# Copyright (C) 2013 Patrick Totzke <patricktotzke@gmail.com>
# This file is released under the GNU GPL, version 3 or a later revision.
import urwid
from .tree import Tree, SimpleTree
[docs]class NoSpaceError(Exception):
"""too little space for requested decoration"""
[docs]class DecoratedTree(Tree):
"""
:class:`Tree` that wraps around another :class:`Tree` and allows to read
original content as well as decorated versions thereof.
"""
def __init__(self, content):
if not isinstance(content, Tree):
# do we need this?
content = SimpleTree(content)
self._tree = content
self.root = self._tree.root
[docs] def get_decorated(self, pos):
"""
return widget that consists of the content of original tree at given
position plus its decoration.
"""
return self.decorate(pos, self[pos])
[docs] def decorate(self, pos, widget, is_first=True):
"""
decorate `widget` according to a position `pos` in the original tree.
setting `is_first` to False indicates that we are decorating a line
that is *part* of the (multi-line) content at this position, but not
the first part. This allows to omit incoming arrow heads for example.
"""
return widget
# pass on everything else to the original tree.
[docs] def parent_position(self, pos):
return self._tree.parent_position(pos)
[docs] def first_child_position(self, pos):
return self._tree.first_child_position(pos)
[docs] def last_child_position(self, pos):
return self._tree.last_child_position(pos)
[docs] def next_sibling_position(self, pos):
return self._tree.next_sibling_position(pos)
[docs] def prev_sibling_position(self, pos):
return self._tree.prev_sibling_position(pos)
def __getitem__(self, pos):
return self._tree[pos]
[docs]class CollapseMixin(object):
"""
Mixin for :class:`Tree` that allows to collapse subtrees.
This works by overwriting
:meth:`[first|last]_child_position <first_child_position>`, forcing them to
return `None` if the given position is considered collapsed. We use a
(given) callable `is_collapsed` that accepts positions and returns a
boolean to determine which node is considered collapsed.
"""
def __init__(self, is_collapsed=lambda pos: False,
**kwargs):
self._initially_collapsed = is_collapsed
self._divergent_positions = []
[docs] def is_collapsed(self, pos):
"""checks if given position is currently collapsed"""
collapsed = self._initially_collapsed(pos)
if pos in self._divergent_positions:
collapsed = not collapsed
return collapsed
# implement functionality by overwriting local position transformations
# TODO: ATM this assumes we are in a wrapper: it uses self._tree.
# This is not necessarily true, for example for subclasses of SimpleTree!
# maybe define this whole class as a wrapper?
def last_child_position(self, pos):
if self.is_collapsed(pos):
return None
return self._tree.last_child_position(pos)
def first_child_position(self, pos):
if self.is_collapsed(pos):
return None
return self._tree.first_child_position(pos)
def collapsible(self, pos):
return not self._tree.is_leaf(pos)
def set_position_collapsed(self, pos, is_collapsed):
if self.collapsible(pos):
if self._initially_collapsed(pos) == is_collapsed:
if pos in self._divergent_positions:
self._divergent_positions.remove(pos)
else:
if pos not in self._divergent_positions:
self._divergent_positions.append(pos)
def toggle_collapsed(self, pos):
self.set_position_collapsed(pos, not self.is_collapsed(pos))
def collapse(self, pos):
self.set_position_collapsed(pos, True)
def collapse_all(self):
self.set_collapsed_all(True)
def expand_all(self):
self.set_collapsed_all(False)
def set_collapsed_all(self, is_collapsed):
self._initially_collapsed = lambda x: is_collapsed
self._divergent_positions = []
def expand(self, pos):
self.set_position_collapsed(pos, False)
[docs]class CollapseIconMixin(CollapseMixin):
"""
Mixin for :class:`Tree` that allows to collapse subtrees and use
an indicator icon in line decorations.
This Mixin adds the ability to construct collapse-icon for a
position, indicating its collapse status to :class:`CollapseMixin`.
