我正在构建一个闪亮的应用程序，它基本上传多个形状文件（dbf，prj，shp，shx）并使用传单包创建地图。上传完成并创建地图后，有一个重置按钮，其功能是清除/重置文件输入的现有值，虽然我尝试使用shinyjs同样做但仍然看起来文件输入缓存值。下面是我试过的代码。寻找休息文件的提示输入如下。
## app.R ##
library(shinydashboard)
library(shinyjs)
library(leaflet)
library(sp)
library(rgdal)
ui <- dashboardPage(
dashboardHeader(title = "Basic dashboard"),
dashboardSidebar(
fileInput('uploadFile', 'Upload Files',
accept=c('text/csv', 'text/comma-separated-values,text/plain'), multiple=T),
fileInput('uploadFile2', 'Upload Files 2',
accept=c('text/csv', 'text/comma-separated-values,text/plain'), multiple=T),
actionButton('reset', 'Reset', icon = icon("minus"),style="color:rgb(57,156,8);border-color:rgb(57,156,8)"),
tags$style(type='text/css', "#reset {margin-left: 10px;}")
),
dashboardBody(
useShinyjs(),
leafletOutput("GeoStates",width = "125%", height = 500)
)
)
server <- function(input, output) {
# Folder name and uploaded file names
values <- reactiveValues(
folderName = "dataSource",
fileName = ""
)
# Expression for reading the OGR and transforming it
expr_q <- quote({
if(values$fileName == "")
return (NULL)
spTransform(readOGR(dsn = paste0(getwd(),"/",values$folderName), layer = values$fileName),
CRS("+proj=longlat +datum=WGS84"))
})
ORG0 <- reactive(expr_q, quoted = TRUE)
# Upload file
observe({
if (!is.null(input$uploadFile)){
hide(id = "uploadMsgBox", anim = TRUE)
if(!dir.exists(values$folderName))
dir.create(values$folderName,recursive = TRUE)
for(i in 1:nrow(input$uploadFile)){
values$fileName <- substr(input$uploadFile[i,1],0,nchar(input$uploadFile[i,1])-4)
file.copy(input$uploadFile[i,4],paste0(getwd(),"/",values$folderName,"/",input$uploadFile[i,1]))
}
}
})
# -------------------------------------------------------------------------------------------------------------------------------
# -------------------------------------------------------------------------------------------------------------------------------
# Folder name and uploaded file names
values2 <- reactiveValues(
folderName2 = "dataSource2",
fileName2 = ""
)
expr_q2 <- quote({
if(values2$fileName2 == "")
return (NULL)
spTransform(readOGR(dsn = paste0(getwd(),"/",values2$folderName2), layer = values2$fileName2),
CRS("+proj=longlat +datum=WGS84"))
})
ORG2 <- reactive(expr_q2, quoted = TRUE)
# Upload file 2
observe({
if (!is.null(input$uploadFile2)){
hide(id = "uploadMsgBox2", anim = TRUE)
if(!dir.exists(values2$folderName2))
dir.create(values2$folderName2,recursive = TRUE)
for(i in 1:nrow(input$uploadFile2)){
values2$fileName2 <- substr(input$uploadFile2[i,1],0,nchar(input$uploadFile2[i,1])-4)
file.copy(input$uploadFile2[i,4],paste0(getwd(),"/",values2$folderName2,"/",input$uploadFile2[i,1]))
}
}
})
#------------------------------------------------------------------------------------------------------------------
#------------------------------------------------------------------------------------------------------------------
observeEvent(input$reset, {
values$fileName == ""
values2$fileName2 == ""
ORG0 <- NULL
ORG2 <- NULL
shinyjs::reset('uploadFile')
shinyjs::reset('uploadFile2')
unlink(paste0(getwd(),"/dataSource"), recursive = TRUE)
unlink(paste0(getwd(),"/dataSource2"), recursive = TRUE)
output$GeoStates <- renderLeaflet({ })
})
#----------------------------------------------------------------------------------------------------------------
#----------------------------------------------------------------------------------------------------------------
observe({
if (!is.null(input$uploadFile) & is.null(input$uploadFile2)){
print("TEST1")
output$GeoStates <- renderLeaflet({
leaflet(data = ORG0()) %>% addTiles() %>% addPolygons(fill = FALSE, stroke = TRUE, color = "#0090C5") %>%
addLegend("bottomright", colors = "#0090C5", labels = values$fileName) %>%
addProviderTiles(providers$Esri.WorldImagery,
options = providerTileOptions(noWrap = TRUE))%>%
addScaleBar(position = "topright", options = scaleBarOptions(metric = TRUE))
})
}
if (!is.null(input$uploadFile) & !is.null(input$uploadFile2)){
print("TEST2")
output$GeoStates <- renderLeaflet({
leaflet(data = ORG0()) %>% addTiles() %>% addPolygons(fill = FALSE, stroke = TRUE, color = "#0090C5") %>%
addLegend("bottomright", colors = "#0090C5", labels = values$fileName) %>%
addProviderTiles(providers$Esri.WorldImagery,
options = providerTileOptions(noWrap = TRUE))%>%
addPolygons(fill = FALSE, stroke = TRUE, color = "#F39200", data = ORG2())%>%
addScaleBar(position = "topright", options = scaleBarOptions(metric = TRUE))
})
}
})
}
shinyApp(ui, server)