运行应用程序时出现闪亮错误：match.arg(position) 中的错误：'arg' 必须为 NULL 或字符向量

Question

I keep getting the error "Error in match.arg(position) : 'arg' must be NULL or a character vector" when trying to run my shiny app. I read and reread my code and I can't seem to find an issue. I also have no idea whether this issue is in my ui code or server code. Can anyone spot what I'm missing?

Here's my ui logic:

library(rtweet)
library(tidytext)
library(tidyverse)
library(stringr)
library(shiny)
library(DT)
library(markdown)
library(shinythemes)

source("R_rainclouds.R")


#create variables for ggplot
joined_names_tweets <- read_rds("joined_names_tweets.rds")
tweets <- read_rds("tweets.rds")


ui <- navbarPage("Project",
                 theme = shinytheme("united"),

     ###########
     ###DATA###
     ##########

           tabPanel("Graphics",
                    tabsetPanel(
                      tabPanel("Over Time",
                               sidebarPanel(
                                 selectInput("screen_name", "NCAA Twitter Accounts:",
                                             choices = joined_names_tweets$screen_name),
                                 mainPanel(plotOutput("raincloud")))),
                      tabPanel("Stuff"))),

    #############
    ##EXPLORE###
    ############

           tabPanel("Explore",

                    fluidPage(
                      titlePanel("Explore the data"),

                      sidebarLayout(
                        sidebarPanel(
                          helpText("Pick an NCAA Twitter Account to view recent tweets"),
                          h3("Tweet Search"),
                          selectInput("screen_name", NULL,
                                      choices = tweets$screen_name,
                                      selected = "@NCAA")),
                        mainPanel(
                          DTOutput("word_table")),
    ##########
    ##ABOUT##
    #########
                    tabPanel("About",
                    fluidRow(
                        column(8,
                               includeMarkdown("about.Rmd"))))))))

and here's my server logic:

server <- function(input, output, session) {

  ########
  ##DATA##
  ########

  output$raincloud <- renderPlot({

    data <- joined_names_tweets %>%
      filter(screen_name == input$screen_name) %>% 

      ggplot(aes(x=sex_id,y=created_at, fill = sex_id)) +
      geom_flat_violin(position = position_nudge(x = .2, y = 0),adjust = 4) +
      geom_point(position = position_jitter(width = .15), size = .25, alpha = .5) +
      ylab('Date')+
      xlab('Gender')+
      coord_flip()+
      theme_cowplot()+
      guides(fill = FALSE) +
      scale_fill_manual(values = c("snow1", "steelblue"))
  })


  ############
  ##EXPLORE##
  ###########

  output$word_table <- renderDT({

    datatable(tweets %>% filter(screen_name == input$screen_name) %>% select(-screen_name),
              class = 'display',
              rownames = FALSE,
              selection = 'single',
              colnames = c("Tweet Text", "Date", "Favorites", "Retweets"),
              options = list(dom = 'tip'))
  })

}


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

Answer 1

I believe your issue is in your UI If you notice the sidebarLayout function has four arguments and tabPanel is not of them. You currently have sidebarPanel and mainPanel but then have another tabPanel before closing the sidebarLayout .

If you delete the tabPanel you should be able to get it to work.

You can read a little more on this other question to get a better idea of what I mean.

shiny Error in match.arg(position) : 'arg' must be NULL or a character vector