在 Shiny 中单击 "Reset" 按钮后，我无法引入新的 NumericInputs

Question

我用 Shiny 写了一个应用程序，如果你点击“查看图表”，你可以看到一个直方图。

另一方面，您有 2 个 NumericInputs，您可以在其中更改 x 轴的最小值和最大值。事实上，如果您更改这些值并再次单击“查看绘图”，您将看到 x 轴已更改。

但是，我想要一个按钮来重置值并恢复原始图。有效。

问题是，如果您尝试更改最小值和最大值以再次执行该过程（在您单击“重置”按钮之后），您将无法成功。这些数字已被自动删除，您无法更改这些值，除非您关闭应用程序并再次打开它。

也许代码太复杂，无法绘制单个直方图，但它是原始代码的简单代码。

谁能帮我解决这个问题？

非常感谢。

我的代码：

library(shiny)
library(ggplot2)

################### DATA ########################
val <- c(2.1490626,3.7928443,2.2035281,1.5927854,3.1399245,2.3967338,3.7915825,4.6691277,3.0727319,2.9230937,2.6239759,3.7664386,4.0160378,1.2500835,4.7648343,0.0000000,5.6740227,2.7510256,3.0709322,2.7998003,4.0809085,2.5178086,5.9713330,2.7779843,3.6724801,4.2648527,3.6841084,2.5597235,3.8477471,2.6587736,2.2742209,4.5862788,6.1989269,4.1167091,3.1769325,4.2404515,5.3627032,4.1576810,4.3387921,1.4024381,0.0000000,4.3999099,3.4381837,4.8269218,2.6308474,5.3481382,4.9549753,4.5389650,1.3002293,2.8648220,2.4015338,2.0962332,2.6774765,3.0581759,2.5786137,5.0539080,3.8545796,4.3429043,4.2233248,2.0434363,4.5980727)
df1 <- data.frame(val)
df1$type <- "Type 1"

val <- c(3.7691229,3.6478055,0.5435826,1.9665861,3.0802654,1.2248374,1.7311236,2.2492826,2.2365337,1.5726119,2.0147144,2.3550348,1.9527204,3.3689502,1.7847986,3.5901329,1.6833872,3.4240479,1.8372175,0.0000000,2.5701453,3.6551315,4.0327091,3.8781182)
df2 <- data.frame(val)
df2$type <- "Type 2"

df3 <- rbind(df1, df2)


################ SHINY APP ########################
ui <- fluidPage(
  
  titlePanel("Histogram"),
  
  sidebarLayout(
    sidebarPanel(
      numericInput("xmin", "Min", value=NULL),
      numericInput("xmax", "Max", value=NULL),
      actionButton("reset", "Reset the x-axis"),
      actionButton("add_plot", "See the plot")
      
    ),
    
    mainPanel(
      plotOutput("plot"),
    )
  )
)

server <- function(session, input, output) {
  
  histogram_function <- reactive({
    
    hist <- ggplot(df3, aes(val, fill=type)) +
      geom_histogram(position = "identity", colour = "grey40", bins = 10) +
      ggtitle("Here must be a title") +
      xlab("Values") +
      ylab("Frequency") +
      facet_grid(type ~ .) + 
      theme(strip.text.x = element_blank(),
            strip.text.y = element_blank())
    
      hist <- hist + coord_cartesian(xlim=c(input$xmin, input$xmax))
      
      
      return(hist)
    
  })
  
  v <- reactiveValues(plot = NULL)
  
  observeEvent(input$add_plot, {
    v$plot <- histogram_function()
  })
  
  observe({
    if(input$reset >0){
      
      updateNumericInput(session, "xmin", "Min", value=NA)
      updateNumericInput(session, "xmax", "Max", value=NA)
      
      v$plot <- histogram_function()
      updateNumericInput(session, "xmin", "Min", value=NULL)
      updateNumericInput(session, "xmax", "Max", value=NULL)
    }
  })
  
  output$plot <- renderPlot({
    if (is.null(v$plot)) return()
    v$plot
  })
  
  
} 

shinyApp(ui = ui, server = server)

Answer 1

我认为以下内容应该可以完成工作，我真正添加的只是情节重置 v$plot <- NULL 和 observeEvent

的依赖项

library(shiny)
library(ggplot2)

################### DATA ########################
val <- c(2.1490626,3.7928443,2.2035281,1.5927854,3.1399245,2.3967338,3.7915825,4.6691277,3.0727319,2.9230937,2.6239759,3.7664386,4.0160378,1.2500835,4.7648343,0.0000000,5.6740227,2.7510256,3.0709322,2.7998003,4.0809085,2.5178086,5.9713330,2.7779843,3.6724801,4.2648527,3.6841084,2.5597235,3.8477471,2.6587736,2.2742209,4.5862788,6.1989269,4.1167091,3.1769325,4.2404515,5.3627032,4.1576810,4.3387921,1.4024381,0.0000000,4.3999099,3.4381837,4.8269218,2.6308474,5.3481382,4.9549753,4.5389650,1.3002293,2.8648220,2.4015338,2.0962332,2.6774765,3.0581759,2.5786137,5.0539080,3.8545796,4.3429043,4.2233248,2.0434363,4.5980727)
df1 <- data.frame(val)
df1$type <- "Type 1"

val <- c(3.7691229,3.6478055,0.5435826,1.9665861,3.0802654,1.2248374,1.7311236,2.2492826,2.2365337,1.5726119,2.0147144,2.3550348,1.9527204,3.3689502,1.7847986,3.5901329,1.6833872,3.4240479,1.8372175,0.0000000,2.5701453,3.6551315,4.0327091,3.8781182)
df2 <- data.frame(val)
df2$type <- "Type 2"

df3 <- rbind(df1, df2)


################ SHINY APP ########################
ui <- fluidPage(
    
    titlePanel("Histogram"),
    
    sidebarLayout(
        sidebarPanel(
            numericInput("xmin", "Min", value=NULL),
            numericInput("xmax", "Max", value=NULL),
            actionButton("reset", "Reset the x-axis"),
            actionButton("add_plot", "See the plot")
            
        ),
        
        mainPanel(
            plotOutput("plot"),
        )
    )
)

server <- function(session, input, output) {
    
    v <- reactiveValues(plot = NULL)
    
    histogram_function <- reactive({
        
        hist <- ggplot(df3, aes(val, fill=type)) +
            geom_histogram(position = "identity", colour = "grey40", bins = 10) +
            ggtitle("Here must be a title") +
            xlab("Values") +
            ylab("Frequency") +
            facet_grid(type ~ .) + 
            theme(strip.text.x = element_blank(),
                  strip.text.y = element_blank())
        
        hist <- hist + coord_cartesian(xlim=c(input$xmin, input$xmax))
        return(hist)
        
    })
    
    observeEvent(input$add_plot, {
        v$plot <- histogram_function()
    })
    
    observeEvent(input$reset,{
        updateNumericInput(session, "xmin", "Min", value=NA)
        updateNumericInput(session, "xmax", "Max", value=NA)
        v$plot <- NULL
    },ignoreNULL = TRUE,ignoreInit = TRUE)
    
    output$plot <- renderPlot({
        if (is.null(v$plot)) {
            return()
        }
        v$plot
    })
    
    
} 

shinyApp(ui = ui, server = server)

在 Shiny 中单击 "Reset" 按钮后，我无法引入新的 NumericInputs

I cannot introduce new NumericInputs after clicking a "Reset" Button in Shiny

r

ggplot2

shiny

numeric-input

action-button