Change variable names into variable labels and remove legend title

Question

I created a function to produce ggplot choropleth maps, and it works:) However, I would like to remove the legend title (see picture below), since it now says 'I'. Furthermore, I would like to change the hover text into the variable labels as adapted in the Maps dataframe. However, when I merge this datafile with the shape file, en furthermore turn the MAPS dataframe into a readable format for ggplot, the variable labels are lost in the process. So, I would like to maintain the variable labels, and also want to incorporate the variable labels somehow in my function code, so I get the variable label of the fill= variable in my ggplotly hover text.

Below my code:

library(shiny)
library(shinydashboard)
library(ggplot2)
library(cbsodataR)
library(plotly)
library(sjlabelled)
library(expss)
library(tidyr)
library(tidyverse)
library(dplyr)
library(stringr)
library(rgdal)
library(plyr)

#Loading shapefile
ShapefileWijken <- readOGR("/Users/anne/Desktop/RondeVenen/ALGEMEEN_DATA/SHAPEFILES_DRV_6PC_5PC_Gemeente/WijkenEnBuurten/WijkenEnBuurten.shp")
#Opening data Dutch public database
Maps <- cbs_get_data("84583NED", 
                   select=c("AantalInwoners_5","HuishoudensTotaal_28", 
                              "Woningvoorraad_34", "GemiddeldInkomenPerInkomensontvanger_65", "Codering_3"))
#Merge data with shapefile
MAPS <- merge(ShapefileWijken, 
              Maps, 
              by.x = "BU_CODE", 
              by.y="Codering_3", 
              all=FALSE)
#Turn data into readable format for ggplot
MAPS@data$id <- rownames(MAPS@data)
TUSSEN <- fortify(MAPS, region="id")
CHOROPLETH <- merge(TUSSEN, MAPS@data, by="id")
library(plyr)
CHOROPLETH <- join(TUSSEN, MAPS@data, by="id")

###FUNCTION MAPS
ggplot_MAP <- function(i){
  ggplot(data = CHOROPLETH, aes(x=long, y=lat, group = group)) +
    geom_polygon(aes(fill=i), color="black")  +
    scale_fill_gradient(low="#99cc33", high="#009999") +
    theme_void() + 
    theme(panel.border = element_blank(), panel.grid.major = element_blank(),
          panel.grid.minor = element_blank(), axis.line.y=element_blank(), axis.line.x=element_blank(), 
          legend.title = element_blank())
}

#Adding gg plot choropleth map to shiny server 
output$MAPINWONERS <- renderPlotly({
    ggplotly(ggplot_MAP(CHOROPLETH$AantalInwoners_5)) %>% config(modeBarButtonsToRemove = c(
      'sendDataToCloud', 'autoScale2d', 'resetScale2d', 'toggleSpikelines',
      'hoverClosestCartesian', 'hoverCompareCartesian',
      'zoom2d','pan2d','select2d','lasso2d','zoomIn2d','zoomOut2d'
    ), displaylogo=FALSE) %>% layout(dragmode=FALSE) 

Answer 1

You can remove legend title by adding labs(fill=NULL) immediately after your geom_polygon() statement. To get the desired hover text, define text=paste("Text1",var1,"\nText2",var2) inside the aes of ggplot ; here Text1 and Text2 will be your desired text, and var1 and var2 will be your variable labels. Then include tooltip=c("text") in ggplotly .