selectedRect method
Implementation
Rect? selectedRect(int first, int last) {
if (count <= 0 || last <= start || first >= start + count) return null;
var a = (first - start).clamp(0, count) / count;
var b = (last - start).clamp(0, count) / count;
if (rtl) {
a = 1 - a;
b = 1 - b;
}
return Rect.fromLTRB(
bounds.left + bounds.width * math.min(a, b),
bounds.top,
bounds.left + bounds.width * math.max(a, b),
bounds.bottom,
);
}