"""
def __init__(self,
is_collapsed=lambda pos: False,
icon_collapsed_char='+',
icon_expanded_char='-',
icon_collapsed_att=None,
icon_expanded_att=None,
icon_frame_left_char='[',
icon_frame_right_char=']',
icon_frame_att=None,
icon_focussed_att=None,
**kwargs):
"""TODO: docstrings"""
CollapseMixin.__init__(self, is_collapsed, **kwargs)
self._icon_collapsed_char = icon_collapsed_char
self._icon_expanded_char = icon_expanded_char
self._icon_collapsed_att = icon_collapsed_att
self._icon_expanded_att = icon_expanded_att
self._icon_frame_left_char = icon_frame_left_char
self._icon_frame_right_char = icon_frame_right_char
self._icon_frame_att = icon_frame_att
self._icon_focussed_att = icon_focussed_att
def _construct_collapse_icon(self, pos):
width = 0
widget = None
char = self._icon_expanded_char
charatt = self._icon_expanded_att
if self.is_collapsed(pos):
char = self._icon_collapsed_char
charatt = self._icon_collapsed_att
if char is not None:
columns = []
if self._icon_frame_left_char is not None:
lchar = self._icon_frame_left_char
charlen = len(lchar)
leftframe = urwid.Text((self._icon_frame_att, lchar))
columns.append((charlen, leftframe))
width += charlen
# next we build out icon widget: we feed all markups to a Text,
# make it selectable (to toggle collapse) if requested
markup = (charatt, char)
widget = urwid.Text(markup)
charlen = len(char)
columns.append((charlen, widget))
width += charlen
if self._icon_frame_right_char is not None:
rchar = self._icon_frame_right_char
charlen = len(rchar)
rightframe = urwid.Text((self._icon_frame_att, rchar))
columns.append((charlen, rightframe))
width += charlen
widget = urwid.Columns(columns)
return width, widget
[docs]class CollapsibleTree(CollapseMixin, DecoratedTree):
"""Undecorated Tree that allows to collapse subtrees"""
def __init__(self, tree, **kwargs):
DecoratedTree.__init__(self, tree)
CollapseMixin.__init__(self, **kwargs)
[docs]class IndentedTree(DecoratedTree):
"""Indent tree nodes according to their depth in the tree"""
def __init__(self, tree, indent=2):
"""
:param tree: tree of widgets to be displayed
:type tree: Tree
:param indent: indentation width
:type indent: int
"""
self._indent = indent
DecoratedTree.__init__(self, tree)
[docs] def decorate(self, pos, widget, is_first=True):
indent = self._tree.depth(pos) * self._indent
cols = [(indent, urwid.SolidFill(' ')), widget]
# construct a Columns, defining all spacer as Box widgets
line = urwid.Columns(cols, box_columns=range(len(cols))[:-1])
return line
[docs]class CollapsibleIndentedTree(CollapseIconMixin, IndentedTree):
"""
Indent collapsible tree nodes according to their depth in the tree and
display icons indicating collapse-status in the gaps.
"""
def __init__(self, walker, icon_offset=1, indent=4, **kwargs):
"""
:param walker: tree of widgets to be displayed
:type walker: Tree
:param indent: indentation width
:type indent: int
:param icon_offset: distance from icon to the eginning of the tree
node.
:type icon_offset: int
"""
self._icon_offset = icon_offset
IndentedTree.__init__(self, walker, indent=indent)
CollapseIconMixin.__init__(self, **kwargs)
[docs] def decorate(self, pos, widget, is_first=True):
"""
builds a list element for given position in the tree.
It consists of the original widget taken from the Tree and some
decoration columns depending on the existence of parent and sibling
positions. The result is a urwid.Columns widget.
