I have a ListView.builder
which returns a ListTile
. The itemCount
is set to min(_selectedEvents.length, 3)
. So a maximum of 3 ListTile
s is being returned with a backgroundColor
of Colors.grey[200]
.
I want to set the color to Colors.red
for a single ListTile
when it is pressed. I set selected: _selectedListtileController
(a var
that I created) and with onTap
this is being set to true, which changes the color to red.
But the problem is that the red color is set for all the ListTile
s and not for a single one. Also creating 3 separate controllers is not an option because I return them in a ListTile
and I can only pass 1 controller.
How do I set the color of a separate ListTile
whenever the ListTile
is pressed?
Thanks in advance!
If you'd like more than one ListTile
to be selectable, we could define a List<int>
where to save the indexes
of selected ListTile
s:
// StatefulWidget is required
List<int> _selectedTiles = [];
And use the following functions to toggle the selected state of a specific ListTile
:
void toggleSelectedListTile(int index) {
if (_selectedTiles.contains(index))
setState(() => _selectedTiles.remove(index));
else
setState(() => _selectedTiles.add(index));
}
A ListTile
Widget
has the selected
property, which we can take advantage of:
ListTile(
selected: _selectedTiles.contains(index),
selectedTileColor: Colors.red,
title: Text('List tile $index'),
onTap() { toggleSelectedListTile(index); },
)
Therefore, a full example snippet of this solution would be:
class HomeWidget extends StatefulWidget {
HomeWidget({ Key key }) : super(key: key);
@override
_HomeWidgetState createState() => _StatefulWidgetExampleState();
}
class _HomeWidgetState extends State<StatefulWidgetExample> {
List<int> _selectedTiles = [];
void toggleSelectedListTile(int index) {
if (_selectedTiles.contains(index))
setState(() => _selectedTiles.remove(index));
else
setState(() => _selectedTiles.add(index));
}
Widget _buildListTile(int index) {
return ListTile(
selected: _selectedTiles.contains(index),
selectedTileColor: Colors.red,
title: Text('List tile $index'),
onTap() { toggleSelectedListTile(index); },
);
}
@override
Widget build(BuildContext context)
return Scaffold(
body: new ListView.builder
(
itemCount: 3,
itemBuilder: (BuildContext ctxt, int index) => _buildListTile(index),
),
);
}
Create an empty map at the top of the class
final _isSelected = Map();
@override
Widget build(BuildContext context) {
on your ListView.builder
ListView.builder(
itemCount: _selectedEvents.length,
itemBuilder: (context, index) {
//add this line to initiate
if (!_isSelected.containsKey(index)) // important
_isSelected[index] = false;
return ListTile(
...
...
// and this line to check listTile is selected or not
selected: _isSelected[index],
tileColor: Colors.grey[200],
selectedTileColor: Colors.red,
onTap: () {
setState(() => _isSelected[index] = !_isSelected[index] );
},
);
},
),
or you can create your selected logic at initState()
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