_set.

observe({

 data_set <- xxxxx
 updateSelectInput(session, 'dropdown_menu', choices = unique(data_set$column1))

})

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