Current File : //usr/lib/python3/dist-packages/orca/object_navigator.py
# Orca
#
# Copyright 2023 The Orca Team
# Author: Rynhardt Kruger <rynkruger@gmail.com>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., Franklin Street, Fifth Floor,
# Boston MA 02110-1301 USA.
"""Provides ability to navigate objects hierarchically."""
__id__ = "$Id$"
__version__ = "$Revision$"
__date__ = "$Date$"
__copyright__ = "Copyright (c) 2023 The Orca Team"
__license__ = "LGPL"
from . import cmdnames
from . import debug
from . import focus_manager
from . import input_event
from . import keybindings
from . import messages
from .ax_event_synthesizer import AXEventSynthesizer
from .ax_object import AXObject
from .ax_utilities import AXUtilities
class ObjectNavigator:
"""Provides ability to navigate objects hierarchically."""
def __init__(self):
self._navigator_focus = None
self._last_navigator_focus = None
self._last_locus_of_focus = None
self._simplify = True
self._handlers = self.get_handlers(True)
self._bindings = keybindings.KeyBindings()
def get_bindings(self, refresh=False, is_desktop=True):
"""Returns the object-navigator keybindings."""
if refresh:
msg = "OBJECT NAVIGATOR: Refreshing bindings."
debug.printMessage(debug.LEVEL_INFO, msg, True)
self._setup_bindings()
elif self._bindings.isEmpty():
self._setup_bindings()
return self._bindings
def get_handlers(self, refresh=False):
"""Returns the object-navigator handlers."""
if refresh:
msg = "OBJECT NAVIGATOR: Refreshing handlers."
debug.printMessage(debug.LEVEL_INFO, msg, True)
self._setup_handlers()
return self._handlers
def _setup_bindings(self):
"""Sets up the object-navigator key bindings."""
self._bindings = keybindings.KeyBindings()
self._bindings.add(
keybindings.KeyBinding(
"Up",
keybindings.defaultModifierMask,
keybindings.ORCA_CTRL_MODIFIER_MASK,
self._handlers.get("object_navigator_up")))
self._bindings.add(
keybindings.KeyBinding(
"Down",
keybindings.defaultModifierMask,
keybindings.ORCA_CTRL_MODIFIER_MASK,
self._handlers.get("object_navigator_down")))
self._bindings.add(
keybindings.KeyBinding(
"Right",
keybindings.defaultModifierMask,
keybindings.ORCA_CTRL_MODIFIER_MASK,
self._handlers.get("object_navigator_next")))
self._bindings.add(
keybindings.KeyBinding(
"Left",
keybindings.defaultModifierMask,
keybindings.ORCA_CTRL_MODIFIER_MASK,
self._handlers.get("object_navigator_previous")))
self._bindings.add(
keybindings.KeyBinding(
"Return",
keybindings.defaultModifierMask,
keybindings.ORCA_CTRL_MODIFIER_MASK,
self._handlers.get("object_navigator_perform_action")))
self._bindings.add(
keybindings.KeyBinding(
"s",
keybindings.defaultModifierMask,
keybindings.ORCA_CTRL_MODIFIER_MASK,
self._handlers.get("object_navigator_toggle_simplify")))
msg = "OBJECT NAVIGATOR: Bindings set up."
debug.printMessage(debug.LEVEL_INFO, msg, True)
def _setup_handlers(self):
"""Sets up the object-navigator input event handlers."""
self._handlers = {}
self._handlers["object_navigator_up"] = \
input_event.InputEventHandler(
self.up,
cmdnames.NAVIGATOR_UP)
self._handlers["object_navigator_down"] = \
input_event.InputEventHandler(
self.down,
cmdnames.NAVIGATOR_DOWN)
self._handlers["object_navigator_next"] = \
input_event.InputEventHandler(
self.next,
cmdnames.NAVIGATOR_NEXT)
self._handlers["object_navigator_previous"] = \
input_event.InputEventHandler(
self.previous,
cmdnames.NAVIGATOR_PREVIOUS)
self._handlers["object_navigator_perform_action"] = \
input_event.InputEventHandler(
self.perform_action,
cmdnames.NAVIGATOR_PERFORM_ACTION)
self._handlers["object_navigator_toggle_simplify"] = \
input_event.InputEventHandler(
self.toggle_simplify,
cmdnames.NAVIGATOR_TOGGLE_SIMPLIFIED)
msg = "OBJECT NAVIGATOR: Handlers set up."
debug.printMessage(debug.LEVEL_INFO, msg, True)
def _include_in_simple_navigation(self, obj):
"""Returns True if obj should be included in simple navigation."""
return AXUtilities.is_paragraph(obj)
def _exclude_from_simple_navigation(self, script, obj):
"""Returns True if obj should be excluded from simple navigation."""
