问题描述
每当我尝试通过单击 IconButton 来清除 TextField 时，尽管我的 TextField 已被清除，但我在调试控制台中收到一个未处理的异常警告。 此外，当我尝试向 TextField 添加新值时，我之前的值会自动显示在 TextField 中。 这是我的 Search_location UI 代码
import 'package:Flutter/material.dart';
import 'package:geoFlutterfire/geoFlutterfire.dart';
import 'package:geolocator/geolocator.dart';
import 'package:maps_app/models/place.dart';
import 'package:maps_app/services/location_api.dart';
import 'package:provider/provider.dart';
class SearchView extends StatefulWidget {
@override
_SearchViewState createState() => _SearchViewState();
}
class _SearchViewState extends State<SearchView> {
final _scrollController = ScrollController();
var latitude,longitude;
var con_width = 0.0;
var list_height = 0.0;
GeoFirePoint point;
GeoFlutterfire geo = GeoFlutterfire();
bool serviceEnabled;
LocationPermission permission;
@override
void initState() {
super.initState();
getCurrentLocation();
}
getCurrentLocation() async {
try {
final pos = await Geolocator.getCurrentPosition(
desiredAccuracy: LocationAccuracy.high);
setState(() {
latitude = pos.latitude;
longitude = pos.longitude;
});
} catch (e) {
print(e);
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: SearchInjector(
child: SafeArea(
child: Consumer<LocationApi>(
builder: (_,api,child) => SingleChildScrollView(
child: Container(
padding: const EdgeInsets.all(16),child: Column(
children: [
Container(
child: TextField(
onTap: () {
setState(() {
list_height = 56;
});
},controller: api.addressController,decoration: Inputdecoration(
prefixIcon: IconButton(
icon: Icon(Icons.my_location),onpressed: () {
// getCurrentLocation();
}),suffixIcon: IconButton(
icon: Icon(Icons.clear),onpressed: () {
setState(() {
api.addressController.clear();
con_width = 0.0;
list_height = 0.0;
});
}),border: OutlineInputBorder(
borderSide: BorderSide(
color: Colors.red,),borderRadius: BorderRadius.circular(50.0),labelText: 'Search Location',fillColor: Colors.grey[20],filled: true),onChanged: (value) {
setState(() {
con_width = 300.0;
});
api.places.clear();
api.handleSearch(value);
},AnimatedContainer(
duration: Duration(milliseconds: 20),height: list_height,color: Colors.blue[100].withOpacity(.3),width: MediaQuery.of(context).size.width,child: Column(
children: List.generate(1,(i) {
return ListTile(
onTap: () {
setState(() {
api.addressController.text = 'Your Location';
list_height = 0.0;
con_width = 0.0;
});
},title: Row(
children: [
Icon(Icons.my_location),SizedBox(
width: 5,Text(
'Your Location',style: TextStyle(
color: Colors.black,fontWeight: FontWeight.bold,],);
}))),AnimatedContainer(
duration: Duration(milliseconds: 20),height: con_width,child: StreamBuilder<List<Place>>(
stream: api.controllerOut,builder: (context,snapshot) {
if (snapshot.data == null) {
return Center(
child: Text('No data address found'));
}
final data = snapshot.data;
return Scrollbar(
controller: _scrollController,child: SingleChildScrollView(
controller: _scrollController,child: Container(
child: Builder(builder: (context) {
return Column(
children: [
Column(
children: List.generate(data.length,(index) {
final place = data[index];
return ListTile(
leading: Icon(Icons.home),onTap: () {
point = geo.point(
latitude: place.latitude,longitude: place.longitude);
setState(() {
api.addressController.text =
'${place.name},${place.subLocality},${place.country},${place.postalCode}';
con_width = 0.0;
list_height = 0.0;
});
},title: Text(
'${place.name},${place.locality},${place.postalCode} '),subtitle: Text(
'${place.adminArea},${place.country}'),);
})),);
}),);
}),)
],);
}
}
class SearchInjector extends StatelessWidget {
final Widget child;
const SearchInjector({Key key,this.child}) : super(key: key);
@override
Widget build(BuildContext context) {
return ChangeNotifierProvider(
create: (_) => LocationApi(),child: child,);
}
}
这是我在调试控制台中遇到的异常
Restarted application in 1,268ms.
