AbstractProtectedconstructorProtected ReadonlyobserversProtectedisProtectedisTrue while AbstractTrace.getStateAt computes state at a temporarily moved cursor. Enforces (structurally, not just by documentation) that state getters never notify observers.
Protected AbstractdimensionAbstractstateProtected AbstractoutProtected AbstractmovableRuns action with this element's observers muted.
A cursor move normally is the announcement -- moveToIndex notifies, and
everything downstream of it speaks, brailles and highlights. That is wrong
for a move the reader did not make and is not waiting to hear: the
description dialog's layer tabs relocate the reader in the chart while the
modal is open, and the trace's announcement would land in the same live
region the dialog is using, so one of the two is dropped. The caller
announces afterwards, once, when the reader is back on the chart.
Nesting is safe and the flag is restored on every path, including a throw, because a flag left raised would silence the chart for good.
The moves to make in silence
ProtectedgetGets safe row and column indices to prevent accessing undefined values
Object with safe row and column indices
Notifies all registered observers with the current state.
Notifies observers that an out-of-bounds condition occurred.
The rotor's LOWER and HIGHER VALUE search. The base is a no-op that reports the boundary: a trace that can compare overrides it, and supportsCompareMode offers the two modes exactly where it does.
Utility function to compare point values for rotor functionality
boolean value
ProtectedcompareRotor compare search along one row of numeric values.
Steps from the current column in the given direction and moves to the first value that satisfies the comparison; reports the rotor boundary when nothing further qualifies. For the traces whose values are a plain numeric grid indexed [row][col]; a trace with a richer layout (the bar's orientation-normalised rows, the candlestick's segments) keeps its own.
The values of the row being searched
Which way to search
Whether a lower or a higher value is sought
True when a matching value was found and moved to
Whether the rotor offers its lower and higher value modes on this trace.
Exactly when the trace overrides moveToNextCompareValue. The base search is a no-op that reports a boundary, so offering the modes without one told a reader "No lower value found" with a lower value beside them, or said nothing at all; tying the offer to the search keeps the two from drifting apart again. A subclass can still override this to withhold the modes (scatter, whose arrows walk points rather than values), and a trace that compares only through the rotor's arrow methods must override it to offer them.
Returns the display name for the default data navigation mode. Override to provide a trace-specific name (e.g., "ROW AND COLUMN NAVIGATION" for scatter).
Returns the rotor's compare-mode labels and boundary-message nouns. Override to rename the two compare units for a trace-specific semantic (e.g., the candlestick delta layer uses "above line" / "below line").
Moves the active point to the (x, y) pointer location and returns directional guidance toward the nearest data geometry.
Combines navigation and guidance into a single call so traces compute
findNearestPoint only once per pointer event. Default returns null
for non-trace contexts.
Screen-space x position of the pointer/finger
Screen-space y position of the pointer/finger
Guidance state, or null when unavailable
Interface for plot traces that support keyboard navigation and movement.