legend doesn't work with line+symbol plots

[mauro3]

This adds both legends to the black-plot. One to the line, one to the "o". (this is on commit 705449e)

using Winston
plot([1,2], "o-")
oplot([1,3], "o-r")
legend(["black", "red"])

[heliosdrm]

That's an issue related to the structure of the plots in Winston.
plot(x,y,"o-"), etc. actually creates two plot components, one for the line and another for the points; and each one has a different key in the legends.

There is no plot component type (that I am aware of) that may be used to put both components into a single one, and create a mixed legend. It might be created, but it does not exist in this moment.

A workaround is creating two overlapping legends manually:

using Winston
p = plot([1,2], "o-")
oplot([1,3], "o-r")
comp = getcomponents(p)
[setattr(comp[i], label="black") for i=1:2]
[setattr(comp[i], label="red") for i=3:4]
leg1 = Legend(0.1,0.9,{comp[1], comp[3]})
leg2 = Legend(0.1,0.9,{comp[2], comp[4]})
add(p, leg1, leg2)

[heliosdrm]

The creation of combined legends can be done more easily with the type "PlotGroup" that I have added in this fork: https://github.com/heliosdrm/Winston.jl/tree/legend (proposed as pull request #200).

Example:

using Winston
# Assign the plot to variable p to get the list of components
p = plot([1,2], "o-")
oplot([1,3], "o-r")
comp = getcomponents(p)

# use Winston.PlotGroup(components::Array{Any,1}) to group the plot components:
# comp[1:2] contain the black line and points, comp[3:4] the red ones.
# Add these two groups to a new plot p2, and make the legend for them.
p2 = FramedPlot()
add(p2, Winston.PlotGroup(comp[1:2]), Winston.PlotGroup(comp[3:4]))
legend(p2, ["black", "red"])