Struct SidePanel 

pub struct SidePanel<'a, Msg> { /* private fields */ }

A panel docked to the left or right of a body, on its own surface.

The application owns whether the panel is open, how wide it is and which view it shows. The plain panel is just a surface next to the body; capabilities are opt-in:

• SidePanel::on_toggle makes the edge between panel and body interactive. The edge is a tone difference, never a line: on hover it brightens one step and a two-cell toggle appears at its middle, a ‹ or › on a raised surface reaching one cell into the body. Pointing at the toggle raises it a step more and shows the pillar ▌ in its first cell, pressing it raises it one more; clicking toggles. Tab reaches the edge and shows the same toggle, where Enter or Space toggles, and the global action toggle-panel (alt+b by default) toggles from anywhere inside the panel or the body. Opening and closing slide over twice motion.enter. Dragging a closed edge half the minimum width into the body opens the panel.
• SidePanel::on_resize lets the edge be dragged, and moved with ←/→ while focused, within SidePanel::limits.
• SidePanel::strip adds an activity bar: a column of view icons at the outer edge, beside the open panel and left behind when it collapses. SidePanel::active_view marks the shown view’s icon, raised with the pillar. Clicking another icon switches to its view (opening the panel if it is closed); clicking the shown view’s icon closes the panel. Tab reaches the strip, where ↑/↓ move and Enter or Space act like a click.
• SidePanel::closed chooses what closing leaves: the strip (Closed::Collapse, the default) or only an invisible edge column (Closed::Hide).

Style keys: side-panel (bg), side-strip (bg), side-strip-item (fg, bg, pillar) with hover, selected, focus and pressed, split-handle for the edge and side-toggle (bg, fg, pillar) with hover, focus and pressed for the toggle. Icons: edge-left, edge-right.

Implementations

impl<'a, Msg: 'static> SidePanel<'a, Msg>

pub fn new(width: u16) -> Self

An open panel width columns wide, docked left.

pub fn side(self, side: Side) -> Self

Docks the panel to side.

pub fn open(self, open: bool) -> Self

Whether the panel is open; true by default.

pub fn closed(self, closed: Closed) -> Self

What closing leaves behind: Closed::Collapse (the default) keeps the icon strip, Closed::Hide hides the strip too and leaves only the edge column.

pub fn on_toggle(self, message: impl Fn(bool) -> Msg + 'static) -> Self

Makes the edge toggle the panel; the message carries the new open state.

pub fn on_resize(self, message: impl Fn(u16) -> Msg + 'static) -> Self

Makes the edge resize the panel; the message carries the new width within the limits.

pub fn limits(self, min: u16, max: impl Into<Option<u16>>) -> Self

The narrowest and widest the panel can be, in columns: limits(18, 48) for a range, or limits(18, None) for no upper limit. By default 8 and no upper limit; whatever the limits, the body keeps at least a quarter of the area. A max below min counts as min.

pub fn strip( self, icons: impl IntoIterator<Item = impl Into<String>>, message: impl Fn(u16) -> Msg + 'static, ) -> Self

Adds an activity bar of these view icons at the outer edge. Clicking an icon sends its index, meaning “show this view”: set the view and open the panel in update. The icon of the active_view instead closes the open panel through on_toggle.

pub fn active_view(self, index: u16) -> Self

The index of the strip icon whose view the panel shows; it is raised with the pillar while the panel is open.

pub fn panel(self, build: impl FnOnce(&mut View<'_, Msg>) + 'a) -> Self

The panel’s content.

pub fn body(self, build: impl FnOnce(&mut View<'_, Msg>) + 'a) -> Self

The body beside the panel.

pub fn show<'v>(self, ui: &'v mut View<'_, Msg>) -> NodeMut<'v, Msg>

Adds the panel and its body to ui, filling the space they get.