Draw a panel

Panel, from retroglyph-ui, is a bordered, optionally titled, filled rectangle: the box every other widget in this crate typically sits inside. It’s a plain Widget like the rest of the crate: build it, then render it into a Surface-shaped area, no Backend type parameter involved.

Rendering into a sub-area

Surface::scope narrows a surface to one rectangle so a widget draws relative to that rectangle’s own (0, 0) instead of the whole screen’s. 11_sokoban’s status pane is exactly this: a Panel with a title, filled and bordered into the right-hand column reserved for it:

        Panel::new()
            .title("Status")
            .render(&mut surface.scope(status_area));

status_area is one of the Rects a split_h call produced earlier in the same function; see Split a layout for where that comes from. Content drawn after the Panel call (the move counter, the key legend) is offset from status_area’s own top-left, one cell in from the border it just drew, matching the interior inset Panel reserves for its box outline.

Styling and theming

Panel::border_style/fill_style set the outline and background directly; .title() (and .add_title() for more than one, or a title on the bottom edge) adds a label into the top border. For an app with more than one widget, prefer .theme() over hand-picking border_style/fill_style so every widget’s panel matches the same palette; see Theme a widget.

See also

• Split a layout, for the Rect a Panel renders into.
• Handle a click, for widgets that read pointer/keyboard input instead of only drawing.
• examples/examples/11_sokoban.rs, examples/examples/09_widgets_dashboard.rs, and examples/examples/17_theme_switch.rs for complete panels in context.