Source code for panel.layout.tabs

Layout component to lay out objects in a set of tabs.
from __future__ import annotations

from collections import defaultdict
from typing import (
    TYPE_CHECKING, ClassVar, List, Mapping, Type,

import param

from bokeh.models import Spacer as BkSpacer, TabPanel as BkTabPanel

from ..models.tabs import Tabs as BkTabs
from ..viewable import Layoutable
from .base import NamedListPanel

    from bokeh.model import Model

[docs]class Tabs(NamedListPanel): """ The `Tabs` layout allows switching between multiple objects by clicking on the corresponding tab header. Tab labels may be defined explicitly as part of a tuple or will be inferred from the `name` parameter of the tab’s contents. Like `Column` and `Row`, `Tabs` has a list-like API with methods to `append`, `extend`, `clear`, `insert`, `pop`, `remove` and `__setitem__`, which make it possible to interactively update and modify the tabs. Reference: :Example: >>> pn.Tabs(('Scatter', plot1), some_pane_with_a_name) """ closable = param.Boolean(default=False, doc=""" Whether it should be possible to close tabs.""") dynamic = param.Boolean(default=False, doc=""" Dynamically populate only the active tab.""") tabs_location = param.ObjectSelector( default='above', objects=['above', 'below', 'left', 'right'], doc=""" The location of the tabs relative to the tab contents.""") height = param.Integer(default=None, bounds=(0, None)) width = param.Integer(default=None, bounds=(0, None)) _bokeh_model: ClassVar[Type[Model]] = BkTabs _direction: ClassVar[str | None] = 'vertical' _js_transforms: ClassVar[Mapping[str, str]] = {'tabs': """ var ids = []; for (var t of value) {{ ids.push( }}; var value = ids; """} _manual_params: ClassVar[List[str]] = ['closable'] _rename: ClassVar[Mapping[str, str | None]] = { 'closable': None, 'dynamic': None, 'name': None, 'objects': 'tabs' } _source_transforms: ClassVar[Mapping[str, str | None]] = { 'dynamic': None, 'objects': None } def __init__(self, *objects, **params): super().__init__(*objects, **params) self._rendered = defaultdict(dict) = (-1, len(self)-1), ['dynamic', 'active']) def _update_names(self, event): # No active tabs will have a value of -1 = (-1, len( super()._update_names(event) def _cleanup(self, root: Model | None = None) -> None: super()._cleanup(root) if root: if root.ref['id'] in self._panels: del self._panels[root.ref['id']] if root.ref['id'] in self._rendered: del self._rendered[root.ref['id']] @property def _preprocess_params(self): return NamedListPanel._preprocess_params + (['active'] if self.dynamic else []) #---------------------------------------------------------------- # Callback API #---------------------------------------------------------------- def _process_close(self, ref, attr, old, new): """ Handle closed tabs. """ model, _ = self._models.get(ref) if model: try: inds = [old.index(tab) for tab in new] except Exception: return old, None old = self.objects new = [old[i] for i in inds] return old, new def _comm_change(self, doc, ref, comm, subpath, attr, old, new): if attr in self._changing.get(ref, []): self._changing[ref].remove(attr) return if attr == 'tabs': old, new = self._process_close(ref, attr, old, new) if new is None: return super()._comm_change(doc, ref, comm, subpath, attr, old, new) def _server_change(self, doc, ref, subpath, attr, old, new): if attr in self._changing.get(ref, []): self._changing[ref].remove(attr) return if attr == 'tabs': old, new = self._process_close(ref, attr, old, new) if new is None: return super()._server_change(doc, ref, subpath, attr, old, new) def _update_active(self, *events): for event in events: if == 'dynamic' or (self.dynamic and == 'active'): self.param.trigger('objects') return def _compute_sizing_mode(self, children, props): children = [child.child for child in children] return super()._compute_sizing_mode(children, props) #---------------------------------------------------------------- # Model API #---------------------------------------------------------------- def _manual_update(self, events, model, doc, root, parent, comm): for event in events: if == 'closable': for child in model.tabs: child.closable = def _get_objects(self, model, old_objects, doc, root, comm=None): """ Returns new child models for the layout while reusing unchanged models and cleaning up any dropped objects. """ from ..pane.base import RerenderError, panel new_models, old_models = [], [] if len(self._names) != len(self): raise ValueError('Tab names do not match objects, ensure ' 'that the Tabs.objects are not modified ' 'directly. Found %d names, expected %d.' % (len(self._names), len(self))) for i, (name, pane) in enumerate(zip(self._names, self)): pane = panel(pane, name=name) self.objects[i] = pane ref = root.ref['id'] panels = self._panels[ref] rendered = self._rendered[ref] for obj in old_objects: if obj in self.objects: continue obj._cleanup(root) panels.pop(id(obj), None) rendered.pop(id(obj), None) current_objects = list(self) for i, (name, pane) in enumerate(zip(self._names, self)): pref = id(pane) hidden = self.dynamic and i != panel = panels.get(pref) prev_hidden = ( hasattr(panel, 'child') and isinstance(panel.child, BkSpacer) and panel.child.tags == ['hidden'] ) # If object has not changed, we have not toggled between # hidden and unhidden state or the tabs are not # dynamic then reuse the panel if (pane in old_objects and pref in panels and (not (hidden ^ prev_hidden) or not (self.dynamic or prev_hidden))): new_models.append(panel) continue if prev_hidden and not hidden and pref in rendered: child = rendered[pref] old_models.append(child) elif hidden: child = BkSpacer(**{k: v for k, v in pane.param.values().items() if k in Layoutable.param and v is not None and k not in ('name', 'design')}) child.tags = ['hidden'] else: try: rendered[pref] = child = pane._get_model(doc, root, model, comm) except RerenderError as e: if e.layout is not None and e.layout is not self: raise e e.layout = None return self._get_objects(model, current_objects[:i], doc, root, comm) panel = panels[pref] = BkTabPanel( title=name,, child=child, closable=self.closable ) new_models.append(panel) return new_models, old_models