R 在许多被动对象中使用if语句';行不通
我想使用我的R 在许多被动对象中使用if语句';行不通,r,shiny,shiny-reactivity,R,Shiny,Shiny Reactivity,我想使用我的currentvariable5()reactive对象创建某种类型的绘图if==“A”(if(currentvariable5()==“A”){})和另一个if==“B”(else{})。但我在几篇文章中尝试了许多技巧,结果总是: Warning: Error in : Operation not allowed without an active reactive context. * You tried to do something that can only be done
currentvariable5()
reactive对象创建某种类型的绘图if==“A”(if(currentvariable5()==“A”){}
)和另一个if==“B”(else{}
)。但我在几篇文章中尝试了许多技巧,结果总是:
Warning: Error in : Operation not allowed without an active reactive context.
* You tried to do something that can only be done from inside a reactive consumer.
55: <Anonymous>
Error : Operation not allowed without an active reactive context.
* You tried to do something that can only be done from inside a reactive consumer.
警告:错误:在没有活动-反应上下文的情况下,不允许操作。
*您试图做一些只能从被动消费者内部完成的事情。
55:
错误:如果没有活动-反应上下文,则不允许操作。
*您试图做一些只能从被动消费者内部完成的事情。
这是我的例子:
library(leaflet)
library(leaflet.providers)
library(ggplot2)
library(shinythemes)
library(sf)
library(lubridate)
library(dplyr)
library(rgdal)
# get AOI
download.file(
"https://github.com/Leprechault/trash/raw/main/stands_example.zip",
zip_path <- tempfile(fileext = ".zip")
)
unzip(zip_path, exdir = tempdir())
# Open the files
setwd(tempdir())
stands_extent <- readOGR(".", "stands_target") # Border
stands_ds <- read.csv("pred_target_stands.csv", sep=";") # Data set
stands_ds <- stands_ds %>%
mutate(DATA_S2 = ymd(DATA_S2))
stands_ds$CLASS<-c(rep("A",129),rep("B",130))
stands_ds$CD<-abs(rnorm(length(stands_ds[,1]),mean=50))
# Create the shiny dash
ui <- fluidPage(
theme = shinytheme("cosmo"),
titlePanel(title="My Map Dashboard"),
sidebarLayout(
sidebarPanel(
selectInput(inputId = "selectedvariable0",
label = "Type",
choices = c(unique(stands_ds$PEST)),selected = TRUE ),
selectInput(inputId = "selectedvariable1",
label = "Date",
choices = c(unique(stands_ds$DATA_S)),selected = TRUE ),
selectInput(inputId = "selectedvariable2",
label = "Project",
choices = c(unique(stands_ds$PROJETO)),selected = TRUE ),
selectInput(inputId = "selectedvariable3",
label = "Stand",
choices = c(unique(stands_ds$CD_TALHAO)),selected = TRUE),
selectInput(inputId = "selectedvariable4",
label = "Unique ID",
choices = c(unique(stands_ds$ID_UNIQUE)),selected = TRUE),
selectInput(inputId = "selectedvariable5",
label = "Class",
choices = c(unique(stands_ds$CLASS)),selected = TRUE)
),
mainPanel(
textOutput("idSaida"),
fluidRow(
splitLayout(plotOutput("myplot"))),
dateInput(inputId = "Dates selection", label = "Time"),
leafletOutput("map")
)
)
)
server <- function(input, output){
currentvariable0 <- reactive({input$selectedvariable0})
currentvariable1 <- reactive({input$selectedvariable1})
currentvariable2 <- reactive({input$selectedvariable2})
currentvariable3 <- reactive({input$selectedvariable3})
currentvariable4 <- reactive({input$selectedvariable4})
currentvariable5 <- reactive({input$selectedvariable5})
if(currentvariable5()=="A"){
output$myplot <- renderPlot({
#Subset stand
stands_sel <- subset(stands_extent, stands_extent@data$ID_UNIQUE==currentvariable4())
#Subset for input$var and assign this subset to new object, "fbar"
ds_sel<- stands_ds[stands_ds$ID_UNIQUE==currentvariable4(),]
#Create a map
polys <- st_as_sf(stands_sel)
ggplot() +
geom_sf(data=polys) +
geom_point(data=ds_sel,
aes(x=X, y=Y), color="red") +
xlab("Longitude") + ylab("Latitude") +
coord_sf() +
theme_bw() +
theme(text = element_text(size=10))
})
} else {
#Subset stand
stands_sel <- subset(stands_extent, stands_extent@data$ID_UNIQUE==currentvariable4())
#Subset for input$var and assign this subset to new object, "fbar"
ds_sel<- stands_ds[stands_ds$ID_UNIQUE==currentvariable4(),]
#Create a map
polys <- st_as_sf(stands_sel)
ggplot() +
geom_sf(data=polys) +
geom_raster(data = stands_sel, aes(x = X, y = Y, fill = CD)) +
scale_fill_gradientn(name="Desfolha (%)",colours = terrain.colors(100))+
xlab("Longitude") + ylab("Latitude") +
coord_sf() +
theme_bw() +
theme(text = element_text(size=10))
}
output$map <- renderLeaflet({
stands_actual<-stands_ds[stands_ds$ID_UNIQUE==currentvariable4(),]
lng <- mean(stands_actual$X)
lat <- mean(stands_actual$Y)
leaflet() %>%
setView(lng = lng, lat = lat, zoom=17) %>%
addProviderTiles(providers$Esri.WorldImagery) %>%
