418 lines
14 KiB
Python
418 lines
14 KiB
Python
"""
|
|
Wrapper for the layout.
|
|
"""
|
|
from typing import Dict, Generator, Iterable, List, Optional, Union
|
|
|
|
from prompt_toolkit.buffer import Buffer
|
|
|
|
from .containers import (
|
|
AnyContainer,
|
|
ConditionalContainer,
|
|
Container,
|
|
Window,
|
|
to_container,
|
|
)
|
|
from .controls import BufferControl, SearchBufferControl, UIControl
|
|
|
|
__all__ = [
|
|
"Layout",
|
|
"InvalidLayoutError",
|
|
"walk",
|
|
]
|
|
|
|
FocusableElement = Union[str, Buffer, UIControl, AnyContainer]
|
|
|
|
|
|
class Layout:
|
|
"""
|
|
The layout for a prompt_toolkit
|
|
:class:`~prompt_toolkit.application.Application`.
|
|
This also keeps track of which user control is focused.
|
|
|
|
:param container: The "root" container for the layout.
|
|
:param focused_element: element to be focused initially. (Can be anything
|
|
the `focus` function accepts.)
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
container: AnyContainer,
|
|
focused_element: Optional[FocusableElement] = None,
|
|
):
|
|
|
|
self.container = to_container(container)
|
|
self._stack: List[Window] = []
|
|
|
|
# Map search BufferControl back to the original BufferControl.
|
|
# This is used to keep track of when exactly we are searching, and for
|
|
# applying the search.
|
|
# When a link exists in this dictionary, that means the search is
|
|
# currently active.
|
|
# Map: search_buffer_control -> original buffer control.
|
|
self.search_links: Dict[SearchBufferControl, BufferControl] = {}
|
|
|
|
# Mapping that maps the children in the layout to their parent.
|
|
# This relationship is calculated dynamically, each time when the UI
|
|
# is rendered. (UI elements have only references to their children.)
|
|
self._child_to_parent: Dict[Container, Container] = {}
|
|
|
|
if focused_element is None:
|
|
try:
|
|
self._stack.append(next(self.find_all_windows()))
|
|
except StopIteration:
|
|
raise InvalidLayoutError(
|
|
"Invalid layout. The layout does not contain any Window object."
|
|
)
|
|
else:
|
|
self.focus(focused_element)
|
|
|
|
# List of visible windows.
|
|
self.visible_windows: List[Window] = [] # List of `Window` objects.
|
|
|
|
def __repr__(self) -> str:
|
|
return "Layout(%r, current_window=%r)" % (self.container, self.current_window)
|
|
|
|
def find_all_windows(self) -> Generator[Window, None, None]:
|
|
"""
|
|
Find all the :class:`.UIControl` objects in this layout.
|
|
"""
|
|
for item in self.walk():
|
|
if isinstance(item, Window):
|
|
yield item
|
|
|
|
def find_all_controls(self) -> Iterable[UIControl]:
|
|
for container in self.find_all_windows():
|
|
yield container.content
|
|
|
|
def focus(self, value: FocusableElement) -> None:
|
|
"""
|
|
Focus the given UI element.
|
|
|
|
`value` can be either:
|
|
|
|
- a :class:`.UIControl`
|
|
- a :class:`.Buffer` instance or the name of a :class:`.Buffer`
|
|
- a :class:`.Window`
|
|
- Any container object. In this case we will focus the :class:`.Window`
|
|
from this container that was focused most recent, or the very first
|
|
focusable :class:`.Window` of the container.
|
|
"""
|
|
# BufferControl by buffer name.
|
|
if isinstance(value, str):
|
|
for control in self.find_all_controls():
|
|
if isinstance(control, BufferControl) and control.buffer.name == value:
|
|
self.focus(control)
|
|
return
|
|
raise ValueError(
|
|
"Couldn't find Buffer in the current layout: %r." % (value,)
|
|
)
|
|
|
|
# BufferControl by buffer object.
|
|
elif isinstance(value, Buffer):
|
|
for control in self.find_all_controls():
|
|
if isinstance(control, BufferControl) and control.buffer == value:
|
|
self.focus(control)
|
|
return
|
|
raise ValueError(
|
|
"Couldn't find Buffer in the current layout: %r." % (value,)
|
|
)
|
|
|
|
# Focus UIControl.
|
|
elif isinstance(value, UIControl):
|
|
if value not in self.find_all_controls():
|
|
raise ValueError(
|
|
"Invalid value. Container does not appear in the layout."
|
|
)
|
|
if not value.is_focusable():
|
|
raise ValueError("Invalid value. UIControl is not focusable.")
