How can I activate/ deactivate a HoverTool with a bokeh button widget?

Question

I am trying to link a HoverTool to a Toggle Button in bokeh. I want to generate a stand alone dashboard as an html so I would like to use some cutom javascript to toggle the hovertool using a toggle button.

Here is some sample code:

from bokeh.plotting import ColumnDataSource, figure, output_file, show
from bokeh.layouts import row
from bokeh.models import Toggle, CustomJS

output_file("toolbar.html")

source = ColumnDataSource(
    data=dict(x=[1, 2, 3, 4, 5], y=[2, 5, 8, 2, 7], desc=["A", "b", "C", "d", "E"],)
)

TOOLTIPS = [
    ("index", "$index"),
    ("(x,y)", "($x, $y)"),
    ("desc", "@desc"),
]

p = figure(
    plot_width=400, plot_height=400, tooltips=TOOLTIPS, title="Mouse over the dots"
)

p.circle("x", "y", size=20, source=source)

# I would like to have some js code activate and deactivate the Hovertool
# and delete the option for the hovertool from the plots sidebar
button = Toggle(label="HoverTool", button_type="success")


show(row(p, button))

Answer 1

As of Bokeh 2.0.1, dynamically adding/removing tools from the toolbar is not supported. You can activate/deactivate the tool this way:

button = Toggle(label="HoverTool", button_type="success", active=True)

cb = CustomJS(args=dict(button=button, hover=p.hover[0]), code="""
hover.active = button.active
""")

button.js_on_click(cb)

Answer 2

To complement bigreddot's answer, you can also add

p.toolbar_location = None

It will completely remove the toolbar though, not just the HoverTool button. The HoverTool can still be toggle with the button.