Reactive plot is mapping variable name? - r

Question

I'm trying to create an reactive plot where you can select an ethnicity in a selectInput() and see the population of that ethnicity in the midwest.
This is my ui:
ethnicity_sidebar_content <- sidebarPanel(
selectInput(
inputId = "ethnicity",
label = "Select Ethnicity",
choices = list(
"Total" = "total",
"White" = "white",
"Black" = "black",
"American Indian" = "amerindian",
"Asian" = "asian",
"Other" = "other"
)
)
)
ethnicity_main_content <- mainPanel(
plotOutput("ethnicity_plot")
)
ethnicity_panel <- tabPanel(
"Midwest by Ethnicity",
sidebarLayout(
ethnicity_sidebar_content,
ethnicity_main_content
)
)
This is my server:
midwest_poverty <- midwest %>%
mutate(popbelowpoverty = floor(percbelowpoverty / 100 * poppovertyknown)) %>%
group_by(state) %>%
summarise(
poppovertyknown = sum(poppovertyknown),
popbelowpoverty = sum(popbelowpoverty)
) %>%
mutate(popabovepoverty = poppovertyknown - popbelowpoverty)
server <- function(input, output) {
output$ethnicity_plot <- renderPlot({
p <- ggplot(data = midwest_ethnicity) +
geom_bar(
mapping = aes(x = state, y = input$ethnicity),
stat = "identity"
)
p
})
}
When I run shinyApp, I keep getting a bar plot that graphs the column name rather than the data in the column.
Edit: I think this was a simple mistake where I was using aes instead of aes_string

Answer 1

When you write aes(x = state, y = input$ethnicity) in the ggplot call, it will look for variable state in the dataset midwest_ethnicity for x-axis. Same for y, it will look for a variable named White for instance if this is the value in input$ethnicity.
I don't think there is a variable with such a name in your dataset.
If it is the case (White is a variable of your dataset), it could not work if ggplot don't consider input$ethnicity as a string, and not as a value. You can test y = get(input$ethnicity).
Another option as proposed in comments, is to use aes_string() instead of aes().