- Edited
Merhaba arkadaşlar, Firebase’den veri çekerken aşağıdaki hatayı alıyorum, bir türlü çözemedim, çözümü nedir?
The function can’t be unconditionally invoked because it can be ‘null’.
Try adding a null check (‘!’).
Kodlarım aşağıdadır. (Kalın yazılan yerler hata veriyor.)
return Scaffold(
appBar: AppBar(
title: Text("Personel Listesi"),
backgroundColor: Colors.redAccent[400],
actions: <Widget>[
IconButton(
icon: Icon(Icons.home),
onPressed: () {
Navigator.pushAndRemoveUntil(
context,
MaterialPageRoute(builder: (_) => WelcomePage()),
(route) => true);
},
),
],
),
body: Container(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Center(
child: Column(
children: [
StreamBuilder<QuerySnapshot>(
stream: staffRef.snapshots(),
builder: (BuildContext context, AsyncSnapshot asyncSnapshot) {
if (asyncSnapshot.hasError) {
return Center(
child: Text(
"Bir hata oluştu, lütfen tekrar deneyiniz."));
} else {
if (asyncSnapshot.hasData) {
List<DocumentSnapshot> listStaff =
asyncSnapshot.data.docs;
return Flexible(
child: ListView.builder(
itemBuilder: (context, index) {
return Card(
elevation: 20,
color: Colors.greenAccent[200],
child: ListTile(
trailing: IconButton(
icon: Icon(Icons.delete),
onPressed: () async {
await listStaff[index]
.reference
.delete();
},
),
title: Text(
**'${listStaff[index].data()['nameSurname']}',**
style: TextStyle(fontSize: 20),
),
subtitle: Column(
children: [
Row(
mainAxisAlignment:
MainAxisAlignment.start,
children: [
Text(
**'${listStaff[index].data()['tip']}',**
style: TextStyle(fontSize: 14),
),
],
),
Row(
mainAxisAlignment:
MainAxisAlignment.start,
children: [
Text(
**'${listStaff[index].data()['mail']}',**
style: TextStyle(fontSize: 14),
),
],
),
Row(
mainAxisAlignment:
MainAxisAlignment.start,
children: [
Text(
**'${listStaff[index].data()['phone']}',**
style: TextStyle(fontSize: 14),
),
],
),
],
),
),
);
},
itemCount: listStaff.length),
);
} else {
return Center(
child: CircularProgressIndicator(),
);
}
}
},
),
],
),
),
),
),
);
}
}
