Current File : //snap/core22/current/usr/share/subiquity/subiquitycore/ui/selector.py
# Copyright 2017 Canonical, Ltd.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, version 3.
#
# This program 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
from urwid import (
ACTIVATE,
AttrWrap,
CompositeCanvas,
connect_signal,
LineBox,
Padding as UrwidPadding,
PopUpLauncher,
Text,
)
from subiquitycore.ui.container import (
Columns,
ListBox,
WidgetWrap,
)
from subiquitycore.ui.utils import (
Color,
)
from subiquitycore.ui.width import widget_width
class ClickableThing(WidgetWrap):
signals = ['click']
def selectable(self):
return True
def render(self, size, focus=False):
c = super().render(size, focus)
if focus:
# create a new canvas so we can add a cursor
c = CompositeCanvas(c)
c.cursor = self.get_cursor_coords(size)
return c
def get_cursor_coords(self, size):
"""
Return the position of the cursor if visible. This method
is required for widgets that display a cursor.
"""
return 0, 0
def move_cursor_to_coords(self, size, x, y):
return True
def keypress(self, size, key):
if self._command_map[key] != ACTIVATE:
return key
self._emit('click')
class _PopUpSelectDialog(WidgetWrap):
"""A list of PopUpButtons with a box around them."""
def __init__(self, parent, cur_index):
self.parent = parent
group = []
for i, option in enumerate(self.parent._options):
if option.enabled:
btn = ClickableThing(option.label)
connect_signal(btn, 'click', self.click, i)
if i == cur_index:
rhs = '\N{BLACK LEFT-POINTING SMALL TRIANGLE} '
else:
rhs = ''
else:
btn = option.label
rhs = ''
row = Columns([
(1, Text("")),
btn,
(2, Text(rhs)),
])
if option.enabled:
row = AttrWrap(row, 'menu_button', 'menu_button focus')
else:
row = AttrWrap(row, 'info_minor')
btn = UrwidPadding(row, width=self.parent._padding.width)
group.append(btn)
list_box = ListBox(group)
list_box.base_widget.focus_position = cur_index
super().__init__(Color.body(LineBox(list_box)))
def click(self, btn, index):
self.parent.index = index
self.parent.close_pop_up()
def keypress(self, size, key):
if key == 'esc':
self.parent.close_pop_up()
else:
return super().keypress(size, key)
class SelectorError(Exception):
pass
class Option:
def __init__(self, val):
if not isinstance(val, tuple):
if isinstance(val, Option):
self.label = val.label
self.enabled = val.enabled
self.value = val.value
elif isinstance(val, str):
self.label = val
self.enabled = True
self.value = val
else:
raise SelectorError(f"invalid option {val!r}")
elif len(val) == 1:
self.label = val[0]
self.enabled = True
self.value = val[0]
elif len(val) == 2:
self.label = val[0]
self.enabled = val[1]
self.value = val[0]
elif len(val) == 3:
self.label = val[0]
self.enabled = val[1]
self.value = val[2]
else:
raise SelectorError("invalid option %r", val)
if isinstance(self.label, str):
self.label = Text(_(self.label))
class _Launcher(PopUpLauncher):
# PopUpLauncher is a WidgetDecoration, which means base_widget
# steps past it. This means that if Selector just inherited from
# PopUpLauncher, calling .base_widget on a (say) Padding
# containing a Selector would return the SelectableIcon, not the
# Selector. This is unhelpful, to put it mildly, so we do some
# proxying about so that PopUpLauncher can inherit from WidgetWrap
# instead.
def __init__(self, parent, child):
self.parent = parent
super().__init__(child)
def create_pop_up(self):
return self.parent.create_pop_up()
def get_pop_up_parameters(self):
return self.parent.get_pop_up_parameters()
class Selector(WidgetWrap):
"""A widget that allows the user to chose between options by popping
up a list of options.
(A bit like <select> in an HTML form).
"""
signals = ['select']
def __init__(self, opts, index=0):
self._icon = ClickableThing(Text(""))
self._padding = UrwidPadding(AttrWrap(
Columns([
(1, Text('[')),
self._icon,
(3, Text('\N{BLACK DOWN-POINTING SMALL TRIANGLE} ]')),
], dividechars=1),
'menu_button', 'menu_button focus'))
options = []
for opt in opts:
options.append(Option(opt))
self.options = options
self._set_index(index)
super().__init__(_Launcher(self, self._padding))
def get_natural_width(self):
return self._padding.width
def keypress(self, size, key):
if self._command_map[key] != ACTIVATE:
return key
self.open_pop_up()
def _set_index(self, val):
self._icon._w = self._options[val].label
self._index = val
@property
def index(self):
return self._index
@index.setter
def index(self, val):
self._emit('select', self._options[val].value)
self._set_index(val)
@property
def options(self):
return self._options[:]
@options.setter
def options(self, val):
self._options = val
self._padding.width = max(
[widget_width(o.label) for o in self._options]) + 6
def option_by_label(self, label):
for opt in self._options:
if opt.label == label:
return opt
def option_by_value(self, value):
for opt in self._options:
if opt.value == value:
return opt
def option_by_index(self, index):
return self._options[index]
@property
def value(self):
return self._options[self._index].value
@value.setter
def value(self, val):
for i, opt in enumerate(self._options):
if opt.value == val:
self._set_index(i)
return
raise AttributeError("cannot set value to %r", val)
def create_pop_up(self):
return _PopUpSelectDialog(self, self.index)
def get_pop_up_parameters(self):
# line on left, space, line on right
return {'left': 0, 'top': -self.index - 1,
'overlay_width': self._padding.width,
'overlay_height': len(self._options) + 2}
def open_pop_up(self):
self._w.open_pop_up()
def close_pop_up(self):
self._w.close_pop_up()
Mini Shell