Problems with child and brackets - flutter

Question

Morning guys,
I´ve problems with bracket and childs. When I combined Containers, Center and Stack and so on , it shows me most of the time red lines under some words. It´s always luck when I can solve it. Here is a part of my code where I will show you what I mean..
The problem is the first child after children:
Widget build(BuildContext context) {
return Scaffold(
body: Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage("assets/kreis.jpeg"), fit: BoxFit.fill)),
child: Stack(
children: <Widget>[
child:Container(
Center(
Visibility(
child: Text("Gone"),
visible: visibleT,
child:Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/T.jpeg"),fit: BoxFit.fill),
),
),
),
Visibility(
child: Text("Gone") ,
visible: visibleB,
child:Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/B.png"),fit: BoxFit.fill),
),
),
),
Visibility(
child:Text("Gone"),
visible: visibleH,
child: Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/h.png"),fit: BoxFit.fill),
),
),
)
),
Positioned(
right: 150,
top: 150,
width: 60,
height: 70,
child: FloatingActionButton(
onPressed:
_listen,
// setState(() { searchWord="Tinte";});
// getText();
child: Icon(_isListening ? Icons.mic : Icons.mic_none),
)
),
Positioned(
left: 100,
bottom: 10,
child: Container(
width: MediaQuery.of(context).size.width * 0.8,
decoration: BoxDecoration(
color: Colors.cyanAccent[100],
borderRadius: BorderRadius.circular(6.0),
),
padding: EdgeInsets.symmetric(
vertical: 8.0,
horizontal: 12.0,
),
child: Text(
_text,
style: TextStyle(fontSize: 24.0),
)
)
)
)
]
)
)
);
}
this is not the end, but I think this was the critical part

Answer 1

You must consider the tree structure in nested widgets!
Fixed:
Widget build(BuildContext context) {
return Scaffold(
body: Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage("assets/kreis.jpeg"), fit: BoxFit.fill)),
child: Stack(children: <Widget>[
Container(
child: Center(
child: Visibility(
replacement: Text("Gone"),
visible: visibleT,
child: Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/T.jpeg"), fit: BoxFit.fill),
),
),
))),
Visibility(
replacement: Text("Gone"),
visible: visibleB,
child: Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/B.png"), fit: BoxFit.fill),
),
),
),
Visibility(
replacement: Text("Gone"),
visible: visibleH,
child: Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/h.png"), fit: BoxFit.fill),
),
),
),
Positioned(
right: 150,
top: 150,
width: 60,
height: 70,
child: FloatingActionButton(
onPressed: _listen,
// setState(() { searchWord="Tinte";});
// getText();
child: Icon(_isListening ? Icons.mic : Icons.mic_none),
)),
Positioned(
left: 100,
bottom: 10,
child: Container(
width: MediaQuery.of(context).size.width * 0.8,
decoration: BoxDecoration(
color: Colors.cyanAccent[100],
borderRadius: BorderRadius.circular(6.0),
),
padding: EdgeInsets.symmetric(
vertical: 8.0,
horizontal: 12.0,
),
child: Text(
_text,
style: TextStyle(fontSize: 24.0),
)))
])));
}

Answer 2

Some widget only allow multiple children, in your code it look like you have multiple child for widget which can only handle one child only. Like stack allow multiple child but container do not allow multiple child. Please check all container code there is multiple child in the container widget.
Edit:
Error free code, please share design for the app so all widgets could be properly aligned.
here is the code
bool _isListening = false;
bool visibleT = true;
bool visibleH = true;
bool visibleB = true;
#override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage("assets/images/logo.png"), fit: BoxFit.fill)),
child: Stack(
children: [
Container(
child: Center(
child: Visibility(
visible: visibleT,
child: Column(
children: [
Text("Gone"),
Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/images/logo.png"),
fit: BoxFit.fill),
),
),
],
),
),
),
),
Container(
child: Center(
child: Visibility(
visible: visibleB,
child: Column(
children: [
Text("Gone"),
Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/images/logo.png"),
fit: BoxFit.fill),
),
),
],
),
),
),
),
Container(
child: Center(
child: Visibility(
visible: visibleH,
child: Column(
children: [
Text("Gone"),
Container(
height: 150,
width: 150,
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
image: AssetImage("assets/images/logo.png"),
fit: BoxFit.fill),
),
),
],
),
),
),
),
Positioned(
left: 100,
bottom: 10,
child: Container(
width: MediaQuery.of(context).size.width * 0.8,
decoration: BoxDecoration(
color: Colors.cyanAccent[100],
borderRadius: BorderRadius.circular(6.0),
),
padding: EdgeInsets.symmetric(
vertical: 8.0,
horizontal: 12.0,
),
child: Text(
"Some Text",
style: TextStyle(fontSize: 24.0),
)))
],
),
),
floatingActionButton: Positioned(
right: 150,
top: 150,
width: 60,
height: 70,
child: FloatingActionButton(
child: Icon(_isListening ? Icons.mic : Icons.mic_none),
),
),
);
}