问题
I am trying to implement input search feature wherein typing a search text will display suggested text and user can select relevant text from list and hit search button to proceed to corresponding screen. The suggested text is in local json and I added it under under assets/ folder and in pubspec.yaml.
The search textfield is:
The code for above is:
new TextField(
style: new TextStyle(
color: Colors.white,
fontSize: 16.0),
cursorColor: Colors.green,
decoration: new InputDecoration(
suffixIcon: Container(
width: 85.0,
height: 60.0,
color: Colors.green,
child: new IconButton(
icon: new Image.asset('assets/search_icon_ivory.png',color: Colors.white, height: 18.0,),
onPressed: () {
},
),
),
fillColor: Colors.black,
contentPadding: new EdgeInsets.fromLTRB(10.0, 30.0, 10.0, 20.0),
filled: true,
hintText: 'What Do You Need Help With?',
hintStyle: new TextStyle(
color: Colors.white
)
)
)
The local json data sample is:
I want to achieve above using autocomplete_textfield package which I've installed and imported and referring this example.
I would like to know how to get started with this and integrate parsing from local json, hook that data using autocomplete_textfield package to achieve my goal. I haven't done parsing json in flutter yet so looking for guidance on how to do that.
The end result I am looking for is like this:
***************** Edit **************
I am now able to parse data from local json and display it in a listView using a demo app. For it, I created a new model class `services.dart' as below:
class Categories {
String serviceCategory;
String servCategoryDesc;
int id;
String autocompleteterm;
String category;
String desc;
Categories({
this.serviceCategory,
this.servCategoryDesc,
this.id,
this.autocompleteterm,
this.category,
this.desc
});
factory Categories.fromJson(Map<String, dynamic> parsedJson) {
return Categories(
serviceCategory:parsedJson['serviceCategory'] as String,
servCategoryDesc: parsedJson['serviceCategoryDesc'] as String,
id: parsedJson['serviceCategoryId'],
autocompleteterm: parsedJson['autocompleteTerm'] as String,
category: parsedJson['category'] as String,
desc: parsedJson['description'] as String
);
}
}
Used builder function to retrieve and display value in listview as below:
@override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text("Load local JSON file"),
),
body: new Container(
child: new Center(
// Use future builder and DefaultAssetBundle to load the local JSON file
child: new FutureBuilder(
future: DefaultAssetBundle
.of(context)
.loadString('assets/services.json'),
builder: (context, snapshot) {
// Decode the JSON
Map data = json.decode(snapshot.data
.toString());
print(data);
final List<Categories> items = (data['data'] as List).map((i) => new Categories.fromJson(i)).toList();
for (final item in items) {
print(item.category);
return new ListView.builder(
itemBuilder: (BuildContext context, int index) {
return new Card(
child: new Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
new Text('Service Category: ' + items[index].category),
new Text('Category' + items[index].categoryDesc),
new Text('Auto complete term' + items[index].autocompleteterm),
new Text('Desc' + items[index].desc)
],
),
);
},
);
}
}
)
)
)
);
}
}
In my target app, added required code that uses autocomplete_textfield package that shows a static list of suggestions as of now :
@override
Widget build(BuildContext context) {
textField = new AutoCompleteTextField<String>
(style: new TextStyle(
color: Colors.white,
fontSize: 16.0),
decoration: new InputDecoration(
suffixIcon: Container(
width: 85.0,
height: 60.0,
color: Colors.green,
child: new IconButton(
icon: new Image.asset('assets/search_icon_ivory.png',color: Colors.white,
height: 18.0,),
onPressed: (){},
),
),
fillColor: Colors.black,
contentPadding: new EdgeInsets.fromLTRB(10.0, 30.0, 10.0, 20.0),
filled: true,
hintText: 'What Do You Need Help With ?',
hintStyle: new TextStyle(
color: Colors.white
)
),
submitOnSuggestionTap: true,
clearOnSubmit: true,
textChanged: (item){
currentText = item;
},
textSubmitted: (item) {
setState(() {
currentText = item;
});
},
key: key,
suggestions: suggestions,
itemBuilder: (context, item) {
return new Padding(
padding: EdgeInsets.all(8.0), child: new Text(item));
},
itemSorter: (a, b) {
return a.compareTo(b);
},
itemFilter: (item, query) {
return item.toLowerCase().startsWith(query.toLowerCase());
});
Column body = new Column(children: [
new GestureDetector(
child: new ListTile(
title: textField,
onTap: () {
setState(() {
if (currentText != "") {
added.add(currentText);
textField.clear();
currentText = "";
}
});
}
)
)
]
);
body.children.addAll(added.map((item) {
return new ListTile(
title: new Text(item)
);
}));
return Scaffold(
resizeToAvoidBottomPadding: false,
backgroundColor: Color(0xFF13212C),
appBar: AppBar(
title: Text(''),
),
drawer: appDrawer(),
body: new Center(
child: new Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
new Column(
children: <Widget>[
textField
Above code shows in UI as below:
I now would like to know how to hook the builder function retrieving json data in my target app, so that instead of static list of strings, the dropdown would show suggestions from json (as posted in my original question's screenshot).
回答1:
If you found doing this manually it too much, this is actually a flutter package that does this. There are two examples on the package site too.
Do be warned, this is currently a bug in the package (I have raised a PR to fix it but the package owner has been too busy to review any PR recently). Depending on how you use it, the bug may not affect you.
来源：https://stackoverflow.com/questions/53429467/how-to-hook-up-data-from-local-json-to-achieve-search-with-autocomplete-text-in