AutocompleteInput does not work with param

[MarcSkovMadsen]

Panel: 0.9.5
bokeh: 2.0.2

I was trying to help a user on Discourse get the AutocompleteInput working with panel.Param and param.ObjectSelector on discourse https://discourse.holoviz.org/t/how-to-map-param-string-to-pn-widgets-autocompleteinput/914/2 but could not.

I believe there is a bug

Code

import panel as pn
import param

OBJECTS = ["China", "Thailand", "Japan"]


class App(param.Parameterized):
    string_value = param.ObjectSelector(default="China", objects=OBJECTS)

    view = param.Parameter()

    def __init__(self, **params):
        params["view"] = pn.Param(
            self,
            parameters=["string_value"],
            widgets={"string_value": pn.widgets.AutocompleteInput,},
        )
        super().__init__(**params)


App().view.servable()

Stack Trace

$ python -m panel serve 'scripts\issues\issue_autocomplete.py' --dev --show
2020-07-02 05:25:54,690 Starting Bokeh server version 2.0.2 (running on Tornado 6.0.4)
2020-07-02 05:25:54,691 User authentication hooks NOT provided (default user enabled)
2020-07-02 05:25:54,694 Bokeh app running at: http://localhost:5006/issue_autocomplete
2020-07-02 05:25:54,694 Starting Bokeh server with process id: 22920
2020-07-02 05:25:58,453 Error running application handler <bokeh.application.handlers.script.ScriptHandler object at 0x000001E1F7842648>: List 'options' must be a list.
File "__init__.py", line 1376, in _validate:
raise ValueError("List '%s' must be a list."%(self.name)) Traceback (most recent
call last):
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\bokeh\application\handlers\code_runner.py", line 197, in run
    exec(self._code, module.__dict__)
  File "C:\repos\private\awesome-panel\scripts\issues\issue_autocomplete.py", line 21, in <module>
    App().view.servable()
  File "C:\repos\private\awesome-panel\scripts\issues\issue_autocomplete.py", line 16, in __init__
    widgets={"string_value": pn.widgets.AutocompleteInput,},
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\param.py", line 177, in __init__
    self._update_widgets()
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\param.py", line 234, in _update_widgets
    self._widgets = self._get_widgets()
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\param.py", line 494, in _get_widgets
    widgets += [(pname, self.widget(pname)) for pname in self._ordered_params]
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\param.py", line 494, in <listcomp>
    widgets += [(pname, self.widget(pname)) for pname in self._ordered_params]
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\param.py", line 364, in widget
    widget = widget_class(**kwargs)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\widgets\base.py", line 60, in __init__
    super(Widget, self).__init__(**params)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\viewable.py", line 749, in __init__
    super(Reactive, self).__init__(**params)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\viewable.py", line 358, in __init__
    super(Viewable, self).__init__(**params)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\panel\viewable.py", line 214, in __init__
    super(Layoutable, self).__init__(**params)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\param\parameterized.py", line 2339, in __init__
    self.param._setup_params(**params)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\param\parameterized.py", line 991, in override_initializationtion                                   w)
    fn(parameterized_instance,*args,**k.venv\lib\site-packages\param\parameterizew)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\param\parameter.venv\lib\site-packages\param\parameterizeized.py", line 1202, in _setup_params
    setattr(self,name,val)
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\param\parameterize.venv\lib\site-packages\param\parameterized.py", line 296, in _f
    return f(self, obj, val)           .venv\lib\site-packages\param\__init__.py"
  File "C:\repos\private\awesome-panel\.venv\lib\site-packages\param\parameter a list."%(self.name))ized.py", line 823, in __set__         st.
    self._validate(val)
  File "C:\repos\private\awesome-panel\ction opened.venv\lib\site-packages\param\__init__.n createdpy", line 1376, in _validate
    raise ValueError("List '%s' must be a list."%(self.name))
ValueError: List 'options' must be a list.

[slamer59]

I also need this nice feature inside a class.
I investigate it:

• AutoComplete is a Widget calss when I expected SingleSelectBase

• param.ObjectSelector gives OrderedDict([('China', 'China'), ('Thailand', 'Thailand'), ('Japan', 'Japan')])}
  when options expect List as said
  

  panel/panel/widgets/select.py

  Line 219 in 203a16c

  options = param.List(default=[])

When forcing options to be a list in AutocompleInput

class AutocompleteInput(Widget):

    min_characters = param.Integer(default=2, doc="""
        The number of characters a user must type before
        completions are presented.""")

    options = param.List(default=[])

    placeholder = param.String(default='')

    value = param.Parameter(default=None)
    
    case_sensitive = param.Boolean(default=True)

    restrict = param.Boolean(default=True)

    _widget_type = _BkAutocompleteInput

    _rename = _AutocompleteInput_rename

    def __init__(self, **params):
        options = params.get('options')
        if isinstance(options, OrderedDict):
            params['options'] = list(params['options'].keys())
        super(AutocompleteInput, self).__init__(**params)

this works:

import panel as pn
import param
pn.extension()
OBJECTS = ["China", "Thailand", "Japan"]

class App(param.Parameterized):
    string_value = param.ObjectSelector(default="China", objects=OBJECTS)

app = App()
pn.Column(
    pn.Param(app, widgets={"string_value": pn.widgets.AutocompleteInput})
 
) 

It is not very clean to do it like this but gives an idea where it fails.

What @MarcSkovMadsen proposed does not work.

I see AutocompleInput similar to Select widgets.

[jbednar]

I agree; AutocompleteInput does seem like it should fit into the Select framework.