Disappearing Toolbar

In the example below (the plot appears after the button is pressed), the toolbar disappears when the plot (or toolbar) is tapped. The problem appeared in 0.12.11 onwards.

Software versions… Bokeh 0.12.13 Python 3.5.2 Firefox 57.0.4 (64 bit)

from bokeh.models.sources import ColumnDataSource
from bokeh.models.layouts import Column, WidgetBox
from bokeh.models.widgets import Button, Div
from bokeh.plotting import Figure
from bokeh.io import curdoc
from bokeh.events import Tap

fig = Figure()
line_src = ColumnDataSource(data={'x': [0, 1], 'y': [0, 1]})
line = fig.line('x', 'y', source=line_src)


def update_data(event):
    line_src.data['x'][1] = event.x
    line_src.data['y'][1] = event.y
    fig.renderers.remove(line)
    fig.renderers.append(line)

fig.on_event(Tap, update_data)


def update_plot():
    gui.children[1] = fig

btn = Button(label='Click to plot')
btn.on_click(update_plot)
gui = Column(WidgetBox(btn), Div())

curdoc().add_root(gui)

[marcuskd]

Just re-ran the original example from the 1.1.0 dev2 build and it works fine, many thanks to the dev team for the continuing great work!

[mattpap]

The problem here is a result of toolbar panel being created in bokehjs and added to Plot.renderers, which isn’t synchronized properly between browser and server, so when line glyph is updated, bokehjs attempts to remove the panel and fails with that. The failure allows for rendering a panel that was destroyed, and this results in an exception. This is along standing problem that we allow internal bokehjs objects to interact with the server. Fixing this would likely fix a few dozen other issues.