Struct EncoderDevice 

pub struct EncoderDevice {
    pub focus_group: FocusGroup,
}

LPAR-04 §8 Encoder input device adapter.

Holds a FocusGroup and routes encoder events according to the group’s navigate / editing mode:

• Navigate mode (policy.editing == false): positive diff calls focus_next once per detent; negative diff calls focus_prev once per detent. A diff of ±N steps focus N times in the corresponding direction (one step per detent — the simplest correct rule for a discrete encoder).

• Editing mode (policy.editing == true): delivers ObjectEvent::Rotary { diff } to the focused object for any non-zero diff, and ObjectEvent::Key(Key::Enter) for encoder presses.

Mode toggle

An encoder press in either mode inverts policy.editing (LVGL encoder convention: Enter toggles between navigate and edit). The press is delivered as ObjectEvent::Key(Key::Enter) to the focused object before the toggle in editing mode.

Focus group ownership

Each EncoderDevice owns its own FocusGroup, keeping the per-device state isolated (LPAR-04 §8.4).

Fields

focus_group: FocusGroup

Focus traversal and editing policy.

Implementations

impl EncoderDevice

pub fn new() -> Self

Create an encoder device with default focus policy (wrap enabled, navigate mode).

pub fn rotate(&mut self, root: &mut ObjectNode, diff: i32) -> Disposition

Process a rotation event.

• Navigate mode: steps focus diff.abs() times in the direction of the sign (positive → next, negative → prev).
• Editing mode: delivers ObjectEvent::Rotary { diff } to the focused object. Returns Disposition::NoTarget when diff == 0.

pub fn press(&mut self, root: &mut ObjectNode) -> Disposition

Process an encoder press (the physical click of the encoder shaft).

Toggles editing mode and:

• Before toggle from editing → navigate: delivers ObjectEvent::Key(Key::Enter) to the focused object.
• Toggle from navigate → editing: delivers ObjectEvent::Key(Key::Enter) to the focused object after entering editing mode (so the widget sees Enter while in edit mode).

Returns the Disposition of the key delivery, or Disposition::NoTarget if no focused object exists.

pub fn is_editing(&self) -> bool

Return whether the encoder is currently in editing mode.

pub fn set_editing(&mut self, root: &mut ObjectNode, editing: bool)

Directly set editing mode without delivering a key event.

Sets or clears rlvgl_core::object::ObjectStates::EDITED on the currently focused node in root.

Trait Implementations

impl Default for EncoderDevice

fn default() -> Self

Returns the “default value” for a type.