setRatio method
Set the split ratio directly (clamped between 0.0 and 1.0).
Implementation
void setRatio(double ratio) {
_ratio = ratio.clamp(0.0, 1.0);
_leadingExtent = null;
_isLeadingCollapsed = _ratio == 0.0;
_isTrailingCollapsed = _ratio == 1.0;
notifyListeners();
}