add options to include shapes and newshape in legends

[archmoj]

Resolves #98 ! 😎
@plotly/plotly_js
@chriddyp

[alexcjohnson]

Can we say something about unranked or equal rank items? I presume traces according to their order in data, then shapes according to their order in layout.shapes?

Also I don't see shapes[].legendrank used in a test image to intersperse shapes and traces, or shapes[].legend to put shapes on multiple legends, can we add those?

[archmoj]

Good call.
Addressed in 2e77fc7, 58b1cb1 and 3168078.

[LiamConnors]

@archmoj, trying this out with Plotly.py, if i set itemclick to toggleothers on the legend, with a graph with three traces and two shapes, when I click on a trace, it only toggles the other two traces.

And if I click on a shape, it only toggles the three traces, not the other shape

import plotly.graph_objects as go

fig = go.Figure()

fig.add_trace(go.Scatter(
    x=[1, 2, 3, 4, 5],
    y=[1, 2, 3, 4, 5],
    mode='markers',
    marker={'size':50}
))

fig.add_trace(go.Scatter(
    x=[1, 2, 3, 4, 5],
    y=[5, 4, 3, 2, 1],
    mode='markers',
    marker={'size':25}
))

fig.add_shape(
    showlegend=True,
    type="line",
    x0=3,
    y0=0.5,
    x1=5,
    y1=0.8,
    line_width=3,
    label=dict(texttemplate="Slope: %{slope:.3f}", font=dict(size=20)),
)


fig.add_shape(
    showlegend=True,
    type="rect",
    fillcolor="yellow",
    x0=1.5,
    y0=2.5,
    x1=5,
    y1=5.5,
    line_width=3,
    label=dict(
        texttemplate="Width: %{width:.3f}",
        font=dict(family="Courier New, monospace", size=20),
    ),
)

fig.add_trace(go.Scatter(
    x=[1, 2, 3, 4, 5],
    y=[5, 4, 3, 2, 1],
    mode='markers',
    marker={'size':25}
))

fig.update_layout(legend= {'itemclick': 'toggleothers'})

fig.show()

Also, the shapes always appear after the traces in the legend, even if I define them first. How is the legendrank supposed to work by default if I don't set it for a particular trace/shape?
I would have thought they'd appear in the order defined.

[archmoj]

@LiamConnors Thanks for your feedback.
I made various improvements in this PR as well as what included in v2.24.3.
I appreciate it if you could possibly QA this PR again. 🙏

Regarding your question about shapes being presented at the end of traces, if one wants shapes to be displayed first, they could e.g. set legendrank: 1 in each trace. I also improved the legendrank documentation in this regards. Please let me know if you have any suggestions.

Thank you!

[LiamConnors]

Thanks @archmoj! That update to the description makes sense and I'll add an example to the docs that shows this. I still encounter the issue when itemclick is set to toggleothers.

[alexcjohnson]

I notice a bug that seems to be new in this PR: if you have multiple legends, with or without shapes, you can double-click a trace or shape to isolate it, but if you double-click the same trace or shape again it doesn't bring the others back.

[alexcjohnson]

You fixed my last comment in #6684 so this is good to go after the conflict is resolved! Nice work! 💃