问题
When clicking the add button, the same widget is replicated. The widget contains the list of checkboxes that are multi selectable. I am able to replicate the widget but I got problem to handle the checkboxes according to the index of the widget. In image below the checkbox checked state is replicated along with the new add widget.
I have implemented as follows:
Build the widget according to the addbutton click
ListView.builder(
itemCount: counting,
shrinkWrap: true,
physics: const NeverScrollableScrollPhysics(),
itemBuilder: (_, index) {
return _buildLayout(context, index);
});
//counting is number of **blueplus** icon is clicked
Widget _buildLayout(BuildContext context, int i) {
return Column(
children: <Widget>[
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Text(
addContainer,
style: TextStyle(color: Colors.blueGrey),
),
Container(
width: 64.0,
alignment: Alignment.center,
child: IconButton(
onPressed: () => {i == 0 ? addRow(i) : deleteRow(i)},
icon: Icon(
i == 0
? Icons.add_circle_outline
: Icons.remove_circle_outline,
color: i == 0 ? Theme.of(context).primaryColor : Colors.red,
)),
),
],
),
_buildCheckBoxes()
],
);
}
Widget _buildCheckBoxes() {
return
Container(
width: MediaQuery.of(context).size.width,
child: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
InkWell(
onTap: () {
showHide();
},
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Text(
productionmareketway,
style: TextStyle(
fontSize: 18, fontWeight: FontWeight.bold),
),
showHidee
? Icon(Icons.keyboard_arrow_up)
: Icon(Icons.keyboard_arrow_down)
])),
SizedBox(
width: 20,
),
showHidee
? ListView.builder(
shrinkWrap: true,
physics: const NeverScrollableScrollPhysics(),
itemCount: widget.responseMarket.length,
itemBuilder: (ctx, i) {
return _buildSingleCheckBox(
context,
widget.responseMarket[i].name,
widget.responseMarket[i].isChecked,
widget.responseMarket[i].id,
widget.responseMarket[i].identifier,
i);
})
: Container()
])
);
}
Widget _buildSingleCheckBox(BuildContext context, String name, bool isChecked,
int i, String identifier, int j) {
return Container(
child: new CheckboxListTile(
title: new Text(name),
value: isChecked,
activeColor: Theme.of(context).primaryColor,
checkColor: Colors.white,
onChanged: (bool value) {
setState(() {
widget.responseMarket[i].isChecked = value;
print(value);
print(i);
widget._onChecked(
value,
widget.responseMarket[i].id,
widget.responseMarket[i].name,
widget.responseMarket[i].identifier,
counting);
});
},
),
);
}
Add and delete widget function
addRow(int i) {
setState(() {
counting = counting + 1;
});
}
deleteRow(int i) {
setState(() {
counting = counting - 1;
});
}
My callback function
onMarketChecked(var value, int i, String name, String identifier, int j) {
setState(() {
if (responseMarket[i].isChecked == true) {
nonMarketRepated.add(name);
} else {
nonMarketRepated.remove(responseMarket[i].name);
}
});
}
回答1:
This issue is because you control all replica by counting and widget.responseMarket. If you want all replicas work individually, you need to Replica it actually.
I suggest to create a new StatefulWidget to replace _buildSingleCheckBox() & _buildCheckBoxes() function. I also put showHidee inside it.
class CheckBoxesWidget extends StatefulWidget {
final responseMarket;
CheckBoxesWidget({this.responseMarket, Key key}) : super(key: key);
@override
_CheckBoxesWidgetState createState() => _CheckBoxesWidgetState();
}
class _CheckBoxesWidgetState extends State<CheckBoxesWidget> {
bool showHidee;
@override
void initState() {
showHidee = true;
super.initState();
}
@override
Widget build(BuildContext context) {
return Container(
width: MediaQuery.of(context).size.width,
child: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
InkWell(
onTap: () {
showHide();
},
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Text(
'productionmareketway',
style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
),
showHidee
? Icon(Icons.keyboard_arrow_up)
: Icon(Icons.keyboard_arrow_down)
],
),
),
SizedBox(
width: 20,
),
if (showHidee)
Column(
children: widget.responseMarket
.map(
(e) => CheckboxListTile(
title: Text(e.name),
value: e.isChecked,
activeColor: Theme.of(context).primaryColor,
checkColor: Colors.white,
onChanged: (bool value) {
setState(() {
e.isChecked = value;
});
},
),
)
.toList(),
),
],
),
);
}
void showHide() {
setState(() {
showHidee = !showHidee;
});
}
}
Second, beyond control the replica by counting, you should use a List to store all replica of responseMarket in the original class.
List<List<Market>> responseMarkets;
@override
void initState() {
responseMarkets = [widget.responseMarket];
super.initState();
}
...
@override
Widget build(BuildContext context) {
return ListView.builder(
itemCount: responseMarkets.length,
itemBuilder: (_, index) {
return _buildLayout(context, index);
});
}
...
Widget _buildLayout(BuildContext context, int i) {
...
// replace _buildCheckBoxes() with this line
CheckBoxesWidget(responseMarket: responseMarkets[i],),
...
}
Finally, you have to modify the addRow, deleteRow function. Each time create a new ResponseMarkets Object.
addRow(int i) {
setState(() {
responseMarkets.add(responseMarkets[0]
.map((e) => ResponseMarkets(
id: e.id,
name: e.name,
identifier: e.identifier,
isChecked: e.isChecked,
))
.toList());
});
}
deleteRow(int i) {
setState(() {
responseMarkets.removeAt(i);
});
}
来源：https://stackoverflow.com/questions/64108301/handle-the-list-of-dynamic-checkboxes-when-the-widget-is-added-on-button-click-i