"""
void = urwid.SolidFill(' ')
line = None
cols = []
depth = self._tree.depth(pos)
# add spacer filling all but the last indent
if depth > 0:
cols.append((depth * self._indent, void)), # spacer
# construct last indent
# TODO
iwidth, icon = self._construct_collapse_icon(pos)
available_space = self._indent
firstindent_width = self._icon_offset + iwidth
# stop if indent is too small for this decoration
if firstindent_width > available_space:
raise NoSpaceError()
# add icon only for non-leafs
is_leaf = self._tree.is_leaf(pos)
if not is_leaf:
if icon is not None:
# space to the left
cols.append((available_space - firstindent_width,
urwid.SolidFill(' ')))
# icon
icon_pile = urwid.Pile([('pack', icon), void])
cols.append((iwidth, icon_pile))
# spacer until original widget
available_space = self._icon_offset
cols.append((available_space, urwid.SolidFill(' ')))
else: # otherwise just add another spacer
cols.append((self._indent, urwid.SolidFill(' ')))
cols.append(widget) # original widget ]
# construct a Columns, defining all spacer as Box widgets
line = urwid.Columns(cols, box_columns=range(len(cols))[:-1])
return line
[docs]class ArrowTree(IndentedTree):
"""
Decorates the tree by indenting nodes according to their depth and using
the gaps to draw arrows indicate the tree structure.
"""
def __init__(self, walker,
indent=3,
childbar_offset=0,
arrow_hbar_char=u'\u2500',
arrow_hbar_att=None,
arrow_vbar_char=u'\u2502',
arrow_vbar_att=None,
arrow_tip_char=u'\u27a4',
arrow_tip_att=None,
arrow_att=None,
arrow_connector_tchar=u'\u251c',
arrow_connector_lchar=u'\u2514',
arrow_connector_att=None, **kwargs):
"""
:param walker: tree of widgets to be displayed
:type walker: Tree
:param indent: indentation width
:type indent: int
"""
IndentedTree.__init__(self, walker, indent)
self._childbar_offset = childbar_offset
self._arrow_hbar_char = arrow_hbar_char
self._arrow_hbar_att = arrow_hbar_att
self._arrow_vbar_char = arrow_vbar_char
self._arrow_vbar_att = arrow_vbar_att
self._arrow_connector_lchar = arrow_connector_lchar
self._arrow_connector_tchar = arrow_connector_tchar
self._arrow_connector_att = arrow_connector_att
self._arrow_tip_char = arrow_tip_char
self._arrow_tip_att = arrow_tip_att
self._arrow_att = arrow_att
def _construct_spacer(self, pos, acc):
"""
build a spacer that occupies the horizontally indented space between
pos's parent and the root node. It will return a list of tuples to be
fed into a Columns widget.
"""
parent = self._tree.parent_position(pos)
if parent is not None:
grandparent = self._tree.parent_position(parent)
if self._indent > 0 and grandparent is not None:
parent_sib = self._tree.next_sibling_position(parent)
draw_vbar = parent_sib is not None and \
self._arrow_vbar_char is not None
space_width = self._indent - 1 * (draw_vbar) - self._childbar_offset
if space_width > 0:
void = urwid.AttrMap(urwid.SolidFill(' '), self._arrow_att)
acc.insert(0, ((space_width, void)))
if draw_vbar:
barw = urwid.SolidFill(self._arrow_vbar_char)
bar = urwid.AttrMap(barw, self._arrow_vbar_att or
self._arrow_att)
acc.insert(0, ((1, bar)))
return self._construct_spacer(parent, acc)
else:
return acc
def _construct_connector(self, pos):
"""
build widget to be used as "connector" bit between the vertical bar
between siblings and their respective horizontal bars leading to the
arrow tip
"""
# connector symbol, either L or |- shaped.
connectorw = None
connector = None
if self._tree.next_sibling_position(pos) is not None: # |- shaped
if self._arrow_connector_tchar is not None:
connectorw = urwid.Text(self._arrow_connector_tchar)
else: # L shaped
if self._arrow_connector_lchar is not None:
connectorw = urwid.Text(self._arrow_connector_lchar)
if connectorw is not None:
att = self._arrow_connector_att or self._arrow_att
connector = urwid.AttrMap(connectorw, att)
return connector
def _construct_arrow_tip(self, pos):
"""returns arrow tip as (width, widget)"""
arrow_tip = None
width = 0
if self._arrow_tip_char:
txt = urwid.Text(self._arrow_tip_char)
arrow_tip = urwid.AttrMap(
txt, self._arrow_tip_att or self._arrow_att)
width = len(self._arrow_tip_char)
return width, arrow_tip
def _construct_first_indent(self, pos):
"""
build spacer to occupy the first indentation level from pos to the
left. This is separate as it adds arrowtip and sibling connector.