|
|
|
|
self.current_control = value
|
|
|
|
# Otherwise, expecting any Container object.
|
|
else:
|
|
value = to_container(value)
|
|
|
|
if isinstance(value, Window):
|
|
# This is a `Window`: focus that.
|
|
if value not in self.find_all_windows():
|
|
raise ValueError(
|
|
"Invalid value. Window does not appear in the layout: %r"
|
|
% (value,)
|
|
)
|
|
|
|
self.current_window = value
|
|
else:
|
|
# Focus a window in this container.
|
|
# If we have many windows as part of this container, and some
|
|
# of them have been focused before, take the last focused
|
|
# item. (This is very useful when the UI is composed of more
|
|
# complex sub components.)
|
|
windows = []
|
|
for c in walk(value, skip_hidden=True):
|
|
if isinstance(c, Window) and c.content.is_focusable():
|
|
windows.append(c)
|
|
|
|
# Take the first one that was focused before.
|
|
for w in reversed(self._stack):
|
|
if w in windows:
|
|
self.current_window = w
|
|
return
|
|
|
|
# None was focused before: take the very first focusable window.
|
|
if windows:
|
|
self.current_window = windows[0]
|
|
return
|
|
|
|
raise ValueError(
|
|
"Invalid value. Container cannot be focused: %r" % (value,)
|
|
)
|
|
|
|
def has_focus(self, value: FocusableElement) -> bool:
|
|
"""
|
|
Check whether the given control has the focus.
|
|
:param value: :class:`.UIControl` or :class:`.Window` instance.
|
|
"""
|
|
if isinstance(value, str):
|
|
if self.current_buffer is None:
|
|
return False
|
|
return self.current_buffer.name == value
|
|
if isinstance(value, Buffer):
|
|
return self.current_buffer == value
|
|
if isinstance(value, UIControl):
|
|
return self.current_control == value
|
|
else:
|
|
value = to_container(value)
|
|
if isinstance(value, Window):
|
|
return self.current_window == value
|
|
else:
|
|
# Check whether this "container" is focused. This is true if
|
|
# one of the elements inside is focused.
|
|
for element in walk(value):
|
|
if element == self.current_window:
|
|
return True
|
|
return False
|
|
|
|
@property
|
|
def current_control(self) -> UIControl:
|
|
"""
|
|
Get the :class:`.UIControl` to currently has the focus.
|
|
"""
|
|
return self._stack[-1].content
|
|
|
|
@current_control.setter
|
|
def current_control(self, control: UIControl) -> None:
|
|
"""
|
|
Set the :class:`.UIControl` to receive the focus.
|
|
"""
|
|
for window in self.find_all_windows():
|
|
if window.content == control:
|
|
self.current_window = window
|
|
return
|
|
|
|
raise ValueError("Control not found in the user interface.")
|
|
|
|
@property
|
|
def current_window(self) -> Window:
|
|
" Return the :class:`.Window` object that is currently focused. "
|
|
return self._stack[-1]
|
|
|
|
@current_window.setter
|
|
def current_window(self, value: Window):
|
|
" Set the :class:`.Window` object to be currently focused. "
|
|
self._stack.append(value)
|
|
|
|
@property
|
|
def is_searching(self) -> bool:
|
|
" True if we are searching right now. "
|
|
return self.current_control in self.search_links
|
|
|
|
@property
|
|
def search_target_buffer_control(self) -> Optional[BufferControl]:
|
|
"""
|
|
Return the :class:`.BufferControl` in which we are searching or `None`.
|
|
"""
|
|
# Not every `UIControl` is a `BufferControl`. This only applies to
|
|
# `BufferControl`.
|
|
control = self.current_control
|
|
|
|
if isinstance(control, SearchBufferControl):
|
|
return self.search_links.get(control)
|
|
else:
|
|
return None
|
|
|
|
def get_focusable_windows(self) -> Iterable[Window]:
|
|
"""
|
|
Return all the :class:`.Window` objects which are focusable (in the
|
|
'modal' area).
|
|
"""
|
|
for w in self.walk_through_modal_area():
|
|
if isinstance(w, Window) and w.content.is_focusable():
|
|
yield w
|
|
|
|
def get_visible_focusable_windows(self) -> List[Window]:
|
|
"""
|
|
Return a list of :class:`.Window` objects that are focusable.
|
|
"""
|
|
# focusable windows are windows that are visible, but also part of the
|
|
# modal container. Make sure to keep the ordering.
|
|
visible_windows = self.visible_windows
|
|
return [w for w in self.get_focusable_windows() if w in visible_windows]
|
|
|
|
@property
|
|
def current_buffer(self) -> Optional[Buffer]:
|
|
"""
|
|
The currently focused :class:`~.Buffer` or `None`.
|
|
"""
|
|
ui_control = self.current_control
|
|
if isinstance(ui_control, BufferControl):
|
|
return ui_control.buffer
|
|
return None
|
|
|
|
def get_buffer_by_name(self, buffer_name: str) -> Optional[Buffer]:
|
|
"""
|
|
Look in the layout for a buffer with the given name.
