如何根据另一个变量更改 Leaflet Shiny app 圆圈颜色？

Question

我是 Shiny 的新手。我正在尝试用竞争对手药房的积分和我的药房（Tim's pharmacies）的积分制作一个图层。我希望积分的颜色不同（比赛为红色，我的为绿色）。我想我需要从 leaflet() 中删除 pharmacy 并创建一个新的观察事件，但无法使其正常工作。有两个数据集：第一个是竞争对手药店，第二个是我的。我将它们与 rbind 结合起来，并认为我可以根据二进制编码的my_store 列指定颜色（我的为 1，竞争为 0）？任何帮助将不胜感激。

ID	Label	Lat	Long	State
1	Bob's	47.14032	-107.334	Montana
2	Bob's	44.57247	-116.125	Montana
3	Evan's	42.88031	-111.989	Idaho
4	Evan's	42.93041	-112.3654	Idaho
5	Silvia's	42.19124	-112.7645	Idaho
6	Evan's	45.7939	-108.768	Montana
7	John's	46.71677	-106.752	Wyoming

ID	Label	Lat	Long	State
1	Tim's	47.22632	-107.774	Montana
2	Tim's	44.67257	-116.135	Montana
3	Tim's	42.88031	-111.779	Idaho
4	Tim's	42.89041	-112.3324	Idaho
5	Tim's	42.19124	-112.7645	Idaho
6	Tim's	45.8539	-108.658	Montana
7	Tim's	46.72887	-106.7542	Wyoming

library(shiny)
library(leaflet)
library(dplyr)
library(leaflet.extras)
# install.packages("leaflet.extras")

pharmacy <- read_excel("~/pharmacy.xlsx")
My_Pharmacy <- read_excel("~/My_Pharmacy.xlsx")

all_stores <- rbind(pharmacy, My_Pharmacy)
all_stores <-
    all_stores %>%
    mutate(my_store = if_else(Label == "Tim's Pharmacy",1,0))

# Define UI 
ui <- fluidPage(

    # Application title
    titlePanel("map"),

 

        # Show a map output
        mainPanel(
           leafletOutput(outputId = "map_pharmacy"),
           selectInput(inputId = "State",
                       label = "choose a store brand",
                       choices = unique(pharmacy$State))
        )
    )


# Define server logic required 
server <- function(input, output, session) {
    filteredData <- reactive({
        pharmacy %>%
            filter(State == input$State)
    })

    output$map_pharmacy <- renderLeaflet({
        leaflet(pharmacy) %>% addTiles() %>%
            fitBounds(~min(Long), ~min(Lat), ~max(Long), ~max(Lat))
        })
    
    
    observe({
    leafletProxy("map_pharmacy", data = filteredData()) %>%
        clearShapes() %>%
        addCircles(color = "red", weight = 10)
    })
}

# Run the application 
shinyApp(ui = ui, server = server)```

Answer 1

我会创建一个调色板pal 用于addCircles 的颜色。

您可能希望colorFactor 根据您的二元因素（我的药房或不是我的药房）着色。

您可以使用预定义的调色板（请参阅RColorBrewer::display.brewer.all() 了解可用的不同调色板）。或者，您可以定义自己并专门为每个因子级别选择颜色。

这是完整的例子：

library(shiny)
library(leaflet)

pharmacy$my_store <- 0
My_Pharmacy$my_store <- 1

all_stores <- rbind(pharmacy, My_Pharmacy)

pal <- colorFactor(
  # Use a predefined palette:
  # palette = "Dark2",
  # 
  # Or specify individual colors:
  palette = c("purple", "orange"),
  domain = all_stores$my_store
)

ui <- fluidPage(
  titlePanel("map"),
  mainPanel(
    leafletOutput(outputId = "map_pharmacy"),
    selectInput(inputId = "State",
                label = "choose a store brand",
                choices = unique(all_stores$State))
  )
)

server <- function(input, output, session) {
  
  filteredData <- reactive({
    all_stores %>%
      filter(State == input$State)
  })
  
  output$map_pharmacy <- renderLeaflet({
    leaflet(filteredData()) %>% 
      addTiles() %>%
      fitBounds(~min(Long), ~min(Lat), ~max(Long), ~max(Lat))
  })
  
  observe({
    leafletProxy("map_pharmacy", data = filteredData()) %>%
      clearShapes() %>%
      addCircles(color = ~pal(my_store),
                 lng = ~Long,
                 lat = ~Lat,
                 weight = 10)
  })

}

shinyApp(ui = ui, server = server)