addMarkers(lng=stands_actual$X, lat=stands_actual$Y, popup="Location")
})
}
shinyApp(ui, server)
##
图书馆(传单)
图书馆(传单供应商)
图书馆(GG2)
图书馆(shinythemes)
图书馆(sf)
图书馆(lubridate)
图书馆(dplyr)
图书馆(rgdal)
#获取AOI
下载文件(
"https://github.com/Leprechault/trash/raw/main/stands_example.zip",
zip_path我们可以将if-else语句包装在observe
()中。之所以不调用reactive
(),是因为我们实际上对这里的副作用感兴趣(例如声明输出$myplot。另外,一个reactive(observe,reactive,eventReactive observeEvent)每当调用输入$..时,建议使用上下文,因为它将根据用户的输入进行更改
library(leaflet)
library(leaflet.providers)
library(ggplot2)
library(shinythemes)
library(sf)
library(lubridate)
library(dplyr)
library(rgdal)
library(rgeos)
# get AOI
download.file(
"https://github.com/Leprechault/trash/raw/main/stands_example.zip",
zip_path <- tempfile(fileext = ".zip")
)
unzip(zip_path, exdir = tempdir())
# Open the files
setwd(tempdir())
stands_extent <- readOGR(".", "stands_target") # Border
stands_ds <- read.csv("pred_target_stands.csv", sep=";") # Data set
stands_ds <- stands_ds %>%
mutate(DATA_S2 = ymd(DATA_S2))
stands_ds$CLASS<-c(rep("A",129),rep("B",130))
stands_ds$CD<-abs(rnorm(length(stands_ds[,1]),mean=50))
# Create the shiny dash
ui <- fluidPage(
theme = shinytheme("cosmo"),
titlePanel(title="My Map Dashboard"),
sidebarLayout(
sidebarPanel(
selectInput(inputId = "selectedvariable0",
label = "Type",
choices = c(unique(stands_ds$PEST)),selected = TRUE ),
selectInput(inputId = "selectedvariable1",
label = "Date",
choices = c(unique(stands_ds$DATA_S)),selected = TRUE ),
selectInput(inputId = "selectedvariable2",
label = "Project",
choices = c(unique(stands_ds$PROJETO)),selected = TRUE ),
selectInput(inputId = "selectedvariable3",
label = "Stand",
choices = c(unique(stands_ds$CD_TALHAO)),selected = TRUE),
selectInput(inputId = "selectedvariable4",
label = "Unique ID",
choices = c(unique(stands_ds$ID_UNIQUE)),selected = TRUE),
selectInput(inputId = "selectedvariable5",
label = "Class",
choices = c(unique(stands_ds$CLASS)),selected = TRUE)
),
mainPanel(
textOutput("idSaida"),
fluidRow(
splitLayout(plotOutput("myplot"))),
dateInput(inputId = "Dates selection", label = "Time"),
leafletOutput("map")
)
)
)
server <- function(input, output){
currentvariable0 <- reactive({input$selectedvariable0})
currentvariable1 <- reactive({input$selectedvariable1})
currentvariable2 <- reactive({input$selectedvariable2})
currentvariable3 <- reactive({input$selectedvariable3})
currentvariable4 <- reactive({input$selectedvariable4})
currentvariable5 <- reactive({input$selectedvariable5})
observe({
if(currentvariable5()=="A"){
output$myplot <- renderPlot({
#Subset stand
stands_sel <- subset(stands_extent, stands_extent@data$ID_UNIQUE==currentvariable4())
#Subset for input$var and assign this subset to new object, "fbar"
ds_sel<- stands_ds[stands_ds$ID_UNIQUE==currentvariable4(),]
#Create a map
polys <- st_as_sf(stands_sel)
ggplot() +
geom_sf(data=polys) +
geom_point(data=ds_sel,
aes(x=X, y=Y), color="red") +
xlab("Longitude") + ylab("Latitude") +
coord_sf() +
theme_bw() +
theme(text = element_text(size=10))
})
} else {
#Subset stand
stands_sel <- subset(stands_extent, stands_extent@data$ID_UNIQUE==currentvariable4())
#Subset for input$var and assign this subset to new object, "fbar"
ds_sel<- stands_ds[stands_ds$ID_UNIQUE==currentvariable4(),]
#Create a map
polys <- st_as_sf(stands_sel)
ggplot() +
geom_sf(data=polys) +
geom_raster(data = stands_sel, aes(x = X, y = Y, fill = CD)) +
scale_fill_gradientn(name="Desfolha (%)",colours = terrain.colors(100))+
xlab("Longitude") + ylab("Latitude") +
coord_sf() +
theme_bw() +
theme(text = element_text(size=10))
}
output$map <- renderLeaflet({
stands_actual<-stands_ds[stands_ds$ID_UNIQUE==currentvariable4(),]
lng <- mean(stands_actual$X)
lat <- mean(stands_actual$Y)
leaflet() %>%
setView(lng = lng, lat = lat, zoom=17) %>%
addProviderTiles(providers$Esri.WorldImagery) %>%
addMarkers(lng=stands_actual$X, lat=stands_actual$Y, popup="Location")
}) }) #end of observe function.
}
shinyApp(ui, server)
图书馆(传单)
图书馆(传单供应商)
图书馆(GG2)
图书馆(shinythemes)
图书馆(sf)
图书馆(lubridate)
图书馆(dplyr)
图书馆(rgdal)
图书馆(rgeos)
#获取AOI
下载文件(
"https://github.com/Leprechault/trash/raw/main/stands_example.zip",
zip\u路径您希望何时运行if(currentvariable5()==“A”)
检查?现在这不在反应上下文中。您正在尝试更改绘图吗?那么它应该在renderPlot()
块中。不清楚否则意味着什么。