How to handle multiple checkboxes from a Listview.builder?

Question

I have a ListView.builder which returns a checkbox and its label. This listview will return a list of checkboxes and labels which will be displayed on the screen. Currently, I'm just creating a global variable isChecked and changing the value of the checkbox with onChanged callback and this value. But it changes the values of all the checkboxes present on the screen.

I need a way to handle each checkbox individually without modifying other checkbox values. And also keep a count of the ticked checkboxes. I'm using a checkboxtile widget for this.

Answer 1

As you have not shared any code, i assume you have a single variable isChecked. But you should have a list of isChecked so that you can store them separately.

List<bool> isChecked = List<bool>.generate(length, index => false);

ListView.builder(
  itemCounter: length,
  itemBuilder: (BuildContext context,int index){ 
      return Checkboxtile ( 
        title: 'label', 
        value: isChecked[index],
        onChanged: (newValue) {
          setState(() {
            isChecked[index] = newValue;
          }); 
        },
      ); 
    } 

To calculate the no. of the ticked checkBox:

int _checkedBox = 0;
for (int i = 0; i < isChecked.length; i++) 
  if (isChecked[i])
    _checkedBox++;