Manually define a color key



Combine two layers into a plot, and set a custom color of one layer. Add a manual color key with labels that match the two layers. (Note that "deepskyblue" is the default color for Geom.line and others.)

points = DataFrame(index=rand(0:10,30), val=rand(1:10,30))
line = DataFrame(val=rand(1:10,11), index = [0:10])
pointLayer = layer(points, x="index", y="val", Geom.point,Theme(default_color=colorant"green"))
lineLayer = layer(line, x="index", y="val", Geom.line)
plot(pointLayer, lineLayer, Guide.manual_color_key("Legend", ["Points", "Line"], ["green", "deepskyblue"]))