I have a shiny app which creates a scatter plot between selected variables of the mtcars dataset. As you can see I have modified the data labels in order to display the car type in every point instead of the x-y coordinates. The problem is that when I click on my trendline, on spots where there are no data -so the coordinates are displayed-the app is breaking down. Here is a reproducible example:
#ui.r
library(shiny)
library(ggplot2)
library(plotly)
library(dplyr)
fluidPage(
# App title ----
titlePanel(div("CROSS CORRELATION",style = "color:blue")),
# Sidebar layout with input and output definitions ----
sidebarLayout(
# Sidebar panel for inputs ----
sidebarPanel(
),
# Main panel for displaying outputs ----
mainPanel(
tabsetPanel(type = "tabs",
tabPanel("Correlation Plot",
fluidRow(
column(3, uiOutput("lx1")),
column(3,uiOutput("lx2"))),
hr(),
fluidRow(
tags$style(type="text/css",
".shiny-output-error { visibility: hidden; }",
".shiny-output-error:before { visibility: hidden; }"
)
),
fluidRow(
plotlyOutput("sc"))
)
)
)))
#server.r
function(input, output) {
output$lx1<-renderUI({
selectInput("lx1", label = h4("Select 1st Expression Profile"),
choices = colnames(mtcars[,2:5]),
selected = "Lex1")
})
output$lx2<-renderUI({
selectInput("lx2", label = h4("Select 2nd Expression Profile"),
choices = colnames(mtcars[,2:5]),
selected = "Lex2")
})
# 1. create reactive values
vals <- reactiveValues()
# 2. create df to store clicks
vals$click_all <- data.frame(x = numeric(),
y = numeric(),
label = character())
# 3. add points upon plot click
observe({
# get clicked point
click_data <- event_data("plotly_click", source = "select")
# get data for current point
label_data <- data.frame(x = click_data[["x"]],
y = click_data[["y"]],
label = click_data[["key"]],
stringsAsFactors = FALSE)
# add current point to df of all clicks
vals$click_all <- merge(vals$click_all,
label_data,
all = TRUE)
})
output$sc<-renderPlotly({
mtcars$car <- row.names(mtcars)
p1 <- ggplot(mtcars, aes_string(x = input$lx1, y = input$lx2,key = "car",group="car"))+
# Change the point options in geom_point
geom_point(color = "darkblue") +
# Change the title of the plot (can change axis titles
# in this option as well and add subtitle)
labs(title = "Cross Correlation") +
# Change where the tick marks are
# Change how the text looks for each element
theme_bw()+
geom_smooth(aes(group = 1))+
# 4. add labels for clicked points
geom_text(data = vals$click_all,
aes(x = x, y = y, label = label),
inherit.aes = FALSE, nudge_x = 0.25)
ggplotly(p1,source = "select", tooltip = c("key")) %>%
layout(hoverlabel = list(bgcolor = "white",
font = list(family = "Calibri",
size = 9,
color = "black")))
})
}