USAArrests simple R Shiny App

App.R

# Load required packages
library(shiny)
library(ggplot2)
library(dplyr)

# Adding State column to the original dataset for easy data manipulation at a later stage
states = row.names(USArrests)
crimedata = USArrests %>% 
  mutate("State" = as.factor(states)) # convert State to a factor variable

ui <- fluidPage(
  selectInput(inputId = "state", 
              label = "Select States(s)", 
              choices = levels(crimedata$State),  
              multiple = TRUE,
              selected = levels(crimedata$State)),
  selectInput(inputId = "crime", label = "Select the Crime",
              choices = c("Murder","Assault", "Rape" )),
  actionButton(inputId ="update" , label = "Update & Show Plot"),
  plotOutput("bar")
  
)

server <- function(input, output, session) {
  
  ## Reactive function to subset the data based on the selected states by the user and on click of the button
  s_data <- eventReactive(input$update, 
                          crimedata %>%
                       filter(State %in% input$state))

  
  ## Render plot for the ggplot
  output$bar <- renderPlot({
    p = ggplot(data=s_data(), aes(x=State, y=get(input$crime))) + 
      geom_bar(stat = "identity") +
      xlab("Selected States") +
      ylab(paste(("Selected Crime: "), input$crime)) + 
      ggtitle("States Bar Plot with Crime") +
theme(axis.text.x = element_text(angle = 45, vjust = 0.5, hjust=1))
    
    print(p)
    
  })
  
}

shinyApp(ui, server)