Syntax highlighter doesn't expand to show all code - flutter

Question

I am trying to come up with a code editor which takes input from a text form field and shows the output on a Rich Text widget using DartSyntaxHighlighter.
While it works fine for a short snippet of code, it doesn't show all the code for a larger snippet. Here's what I've done so far :
class CodeEditorWidget extends StatefulWidget {
CodeEditorWidget();
#override
_ContentWidgetState createState() {
return _ContentWidgetState();
}
}
class _ContentWidgetState extends BaseState<CodeEditorWidget> {
String _currentCode = "";
#override
void initializeData() {
_currentCode = "class HelloWorld {\n"
"public static void main() {\n"
"System.out.println(\"Hello again\");\n"
"}\n"
"}";
_contentController.addListener(() {
_currentCode = _contentController.value.text;
setState(() {
});
});
}
#override
Widget build(BuildContext context) => _buildContent();
Widget _buildContent() {
//return _buildBody();
userState = AppStateWidget.of(context).userState;
return _buildBody();
}
Scaffold _buildBody() => Scaffold(
key: _scaffoldLoginKey,
appBar: buildAppBar("Code Editor"),
body: _buildCodeEditor(),
floatingActionButtonLocation: FloatingActionButtonLocation.endFloat,
floatingActionButton: _buildFab(),
);
_buildCodeEditor() => Card(
margin: const EdgeInsets.fromLTRB(BaseState.horizontalMargin, 0, BaseState.horizontalMargin, 0),
child: Column(
children: <Widget>[
Expanded(
child: _buildCodeView()//buildSyntaxCodeBlock(_currentCode, 12)//_buildCodeView(),
),
_buildInputContainer()
],
),
);
_buildCodeView() => SingleChildScrollView(
scrollDirection: Axis.vertical,
child: Padding(
padding: const EdgeInsets.all(16.0),
child: Container(
width: double.infinity,
height: double.maxFinite,
padding: EdgeInsets.all(12),
decoration: BoxDecoration(color: Colors.black),
child: RichText(
text: TextSpan(
style: TextStyle(fontFamily: 'VarelaRound-Regular', fontSize: 12),
children: <TextSpan>[
DartSyntaxHighlighter(SyntaxHighlighterStyle.darkThemeStyle()).format(_currentCode)
],
),
),
),
),
);
Container _buildInputContainer() {
return Container(
color: Colors.grey,
padding: EdgeInsets.all(8),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
_buildInputLayout(),
],
),
);
}
_buildInputLayout() => Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[_buildTextForm()],
);
Widget _buildTextForm() => Flexible(
child: Container(
color: Colors.white,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: TextFormField(
style: buildTextStyleBlack(16),
decoration: InputDecoration.collapsed(hintText: "Type here..."),
maxLines: 10,
validator: _validateEmptyCode,
controller: _contentController,
keyboardType: TextInputType.multiline,
onSaved: (String contentString) {
//_currentCode = contentString;
},
),
),
),
);
String _validateEmptyCode(String value) {
return value.isEmpty ? "Required" : null;
}
var _contentController = TextEditingController();
_buildFab() => FloatingActionButton(
onPressed: () {
setState(() {
});
},
child: Icon(Icons.add),
foregroundColor: Colors.white,
backgroundColor: Colors.green,
);
var _scaffoldLoginKey = GlobalKey<ScaffoldState>();
_showSnackBar(String message) => _scaffoldLoginKey.currentState
.showSnackBar(SnackBar(content: Text(message, style: buildTextStyle(16),)));
}
Here's a screen shot for reference :
This is a web page I am trying to build in flutter.

Answer 1

For me, this piece of code is doing what you are trying to acheive.
TextEditingController text1Controller = new TextEditingController();
TextEditingController text2Controller = new TextEditingController();
#override
Widget build(BuildContext context) {
Size screenSize = MediaQuery.of(context).size;
return new Scaffold(
backgroundColor: Colors.white,
appBar: new PreferredSize(
preferredSize: new Size(screenSize.width, 55.0),
child: new AppBar(
elevation: 5.0,
title : new Text(
"Code Editor",
style: new TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 18.0)),
centerTitle: true,
backgroundColor: Colors.blue,
),
),
body: Container(
child: Column(
children: <Widget>[
new Padding(padding: EdgeInsets.only(bottom: 20.0, top: 20.0)),
new TextField(
onChanged: (text) {
setState(() {
text2Controller.text = text;
});
},
controller: text1Controller,
keyboardType: TextInputType.text,
autofocus: false,
decoration: InputDecoration(
contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
focusedBorder: OutlineInputBorder(borderSide: const BorderSide(color: Colors.black, width: 2.0)),
),
),
new Padding(padding: EdgeInsets.only(bottom: 20.0)),
new TextField(
controller: text2Controller,
keyboardType: TextInputType.text,
autofocus: false,
decoration: InputDecoration(
contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
focusedBorder: OutlineInputBorder(borderSide: const BorderSide(color: Colors.black, width: 2.0)),
),
)
],),),
);
}