python - Show text annotations on selection in Bokeh -

i have little bokeh plot data points , associated text labels. want text labels appear when user selects points box select tool. gets me close:

from bokeh.plotting import columndatasource,figure,show  source = columndatasource(     data=dict(         x=test[:,0],         y=test[:,1],         label=[unquote_plus(vocab_idx[i]) in range(len(test))]))  tools="box_zoom,pan,reset,box_select" p = figure(plot_width=400, plot_height=400,tools=tools) p.circle(x='x',y='y', size=10, color="red", alpha=0.25,source=source)  renderer = p.text(x='x',y='y',text='label',source=source)  renderer.nonselection_glyph.text_alpha=0.  show(p) 

this close, in if draw box around points, text labels shown , rest hidden, problem renders text labels start (which not want). initial plot should have labels hidden, , should appear upon box_select.

i thought start rendering alpha=0.0, , setting selection_glyph parameter, this:

... renderer = p.text(x='x',y='y',text='label',source=source,alpha=0.) renderer.nonselection_glyph.text_alpha=0. renderer.selection_glyph.text_alpha=1. ... 

but throws error:

attributeerror: 'nonetype' object has no attribute 'text_alpha' 

when trying access text_alpha attribute of selection_glyph.

i know use hover effect here or similar, need labels default not being visible. alternative, not ideal, solution have toggle button switches labels on , off, i'm not sure how either.

what doing wrong here?

as of version 0.11.1, value of selection_glyph none default. interpreted bokehjs "don't different, draw glyph normal". need create selection_glyph. there 2 ways this, both demonstrated here:

http://bokeh.pydata.org/en/latest/docs/user_guide/styling.html#selected-and-unselected-glyphs

basically, are

by hand

create actual circle bokeh model, like:

selected_circle = circle(fill_alpha=1, fill_color="firebrick", line_color=none) renderer.selection_glyph = selected_circle 

or

using glyph method parameters

alternatively, convenience figure.circle accepts paramters selection_fill_alpha or selection_color (basically line or fill or text property, prefixed selection_) :

p.circle(..., selection_color="firebrick") 

then circle created automatically , used renderer.selection_glyph

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i hope useful information. if so, highlights there 2 possible ways project improved:

• updating docs explicit , highlight renderer.selection_glyph none default

• changing code renderer.selection_glyph copy of renderer.glyph default (then original code work)

either small in scope , ideal new contributor. if interested in working pull request either of these tasks, (and other users) grateful contribution. in case, please make issue first @

https://github.com/bokeh/bokeh/issues

that references discussion, , can provide more details or answer questions.