How to refresh widget? - flutter

Question

I want to "refresh" my widget after i upload a file.
new Container(
child: _profileAvatar(),
width: 150.0,
height: 150.0,
),
Widget _profileAvatar(){
if(!hasProfilImage){
return CircleAvatar(
radius: 30.0,
backgroundImage:
new ExactAssetImage('assets/images/default_profile.png'),
backgroundColor: Colors.transparent,
);
}else {
return CircleAvatar(
radius: 30.0,
backgroundImage:
NetworkImage( "${Configuration.url}assets/profileImage/${userProfilImage}"),
backgroundColor: Colors.transparent,
);
}
}
and here is how i upload a file
Future getImage() async {
var image = await ImagePicker.pickImage(source: ImageSource.gallery);
setState(() {
if(image != null) {
_image = image;
hasProfilImage = true;
_upload();
}
});
}
for now after the upload process finished, i need to re open this "page" to see the new image.
How can i show the new image immediately after the upload process finish?
thanks in advance
Here is what i try so far , but still no help
Future getImage() async {
var image = await ImagePicker.pickImage(source: ImageSource.gallery);
setState(() {
if(image != null) {
_image = image;
_upload().then((isSuccess){
setState(() {
hasProfilImage = true;
});
});
}
});
}
here is my full script https://pastebin.com/59UfYa2P

Answer 1

As you are working with flutter you can use StatefulWidget which has a setState method. whenever you want to update the data put that data after processing. It will automatically update at its position.
setState(() {});
If you have the API call or function in another widget you can use callback to update the widget.
If you want to update the previous widget after the processing the on the next widget Here is the callback
_navigateAndDisplayDriverSelection(
BuildContext context, String userId, String driveId) async {
final driverModal = await Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Drivers(userId: userId, driveId: driveId)),
);
setState(() {});
}

Answer 2

Your Upload function probably returns a Future with some value whether the image is successfully uploaded or not.
Future getImage() async {
var image = await ImagePicker.pickImage(source: ImageSource.gallery);
if(image != null) {
_image = image;
_upload().then((isSuccess){
// once upload is completed then, call setState and it will rebuild the widget tree and update the view.
setState(() {
hasProfilImage = true;
});
});
}
}

Answer 3

If you don't want to pass down your setState method through your widget tree, you can also use ScopedModels.
This page has a brief example of how to implement a scopedmodel:
https://pub.dev/packages/scoped_model
Just know that every time you call notifylisteners(), everything underneath ScopedModelDescendant gets rebuild.
The issue you are facing is one of state-management, and there are also alternative solutions for this problem: https://flutter.dev/docs/development/data-and-backend/state-mgmt