filter - 从 R Shiny 中的选定输入中过滤

Question

尝试根据所选输入过滤数据库时，我不断收到错误消息。我基于 iris 数据集做了一个非常简单的例子来向你们展示我的问题：

    ```{r}
    library(flexdashboard)
    library(tidyverse)
    ```
    
    Sidebar {.sidebar}
    =====================================
    
    ```{r}
    
    fluidRow(
      column(7,
             selectInput("Species", "Choose a species",
                         choices = c("setosa", "versicolor", "virginica"))))
    
    mydata <- reactive({
    iris %>% filter(Species == input$Species)
    })
    
    ```
    
    Results
    ===================================== 
    
    ```{r}
    head(mydata)
    ```

Answer 1

作为mydata反应式，您必须mydata()在反应式上下文中评估它（例如renderDT）。有关更多信息，请参阅带有闪亮和闪亮教程的flexdashboard。

---
title: "test"
runtime: shiny
output:
  flexdashboard::flex_dashboard:
  orientation: columns
vertical_layout: fill
theme: bootstrap
---
  

    ```{r global, include = FALSE}
    
    library(flexdashboard)
    library(tidyverse)
    library(DT)
    
    ```
    
    Sidebar {.sidebar}
    =====================================
    
    ```{r}
    
    fluidRow(
      column(7,
             selectInput("Species", "Choose a species",
                         choices = c("setosa", "versicolor", "virginica"))))
    
    mydata <- reactive({
    iris %>% filter(Species == input$Species)
    })
    
    ```
    
    Results
    ===================================== 
    
    ```{r}
    renderDT({head(mydata())})
    ```