title: Adding a legend to a dumbbell chart in R
body: <p>using the following code, I created a dumbbell chart. </p>
  
  <pre><code>f &lt;- ggplot(Brewers_PA, aes(x=PA.2015, xend=PA.2016, y=Name))
  f + geom_dumbbell(colour = "darkblue", point.colour.l = "darkred", point.colour.r = "darkBlue", point.size.l = 2.5, point.size.r = 2.5) + 
    theme(plot.background=element_rect(fill = "grey93", colour = "grey93")) +
    theme(plot.title=element_text(size = 11, face = "bold", hjust = 0)) + 
    theme(axis.text.x=element_text(size = 8)) +
    theme(axis.text.y=element_text(size = 8)) +
    theme(axis.title.x=element_text(size = 9)) + 
    theme(axis.title.y=element_text(size=9)) + ylab("") + xlab("Plate Appearance") + 
    ggtitle("Brewers Change in Plate Appearance 2015-2016") 
  </code></pre>
  
  <p>I was able to do this thanks to this tutorial. <a href="https://www.r-bloggers.com/beating-lollipops-into-dumbbells/" rel="nofollow">https://www.r-bloggers.com/beating-lollipops-into-dumbbells/</a></p>
  
  <p>The only problem is that I would like to add a legend to this but I am not sure how. Does anybody know? All help is appreciated. </p>
  
  <p>I would basically like the legend to show the years to the colours. So, "darkblue" = 2016 (PA.2016), "darkred" = 2015 (PA.2015). I wanted to add a picture but for some reason it won't work.</p>
  
  <p>Here is the data frame I created:</p>
  
  <pre><code>               Name     PA.2015 PA.2016
  1   Jonathan Villar     128     679
  2      Chris Carter     460     644
  3        Ryan Braun     568     564
  4   Scooter Gennett     391     542
  5      Hernan Perez     272     430
  6  Kirk Nieuwenhuis     141     392
  7   Jonathan Lucroy     415     544
  8        Aaron Hill     353     429
  9      Ramon Flores     289     289
  10  Domingo Santana     187     281
  11 Martin Maldonado     256     253
  12     Keon Broxton       2     244
  13    Orlando Arcia       0     216
  </code></pre>
  
  <blockquote>
    <p></p>
  </blockquote>