title: Text colour does not match legend using geom_text in ggplot2
body: <p>I have two dataframes, and plotting the first one as a facetted grid of pie charts works fine: </p>
  
  <pre><code>pie_grid &lt;- ggplot(my_dat, aes(x = factor(""), y = value, fill = variable)) + 
     geom_bar(stat = "identity") +       # bar plot
     facet_grid(Cation ~ Anion) +        # grid
     coord_polar(theta = "y") +          # pie chart by converting to polar coord
     scale_x_discrete("") +              # no x-axis label
     scale_y_continuous("")
  </code></pre>
  
  <p>￼<img src="https://i.stack.imgur.com/3J5VU.png" alt="Just one dataframe without labels"></p>
  
  <p>Where <code>my_dat$variable</code> is a column of factors and decides the colour, the grid has <code>Cation</code> as the rows and <code>Anion</code> as the columns. This graph has a legend that  The problem begins when I try to add in text labels using <code>geom_text</code>. I want these numbers in the centre, </p>
  
  <pre><code>pie_grid &lt;- pie_grid + geom_text( aes(x = 0, y = 0, size = 4,
                 label = formatC(round(value, digits =2), format = 'f', digits = 2)), 
                 data = tot.E.dat,
                 show_guide = FALSE,
                 hjust = 0, vjust = 1)
  </code></pre>
  
  <p>The data comes from another dataframe called <code>tot.E.dat</code>, and basically I want a number in the centre of each facet. The result looks like this:
  <img src="https://i.stack.imgur.com/nHztz.png" alt="Added the label data frame"> </p>
  
  <p>As you can see, it does what I want, but there is a slight hiccup. I don't mind that the pies have become donuts, but I do mind that the legend now has a "Total_EFP_Energy", and that doesn't match in colour with the text. How can I get the colour of the numbers to match the legend? If not, how can I get rid of that entry in the legend?</p>
  
  <p>Thank you.</p>
  
  <p>Here is some data (I don't think you want all the rows). The first one is <code>my_dat</code></p>
  
  <pre><code>   Cation  Anion        variable        value
  1     im    bf4    Electrostatic -388.8225640
  2     im     br    Electrostatic -440.0319478
  3     im     cl    Electrostatic -462.6507643
  4     im    dca    Electrostatic -387.0396472
  5     im    mes    Electrostatic -434.2880350
  ...
  17    im    bf4        Repulsion   79.0755418
  18    im     br        Repulsion  180.1054541
  19    im     cl        Repulsion  181.7249981
  20    im    dca        Repulsion  105.0390379
  21    im    mes        Repulsion  112.6103998
  ...
  74   pyr     br  Charge_Transfer    0.5827333
  75   pyr     cl  Charge_Transfer    0.3390909
  76   pyr    dca  Charge_Transfer   -0.9314203
  77   pyr    mes  Charge_Transfer   -2.2744731
  78   pyr   ntf2  Charge_Transfer   -1.0463488
  79   pyr    pf6  Charge_Transfer   -1.6858646
  80   pyr    tos  Charge_Transfer   -2.0899762
  </code></pre>
  
  <p>And also <code>tot.E.dat</code>:</p>
  
  <pre><code>   Cation  Anion         variable     value
  1     im    bf4  Total_EFP_Energy -405.5935
  2     im     br  Total_EFP_Energy -382.3632
  3     im     cl  Total_EFP_Energy -407.9164
  4     im    dca  Total_EFP_Energy -399.4065
  5     im    mes  Total_EFP_Energy -463.8081
  6     im   ntf2  Total_EFP_Energy -380.7301
  7     im    pf6  Total_EFP_Energy -376.5059
  8     im    tos  Total_EFP_Energy -498.7680
  9    pyr    bf4  Total_EFP_Energy -375.3014
  10   pyr     br  Total_EFP_Energy -373.2262
  11   pyr     cl  Total_EFP_Energy -404.0563
  12   pyr    dca  Total_EFP_Energy -366.3844
  13   pyr    mes  Total_EFP_Energy -428.7498
  14   pyr   ntf2  Total_EFP_Energy -341.2173
  15   pyr    pf6  Total_EFP_Energy -353.0248
  16   pyr    tos  Total_EFP_Energy -419.7708
  </code></pre>