if self._include_in_simple_navigation(obj):
tokens = ["OBJECT NAVIGATOR: Not excluding", obj, ": explicit inclusion"]
debug.printTokens(debug.LEVEL_INFO, tokens, True)
return False
# isLayoutOnly should catch things that really should be skipped.
#
# You do not want to exclude all sections because they may be focusable, e.g.
# <div tabindex=0>foo</div> should not be excluded, despite the poor authoring.
#
# You do not want to exclude table cells and headers because it will make the
# selectable items in tables non-navigable (e.g. the mail folders in Evolution)
if script.utilities.isLayoutOnly(obj):
tokens = ["OBJECT NAVIGATOR: Excluding", obj, ": is layout only"]
debug.printTokens(debug.LEVEL_INFO, tokens, True)
return True
tokens = ["OBJECT NAVIGATOR: Not excluding", obj]
debug.printTokens(debug.LEVEL_INFO, tokens, True)
return False
def _children(self, script, obj):
"""Returns a list of children for obj, taking simple navigation into account."""
if not AXObject.get_child_count(obj):
return []
children = list(AXObject.iter_children(obj))
if not self._simplify:
return children
# Add the children of excluded objects to our list of children.
functional_children = []
for child in children:
if self._exclude_from_simple_navigation(script, child):
functional_children.extend(self._children(script, child))
else:
functional_children.append(child)
return functional_children
def _parent(self, script, obj):
"""Returns the parent for obj, taking simple navigation into account."""
parent = AXObject.get_parent(obj)
if not self._simplify:
return parent
# The first non-excluded ancestor is the functional parent.
while parent is not None and self._exclude_from_simple_navigation(script, parent):
parent = AXObject.get_parent(parent)
return parent
def _set_navigator_focus(self, obj):
"""Changes the navigator focus, storing the previous focus."""
self._last_navigator_focus = self._navigator_focus
self._navigator_focus = obj
def update(self):
"""Updates the navigator focus to Orca's object of interest."""
mode, region = focus_manager.getManager().get_active_mode_and_object_of_interest()
obj = region or focus_manager.getManager().get_locus_of_focus()
if self._last_locus_of_focus == obj \
or (region is None and mode == focus_manager.FLAT_REVIEW):
return
self._navigator_focus = obj
self._last_locus_of_focus = obj
def present(self, script):
"""Presents the current navigator focus to the user."""
tokens = ["OBJECT NAVIGATOR: Presenting", self._navigator_focus]
debug.printTokens(debug.LEVEL_INFO, tokens, True)
focus_manager.getManager().emit_region_changed(
self._navigator_focus, mode=focus_manager.OBJECT_NAVIGATOR)
script.presentObject(self._navigator_focus, priorObj=self._last_navigator_focus)
def up(self, script, event=None):
"""Moves the navigator focus to the parent of the current focus."""
self.update()
parent = self._parent(script, self._navigator_focus)
if parent is not None:
self._set_navigator_focus(parent)
self.present(script)
else:
script.presentMessage(messages.NAVIGATOR_NO_PARENT)
def down(self, script, event=None):
"""Moves the navigator focus to the first child of the current focus."""
self.update()
children = self._children(script, self._navigator_focus)
if not children:
script.presentMessage(messages.NAVIGATOR_NO_CHILDREN)
return
self._set_navigator_focus(children[0])
self.present(script)
def next(self, script, event=None):
"""Moves the navigator focus to the next sibling of the current focus."""
self.update()
parent = self._parent(script, self._navigator_focus)
if parent is None:
script.presentMessage(messages.NAVIGATOR_NO_NEXT)
return
siblings = self._children(script, parent)
if self._navigator_focus in siblings:
index = siblings.index(self._navigator_focus)
if index < len(siblings) - 1:
self._set_navigator_focus(siblings[index+1])
self.present(script)
else:
script.presentMessage(messages.NAVIGATOR_NO_NEXT)
else:
self._set_navigator_focus(parent)
self.present(script)
def previous(self, script, event=None):
"""Moves the navigator focus to the previous sibling of the current focus."""
self.update()
parent = self._parent(script, self._navigator_focus)
if parent is None:
script.presentMessage(messages.NAVIGATOR_NO_PREVIOUS)
return
siblings = self._children(script, parent)
if self._navigator_focus in siblings:
index = siblings.index(self._navigator_focus)
if index > 0:
self._set_navigator_focus(siblings[index-1])
self.present(script)
else:
script.presentMessage(messages.NAVIGATOR_NO_PREVIOUS)
else:
self._set_navigator_focus(parent)
self.present(script)
def toggle_simplify(self, script, event=None):
"""Toggles simplified navigation."""
self._simplify = not self._simplify
if self._simplify:
script.presentMessage(messages.NAVIGATOR_SIMPLIFIED_ENABLED)
else:
script.presentMessage(messages.NAVIGATOR_SIMPLIFIED_DISABLED)
return True
def perform_action(self, script, event=None):
"""Attempts to click on the current focus."""
if AXEventSynthesizer.try_all_clickable_actions(self._navigator_focus):
return True
AXEventSynthesizer.click_object(self._navigator_focus, 1)
return True
_navigator = ObjectNavigator()
def getNavigator():
"""Returns the Object Navigator"""
return _navigator
Mini Shell