Autoclose dialog in Flutter

I want to autoclose dialog a few seconds after opening. The solution that I found is to call Navigator.of(context).pop(); delayed and it works. But the problem occurs if I closed it manually (by clicking outside) before the execution of the Navigator.pop command. Then Navigator.pop just closes the app and I see just a black screen. I need a way to destroy this delay on closing the dialog or to find another workaround.

showDialog(
  context: context,
  builder: (BuildContext builderContext) {
    Future.delayed(Duration(seconds: 5), () {
      Navigator.of(context).pop();
    });

    return AlertDialog(
      backgroundColor: Colors.red,
      title: Text('Title'),
      content: SingleChildScrollView(
        child: Text('Content'),
      ),
    );
  }
);

You can use a Timer to achieve this. You can cancel the timer whenever you want.

Declare a timer property in your class:

Timer _timer;

And change your showDialog code like:

showDialog(
  context: context,
  builder: (BuildContext builderContext) {
    _timer = Timer(Duration(seconds: 5), () {
      Navigator.of(context).pop();
    });

    return AlertDialog(
      backgroundColor: Colors.red,
      title: Text('Title'),
      content: SingleChildScrollView(
        child: Text('Content'),
      ),
   );
  }
).then((val){
  if (_timer.isActive) {
    _timer.cancel();
  }
});