"""
cols = []
void = urwid.AttrMap(urwid.SolidFill(' '), self._arrow_att)
available_width = self._indent
if self._tree.depth(pos) > 0:
connector = self._construct_connector(pos)
if connector is not None:
width = connector.pack()[0]
if width > available_width:
raise NoSpaceError()
available_width -= width
if self._tree.next_sibling_position(pos) is not None:
barw = urwid.SolidFill(self._arrow_vbar_char)
below = urwid.AttrMap(barw, self._arrow_vbar_att or
self._arrow_att)
else:
below = void
# pile up connector and bar
spacer = urwid.Pile([('pack', connector), below])
cols.append((width, spacer))
#arrow tip
awidth, at = self._construct_arrow_tip(pos)
if at is not None:
if awidth > available_width:
raise NoSpaceError()
available_width -= awidth
at_spacer = urwid.Pile([('pack', at), void])
cols.append((awidth, at_spacer))
# bar between connector and arrow tip
if available_width > 0:
barw = urwid.SolidFill(self._arrow_hbar_char)
bar = urwid.AttrMap(
barw, self._arrow_hbar_att or self._arrow_att)
hb_spacer = urwid.Pile([(1, bar), void])
cols.insert(1, (available_width, hb_spacer))
return cols
[docs] def decorate(self, pos, widget, is_first=True):
"""
builds a list element for given position in the tree.
It consists of the original widget taken from the Tree and some
decoration columns depending on the existence of parent and sibling
positions. The result is a urwid.Columns widget.
"""
line = None
if pos is not None:
original_widget = widget
cols = self._construct_spacer(pos, [])
# Construct arrow leading from parent here,
# if we have a parent and indentation is turned on
if self._indent > 0:
if is_first:
indent = self._construct_first_indent(pos)
if indent is not None:
cols = cols + indent
else:
parent = self._tree.parent_position(pos)
if self._indent > 0 and parent is not None:
parent_sib = self._tree.next_sibling_position(pos)
draw_vbar = parent_sib is not None
void = urwid.AttrMap(urwid.SolidFill(' '),
self._arrow_att)
if self._childbar_offset > 0:
cols.append((self._childbar_offset, void))
if draw_vbar:
barw = urwid.SolidFill(self._arrow_vbar_char)
bar = urwid.AttrMap(
barw, self._arrow_vbar_att or self._arrow_att)
rspace_width = self._indent - \
1 - self._childbar_offset
cols.append((1, bar))
cols.append((rspace_width, void))
else:
cols.append((self._indent, void))
# add the original widget for this line
cols.append(original_widget)
# construct a Columns, defining all spacer as Box widgets
line = urwid.Columns(cols, box_columns=range(len(cols))[:-1])
return line
[docs]class CollapsibleArrowTree(CollapseIconMixin, ArrowTree):
"""Arrow-decoration that allows collapsing subtrees"""
def __init__(self, treelistwalker, icon_offset=0, indent=5, **kwargs):
self._icon_offset = icon_offset
ArrowTree.__init__(self, treelistwalker, indent, **kwargs)
CollapseIconMixin.__init__(self, **kwargs)
def _construct_arrow_tip(self, pos):
cols = []
overall_width = self._icon_offset
if self._icon_offset > 0:
# how often we repeat the hbar_char until width icon_offset is
# reached
hbar_char_count = len(self._arrow_hbar_char) / self._icon_offset
barw = urwid.Text(self._arrow_hbar_char * hbar_char_count)
bar = urwid.AttrMap(barw, self._arrow_hbar_att or self._arrow_att)
cols.insert(1, (self._icon_offset, bar))
# add icon only for non-leafs
if self.collapsible(pos):
iwidth, icon = self._construct_collapse_icon(pos)
if icon is not None:
cols.insert(0, (iwidth, icon))
overall_width += iwidth
# get arrow tip
awidth, tip = ArrowTree._construct_arrow_tip(self, pos)
if tip is not None:
cols.append((awidth, tip))
overall_width += awidth
return overall_width, urwid.Columns(cols)