hideHandles method Null safety
Destroys the handles by removing them from overlay.
Implementation
void hideHandles() {
  if (_handles != null) {
    _handles![0].remove();
    _handles![1].remove();
    _handles = null;
  }
}Destroys the handles by removing them from overlay.
void hideHandles() {
  if (_handles != null) {
    _handles![0].remove();
    _handles![1].remove();
    _handles = null;
  }
}