| from __future__ import annotations |
|
|
| from fractions import Fraction |
| from typing import cast |
|
|
| from textual.geometry import Size, Region |
| from textual._layout import ArrangeResult, Layout, WidgetPlacement |
|
|
| from textual.widget import Widget |
|
|
|
|
| class HorizontalLayout(Layout): |
| """Used to layout Widgets horizontally on screen, from left to right. Since Widgets naturally |
| fill the space of their parent container, all widgets used in a horizontal layout should have a specified. |
| """ |
|
|
| name = "horizontal" |
|
|
| def arrange( |
| self, parent: Widget, children: list[Widget], size: Size |
| ) -> ArrangeResult: |
|
|
| placements: list[WidgetPlacement] = [] |
| add_placement = placements.append |
|
|
| x = max_height = Fraction(0) |
| parent_size = parent.outer_size |
|
|
| styles = [child.styles for child in children if child.styles.width is not None] |
| total_fraction = sum( |
| [int(style.width.value) for style in styles if style.width.is_fraction] |
| ) |
| fraction_unit = Fraction(size.width, total_fraction or 1) |
|
|
| box_models = [ |
| widget._get_box_model(size, parent_size, fraction_unit) |
| for widget in cast("list[Widget]", children) |
| ] |
|
|
| margins = [ |
| max((box1.margin.right, box2.margin.left)) |
| for box1, box2 in zip(box_models, box_models[1:]) |
| ] |
| if box_models: |
| margins.append(box_models[-1].margin.right) |
|
|
| x = Fraction(box_models[0].margin.left if box_models else 0) |
|
|
| displayed_children = [child for child in children if child.display] |
|
|
| _Region = Region |
| _WidgetPlacement = WidgetPlacement |
| for widget, box_model, margin in zip(children, box_models, margins): |
| content_width, content_height, box_margin = box_model |
| offset_y = box_margin.top |
| next_x = x + content_width |
| region = _Region( |
| int(x), offset_y, int(next_x - int(x)), int(content_height) |
| ) |
| max_height = max( |
| max_height, content_height + offset_y + box_model.margin.bottom |
| ) |
| add_placement(_WidgetPlacement(region, box_model.margin, widget, 0)) |
| x = next_x + margin |
|
|
| return placements, set(displayed_children) |
|
|
