Nsryjdtyk

I am attempting to leverage ggplot code found on SO. The problem is i keep getting errors and i think it has something to do with trying to pass the the functions through shinydashboard. I've tried all sorts of things. I can get this to render fine in the console but not in shinydashboard.

 library(shinydashboard)

 library(shiny)

 library(ggplot2)

 library(dplyr)



 ui <- fluidPage(

   gggauge(52,breaks=c(0,35,70,100)

 )



 )

 server <- function(input, output) {

   gggauge <- function(pos,breaks=c(0,30,70,100)) {

     get.poly <- function(a,b,r1=0.5,r2=1.0) {

       th.start <- pi*(1-a/100)

       th.end <- pi*(1-b/100)

       th <- seq(th.start,th.end,length=100)

       x <- c(r1*cos(th),rev(r2*cos(th)))

       y <- c(r1*sin(th),rev(r2*sin(th)))

       return(data.frame(x,y))

     }

     ggplot()+ 

      geom_polygon(data=get.poly(breaks[1],breaks[2]),aes(x,y),fill="red")+

      geom_polygon(data=get.poly(breaks[2],breaks[3]),aes(x,y),fill="gold")+geom_polygon(data=get.poly(breaks[3],breaks[4]),aes(x,y),fill="forestgreen")+

      geom_polygon(data=get.poly(pos-1,pos+1,0.2),aes(x,y))+

      geom_text(data=as.data.frame(breaks), size=5, fontface="bold", vjust=0,

        aes(x=1.1*cos(pi*(1-breaks/100)),y=1.1*sin(pi*(1-breaks/100)),label=paste0(breaks,"%")))+

      annotate("text",x=0,y=0,label=pos,vjust=0,size=8,fontface="bold")+

      coord_fixed()+

      theme_bw()+

      theme(axis.text=element_blank(),

        axis.title=element_blank(),

        axis.ticks=element_blank(),

        panel.grid=element_blank(),

        panel.border=element_blank()) 

   }

 }

 shinyApp(ui = ui, server = server)

Use -

library(shinydashboard)

library(shiny)

library(ggplot2)

library(dplyr)



gggauge <- function(pos,breaks=c(0,30,70,100)) {

  get.poly <- function(a,b,r1=0.5,r2=1.0) {

    th.start <- pi*(1-a/100)

    th.end <- pi*(1-b/100)

    th <- seq(th.start,th.end,length=100)

    x <- c(r1*cos(th),rev(r2*cos(th)))

    y <- c(r1*sin(th),rev(r2*sin(th)))

    return(data.frame(x,y))

  }

  ggplot()+ 

    geom_polygon(data=get.poly(breaks[1],breaks[2]),aes(x,y),fill="red")+

    geom_polygon(data=get.poly(breaks[2],breaks[3]),aes(x,y),fill="gold")+geom_polygon(data=get.poly(breaks[3],breaks[4]),aes(x,y),fill="forestgreen")+

    geom_polygon(data=get.poly(pos-1,pos+1,0.2),aes(x,y))+

    geom_text(data=as.data.frame(breaks), size=5, fontface="bold", vjust=0,

              aes(x=1.1*cos(pi*(1-breaks/100)),y=1.1*sin(pi*(1-breaks/100)),label=paste0(breaks,"%")))+

    annotate("text",x=0,y=0,label=pos,vjust=0,size=8,fontface="bold")+

    coord_fixed()+

    theme_bw()+

    theme(axis.text=element_blank(),

          axis.title=element_blank(),

          axis.ticks=element_blank(),

          panel.grid=element_blank(),

          panel.border=element_blank()) 

}



ui <- fluidPage(



  plotOutput("plot1", click = "plot_click"),

  verbatimTextOutput("info")



)



server <- function(input, output) {



  output$plot1 <- renderPlot({

    #plot(mtcars$wt, mtcars$mpg)

    gggauge(52,breaks=c(0,35,70,100))

  })

}

shinyApp(ui = ui, server = server)

Output

Explanation

You mixed up a few things but you were almost there. Everything you need is right here. You just need to organize. Let's go through the components -

1. 
   gggauge is a function that renders the plot, so it needs to be a function defined separately and called from the server component. Merely defining it in the server object was not enough. In your case the function was getting defined, not called!


2. The ui component needs a placeholder for rendering a plot. Directly trying to render the plot in ui won't cut it. You just need an plotOutput object there which acts as a placeholder (a UI component)


3. Now that (1) and (2) are taken care of, its time to render the plot in the server object by calling the gggauge function.

Hop that helps!