setDetachedFromWindowHandle method
Implementation
void setDetachedFromWindowHandle(bool flag) {
  if (!handleGestureBySelf()) {
    _dispatcher.listenDetachedFromWindow = flag;
  }
}
void setDetachedFromWindowHandle(bool flag) {
  if (!handleGestureBySelf()) {
    _dispatcher.listenDetachedFromWindow = flag;
  }
}