shiny学习-2
shiny学习-2
概述
填补上次的更新
正文
添加控件
类似的控件如下
shiny提供了一系列的预置的控件，已经打包好，作为函数
函数名 | 控件 |
|---|---|
actionButton | Action Button |
checkboxGroupInput | A group of check boxes |
checkboxInput | A single check box |
dateInput | A calendar to aid date selection |
dateRangeInput | A pair of calendars for selecting a date range |
fileInput | A file upload control wizard |
helpText | Help text that can be added to an input form |
numericInput | A field to enter numbers |
radioButtons | A set of radio buttons |
selectInput | A box with choices to select from |
sliderInput | A slider bar |
submitButton | A submit button |
textInput | A field to enter text |
使用这些控件需要两个参数，一个参数用来命名，一个参数是label，前一个被用来在程序内传递参数，后一个参数用来显示在用户界面 例子
library(shiny)
# 定义 UI ----
ui <- fluidPage(
titlePanel("Basic widgets"), # app的名字
fluidRow( #构建网格化的控件，与之前的sidebarLayout不同
column(3,#3为各个控件的间隔
h3("Buttons"),#3号字体
actionButton("action", "Action"),# 添加动作按钮
br(),
br(),
submitButton("Submit")),
column(3,
h3("Single checkbox"),
# 单选框
checkboxInput("checkbox", "Choice A", value = TRUE)),
column(3,
# 多选框
checkboxGroupInput("checkGroup",
h3("Checkbox group"),
choices = list("Choice 1" = 1,
"Choice 2" = 2,
"Choice 3" = 3),
selected = 1)),
column(3,
# 日期输入
dateInput("date",
h3("Date input"),
value = "2014-01-01"))
),
# 第二个行控件网格
fluidRow(
column(3,# 日期范围
dateRangeInput("dates", h3("Date range"))),
column(3,#输入文件
fileInput("file", h3("File input"))),
column(3, #文本控件
h3("Help text"),
helpText("Note: help text isn't a true widget,",
"but it provides an easy way to add text to",
"accompany other widgets.")),
column(3, #数字输入
numericInput("num",
h3("Numeric input"),
value = 1))
),
# 第三行控件
fluidRow(
column(3,#单选按钮
radioButtons("radio", h3("Radio buttons"),
choices = list("Choice 1" = 1, "Choice 2" = 2,
"Choice 3" = 3),selected = 1)),
column(3,#选择窗口
selectInput("select", h3("Select box"),
choices = list("Choice 1" = 1, "Choice 2" = 2,
"Choice 3" = 3), selected = 1)),
column(3, #滑动条
sliderInput("slider1", h3("Sliders"),
min = 0, max = 100, value = 50),
sliderInput("slider2", "",
min = 0, max = 100, value = c(25, 75))
),
column(3, #文本输入
textInput("text", h3("Text input"),
value = "Enter text..."))
)
)
# 定义server 代码 ----
# 这里为空
server <- function(input, output) {
}
# 运行app ----
shinyApp(ui = ui, server = server)结果
显示输出
在UI中添加r对象的输出 具体函数如下
Output function | Creates |
|---|---|
dataTableOutput | DataTable |
htmlOutput | raw HTML |
imageOutput | image |
plotOutput | plot |
tableOutput | table |
textOutput | text |
uiOutput | raw HTML |
verbatimTextOutput | text |
输出函数需要放在ui的sidebarPanel或mainPanel中 例子
# 构建输出面板，编写UI
ui <- fluidPage(
titlePanel("censusVis"),
sidebarLayout(
sidebarPanel(# 侧面板
helpText("Create demographic maps with
information from the 2010 US Census."),
selectInput("var",
label = "Choose a variable to display",
choices = c("Percent White",
"Percent Black",
"Percent Hispanic",
"Percent Asian"),
selected = "Percent White"),
sliderInput("range",
label = "Range of interest:",
min = 0, max = 100, value = c(0, 100))
),
mainPanel(# 主面板
textOutput("selected_var")#文本输出
)
)
)在面板中定义了输出，接下来需要在server中定义输出内容 在shiny中提供了函数自动引用面板中的数据，render函数自动引用面板中的变量
render function | creates |
|---|---|
renderDataTable | DataTable |
renderImage | images (saved as a link to a source file) |
renderPlot | plots |
renderPrint | any printed output |
renderTable | data frame, matrix, other table like structures |
renderText | character strings |
renderUI | a Shiny tag object or HTML |
# 编写server代码
server <- function(input, output) {
#在ui中，我们定义了selected_var，但是并没有定义它的具体赋值
output$selected_var <- renderText({
paste("You have selected", input$var)
})
}结果，控件框中输入不同的值，右边显示不同的结果
结束语
love & peace