I'm using imagepicker to capture an image, I've implemented sound null safety and I am passing it to a Second page but when trying to display image on 2nd page I'm getting error: The argument type 'File?' can't be assigned to the parameter type 'File'.
please assist, thank you :)
bellow are the code snippets
// 1st page : variable statements and getImage function
File? _image;
final _picker = ImagePicker();
Future getImage() async {
Map<Permission, PermissionStatus> statuses = await [
Permission.camera,
].request();
if (await Permission.camera.request().isGranted) {
PickedFile? _pickedFile = await _picker.getImage(
source: ImageSource.camera, maxHeight: 1920, maxWidth: 1080);
setState(() {
_image = File(_pickedFile!.path);
});
}}
// 1st page: button executing the getImage function
ElevatedButton(
onPressed: () async {
await getImage();
Navigator.push(context, MaterialPageRoute(builder: (context) {
return SecondPage(image: _image);
})); //callback
},
// 2nd page class
class SecondPage extends StatefulWidget {
File? image;
//c'tor
SecondPage({
Key? key,
@required this.image,
}) : super(key: key);
@override
_SecondPageState createState() => _SecondPageState();
}
// in body of 2nd page where error is displayed
SizedBox(
width: 300,
height: 265,
child: Image.file(widget.image),
),
The error you get came from null-safety, the type File?
means that it could be either a File
, or null
, but your variable only accepts a File
, and no null
value.
For this, you can "force" the use of 'non-null' variable by adding a !
at the end of your variable, but be careful when doing this.
Image.file(widget.image!),
You can learn more about null-safety syntax and principles on the official documentation: https://flutter.dev/docs/null-safety.
https://api.flutter.dev/flutter/material/DropdownButton-class.html.