E/MethodChannel#Flutter/textinput(29061): Failed to handle method call
E/MethodChannel#Flutter/textinput(29061): java.lang.indexoutofboundsexception: invalid selection start: 13
E/MethodChannel#Flutter/textinput(29061): at io.Flutter.embedding.engine.systemchannels.TextInputChannel$TextEditState.<init>(TextInputChannel.java:724)
E/MethodChannel#Flutter/textinput(29061): at io.Flutter.embedding.engine.systemchannels.TextInputChannel$TextEditState.fromJson(TextInputChannel.java:680)
E/MethodChannel#Flutter/textinput(29061): at io.Flutter.embedding.engine.systemchannels.TextInputChannel$1.onMethodCall(TextInputChannel.java:91)
E/MethodChannel#Flutter/textinput(29061): at io.Flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233)
E/MethodChannel#Flutter/textinput(29061): at io.Flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85)
E/MethodChannel#Flutter/textinput(29061): at io.Flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:818)
E/MethodChannel#Flutter/textinput(29061): at android.os.MessageQueue.nativePollOnce(Native Method)
E/MethodChannel#Flutter/textinput(29061): at android.os.MessageQueue.next(MessageQueue.java:336)
E/MethodChannel#Flutter/textinput(29061): at android.os.Looper.loop(Looper.java:174)
E/MethodChannel#Flutter/textinput(29061): at android.app.ActivityThread.main(ActivityThread.java:7697)
E/MethodChannel#Flutter/textinput(29061): at java.lang.reflect.Method.invoke(Native Method)
E/MethodChannel#Flutter/textinput(29061): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
E/MethodChannel#Flutter/textinput(29061): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
E/Flutter (29061): [ERROR:Flutter/lib/ui/ui_dart_state.cc(186)] Unhandled Exception: PlatformException(error,invalid selection start: 13,null,java.lang.indexoutofboundsexception: invalid selection start: 13
E/Flutter (29061): at io.Flutter.embedding.engine.systemchannels.TextInputChannel$TextEditState.<init>(TextInputChannel.java:724)
E/Flutter (29061): at io.Flutter.embedding.engine.systemchannels.TextInputChannel$TextEditState.fromJson(TextInputChannel.java:680)
E/Flutter (29061): at io.Flutter.embedding.engine.systemchannels.TextInputChannel$1.onMethodCall(TextInputChannel.java:91)
E/Flutter (29061): at io.Flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:233)
E/Flutter (29061): at io.Flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85)
E/Flutter (29061): at io.Flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:818)
E/Flutter (29061): at android.os.MessageQueue.nativePollOnce(Native Method)
E/Flutter (29061): at android.os.MessageQueue.next(MessageQueue.java:336)
E/Flutter (29061): at android.os.Looper.loop(Looper.java:174)
E/Flutter (29061): at android.app.ActivityThread.main(ActivityThread.java:7697)
E/Flutter (29061): at java.lang.reflect.Method.invoke(Native Method)
E/Flutter (29061): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
E/Flutter (29061): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
E/Flutter (29061): )
[38;5;244mE/Flutter (29061): #0 JSONMethodCodec.decodeEnvelope[39;49m
[38;5;244mE/Flutter (29061): #1 MethodChannel._invokeMethod[39;49m
E/Flutter (29061): <asynchronous suspension>
E/Flutter (29061):
解决方法
问题是控制器的清除。
代替
api.addressController.clear();
试试：
WidgetsBinding.instance.addPostFrameCallback((_) => api.addressController.clear());
我认为您正在尝试访问不存在的索引，请尝试检查您的列表大小。