Bokeh: How to un-select all the values from multi-select drop down list?

Question

I have a MultiSelect drop-down list in Bokeh application. I want to un-select all the values after my work is done.

Answer 1

And the same can also be done with "select all".

from bokeh.io import show
from bokeh.models import CustomJS, MultiChoice, Button

output_file("multichoice-all-clear.html", title="states")

OPTIONS = ["foo", "bar", "baz", "quux"]

## Define the widgets 
buttonAll = Button(label="Select all", button_type="success")
buttonClear = Button(label="Clear selection", button_type="success")
multi_choice = MultiChoice(value=["foo", "baz"], options=OPTIONS)


## Define callbacks/interactivity
multi_choice.js_on_change("value", CustomJS(code="""
    console.log('multi_choice: value=' + this.value, this.toString())
"""))

button_callback = CustomJS(
    args=dict(s=multi_choice),
    code="""
    s.value= s.options;
    console.log('button: click!', this.toString());
    """)
buttonAll.js_on_click(button_callback)


button_callback = CustomJS(
    args=dict(s=multi_choice),
    code="""
    s.value= [];
    console.log('button: click!', this.toString());
    """)
buttonClear.js_on_click(button_callback)



layout = gridplot([buttonAll, buttonClear,
                   multi_choice], ncols=1, toolbar_location=None)

show(layout)

How it looks like

Answer 2

There is no UI interaction the widget itself offers as far as I know to clear it. You could make a button with a CustomJS callback that resets the MultiSelect values:

select = MultiSelect(options=["First", "Second", "Third"])
button = Button(label="clear")

callback = CustomJS(args=dict(s=select), code="s.value=[]")
button.js_on_event('button_click', callback)

Before clicking the button:

After clicking the button: