Flutter showDialog with loading spinner and confirmation - flutter

Question

In flutter, I have a showDialog() with cancel and confirm button. The confirm button will trigger a call to an API. What I need is to show a "loading..." in the showDialog window after the click and once the API call is finished to show a success or failure. How can I manage this? Or should I close the window, waiting for the reply and popup a new dialog window with success or false? Thx for any help or better suggestion. Here what I have so far:
void _showAlert(String textLabel, String action, String linkId) {
showDialog(
context: context,
//barrierDismissible: false, // on external click
builder: (_) => new AlertDialog(
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10.0)),
title: new Text(
'Please confirm:',
style: TextStyle(color: Colors.deepOrange, fontWeight: FontWeight.bold),
textAlign: TextAlign.center,
),
content: new Text(
textLabel,
style: new TextStyle(fontSize: 20.0),
),
actions: <Widget>[
new FlatButton(
onPressed: () {
Navigator.pop(context);
},
child: new Text('CANCEL')),
new FlatButton(
onPressed: () {
_postAction(action, linkId).then((_) => setState(() {}));
Navigator.pop(context);
},
child: new Text('I CONFIRM')),
],
));
}

Answer 1

You can try this,this is just the idea..
class _SampleState extends State<Sample> {
bool isSuccessFromApi = false;
bool isLoading = false;
Widget popup() {
showDialog(context: context, builder: (builder) {
return AlertDialog(
content: !isSuccessFromApi ? Container(
child: Text('Are you Sure???'),
) : Container( child: isLoading ? CircularProgressIndicator() : Text('Success'),),
actions: <Widget>[
Text('Cancel'),
InkWell(child: Text('OK'), onTap: apiCall,)
],
);
});
}
void apiCall(){
setState(() {
isLoading = true;
});
//call the api
//after success or failure
setState(() {
isLoading = false;
isSuccessFromApi = true;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: popup(),
);
}
}