handleMouseEvent method
Interprets mouse interactions to increment or decrement the selector.
Implementation
void handleMouseEvent(MouseEvent event, int localX, int localY) {
if (event.type != MouseEventType.press) return;
if (localY != 0) return;
final labelLen = label.characters.length;
final displayChars = '$label: < $value >'.characters;
final leftArrowIdx = labelLen + 2;
final rightArrowIdx = displayChars.length - 1;
if (localX == leftArrowIdx) {
decrement();
} else if (localX == rightArrowIdx) {
increment();
}
}