ra8_widget_panel_t Struct Reference

A container widget's child array + stack-layout parameters (#145). More...

#include <ra8_widget.h>

Detailed Description

A container widget's child array + stack-layout parameters (#145).

The flat container ops above (ra8_widget_layout_stack et al.) lay out one array of widgets inside a frame. A panel lifts that into a tree: a panel is itself a ra8_widget_t (bind it with ra8_widget_panel_init), so a panel can be a child of another panel – the dwm-style composition the issue asks for, where the screen is a tree of opt-in pieces. Rendering a panel lays its children out inside the panel's own rect and composites them; routing offers an input event to those children. Everything is caller-owned (the child array and the ra8_box scratch), so a panel allocates nothing (NASA Rule 3) and the same tree runs on the host and on the board.

Invariant

box_scratch holds at least count + 1 nodes.

children covers count entries.

Example:

static ra8_widget_t   kids[2];
static ra8_box_t      scratch[3];
ra8_widget_panel_t    body = {.children = kids, .box_scratch = scratch,
                             .count = 2U, .box_cap = 3U,
                             .axis = k_ra8_widget_axis_row};
ra8_widget_t          panel = {};
(void)ra8_widget_panel_init(&panel, &body);

See also

ra8_widget_panel_init Bind a widget to a panel.

ra8_widget_panel_compose Run the top-level compose cycle.

Since

0.1.0

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The documentation for this struct was generated from the following file:

• libs/ra8_widget/inc/ra8_widget.h