scanner static method

Spinner scanner({ Color? color, int width = 8, ScannerCharSet chars = ScannerChars.blocks, int holdStart = 30, int holdEnd = 9, int trailSteps = 6, Duration fps = const Duration(milliseconds: 40), })

Creates a Knight Rider scanner animation.

The scanner oscillates bidirectionally (left → right → left) with configurable hold frames at each end, producing a glowing sweep effect across the bar.

Parameters:

• color — The bright color for the scanner head (defaults to Colors.purple).
• width — Number of character positions (default 8).
• chars — Character set for active/inactive positions (default ScannerChars.blocks).
• holdStart — Frames to hold at the start position (default 30).
• holdEnd — Frames to hold at the end position (default 9).
• trailSteps — Number of gradient steps in the trail (default 6).
• fps — Frame interval duration (default 40ms, matching opencode).

Implementation

static Spinner scanner({
  Color? color,
  int width = 8,
  ScannerCharSet chars = ScannerChars.blocks,
  int holdStart = 30,
  int holdEnd = 9,
  int trailSteps = 6,
  Duration fps = const Duration(milliseconds: 40),
}) {
  final c = color ?? Colors.purple;
  final trail = deriveTrail(c, steps: trailSteps);
  final inactive = deriveInactive(c);

  final frames = _generateScannerFrames(
    width: width,
    chars: chars,
    trail: trail,
    inactiveColor: inactive,
    holdStart: holdStart,
    holdEnd: holdEnd,
  );

  return Spinner(frames: frames, fps: fps);
}