|
|
Return `None` when nothing was found.
|
|
"""
|
|
for w in self.walk():
|
|
if isinstance(w, Window) and isinstance(w.content, BufferControl):
|
|
if w.content.buffer.name == buffer_name:
|
|
return w.content.buffer
|
|
return None
|
|
|
|
@property
|
|
def buffer_has_focus(self) -> bool:
|
|
"""
|
|
Return `True` if the currently focused control is a
|
|
:class:`.BufferControl`. (For instance, used to determine whether the
|
|
default key bindings should be active or not.)
|
|
"""
|
|
ui_control = self.current_control
|
|
return isinstance(ui_control, BufferControl)
|
|
|
|
@property
|
|
def previous_control(self) -> UIControl:
|
|
"""
|
|
Get the :class:`.UIControl` to previously had the focus.
|
|
"""
|
|
try:
|
|
return self._stack[-2].content
|
|
except IndexError:
|
|
return self._stack[-1].content
|
|
|
|
def focus_last(self) -> None:
|
|
"""
|
|
Give the focus to the last focused control.
|
|
"""
|
|
if len(self._stack) > 1:
|
|
self._stack = self._stack[:-1]
|
|
|
|
def focus_next(self) -> None:
|
|
"""
|
|
Focus the next visible/focusable Window.
|
|
"""
|
|
windows = self.get_visible_focusable_windows()
|
|
|
|
if len(windows) > 0:
|
|
try:
|
|
index = windows.index(self.current_window)
|
|
except ValueError:
|
|
index = 0
|
|
else:
|
|
index = (index + 1) % len(windows)
|
|
|
|
self.focus(windows[index])
|
|
|
|
def focus_previous(self) -> None:
|
|
"""
|
|
Focus the previous visible/focusable Window.
|
|
"""
|
|
windows = self.get_visible_focusable_windows()
|
|
|
|
if len(windows) > 0:
|
|
try:
|
|
index = windows.index(self.current_window)
|
|
except ValueError:
|
|
index = 0
|
|
else:
|
|
index = (index - 1) % len(windows)
|
|
|
|
self.focus(windows[index])
|
|
|
|
def walk(self) -> Iterable[Container]:
|
|
"""
|
|
Walk through all the layout nodes (and their children) and yield them.
|
|
"""
|
|
for i in walk(self.container):
|
|
yield i
|
|
|
|
def walk_through_modal_area(self) -> Iterable[Container]:
|
|
"""
|
|
Walk through all the containers which are in the current 'modal' part
|
|
of the layout.
|
|
"""
|
|
# Go up in the tree, and find the root. (it will be a part of the
|
|
# layout, if the focus is in a modal part.)
|
|
root: Container = self.current_window
|
|
while not root.is_modal() and root in self._child_to_parent:
|
|
root = self._child_to_parent[root]
|
|
|
|
for container in walk(root):
|
|
yield container
|
|
|
|
def update_parents_relations(self) -> None:
|
|
"""
|
|
Update child->parent relationships mapping.
|
|
"""
|
|
parents = {}
|
|
|
|
def walk(e: Container) -> None:
|
|
for c in e.get_children():
|
|
parents[c] = e
|
|
walk(c)
|
|
|
|
walk(self.container)
|
|
|
|
self._child_to_parent = parents
|
|
|
|
def reset(self) -> None:
|
|
# Remove all search links when the UI starts.
|
|
# (Important, for instance when control-c is been pressed while
|
|
# searching. The prompt cancels, but next `run()` call the search
|
|
# links are still there.)
|
|
self.search_links.clear()
|
|
|
|
self.container.reset()
|
|
|
|
def get_parent(self, container: Container) -> Optional[Container]:
|
|
"""
|
|
Return the parent container for the given container, or ``None``, if it
|
|
wasn't found.
|
|
"""
|
|
try:
|
|
return self._child_to_parent[container]
|
|
except KeyError:
|
|
return None
|
|
|
|
|
|
class InvalidLayoutError(Exception):
|
|
pass
|
|
|
|
|
|
def walk(container: Container, skip_hidden: bool = False) -> Iterable[Container]:
|
|
"""
|
|
Walk through layout, starting at this container.
|
|
"""
|
|
# When `skip_hidden` is set, don't go into disabled ConditionalContainer containers.
|
|
if (
|
|
skip_hidden
|
|
and isinstance(container, ConditionalContainer)
|
|
and not container.filter()
|
|
):
|
|
return
|
|
|
|
yield container
|
|
|
|
for c in container.get_children():
|
|
# yield from walk(c)
|
|
yield from walk(c, skip_hidden=skip_hidden)
|