Q:

How do I add dynamically widgets to a subtitle? ( for ListTile)

I'm trying to add Chips to the ListTile subtitle, so that when the listTile is created via a ListView.builder, depending on the user's selection, they can have or see multiple chips in the subtitle. 
ListView.builder(

      scrollDirection: Axis.vertical,
      itemCount: myShoppingBasketList.length,
      itemBuilder: (ct, shoppingListViewBuilderItemInteger)
      {

       return Card(
            child: ListTile(key: UniqueKey(),
                //dense: true,
                leading: ...,
                title: ...
                subtitle: Wrap(<add chips here)...
                onTap: () 
                {

// Code to add new chips depending on selection

                }

        })

So - how could I dynamically += add to a Wrap widget.  When I say
+=

What I'm hoping for is that if a Chip was like a String, then I'd like something like:
Wrap(SomeChipContainerWidget = SomeChipContainerWidget+ newChipWidget))

Do you see my problem?? 
So let's say the subTitle was a Text widget, then the String text inside could be:
Text(stringVar += stringVar + newString)
I have tried EVERYTHING - You cannot imagine.  I've looked at Expansion Tiles - does't work, Animated, etc..
Any help will be really appreciated.  Even sympathy. 

A:

Declare a List and add a Chip to the List as per your requirement. 
Example Code:
List<Chip> chips = []; // Global Variable (Add a chip by default)
[...]
ListView.builder(
      scrollDirection: Axis.vertical,
      itemCount: myShoppingBasketList.length,
      itemBuilder: (ct, shoppingListViewBuilderItemInteger)
      {
       return Card(
            child: ListTile(key: UniqueKey(),
                //dense: true,
                leading: [...],
                title: [...]
                subtitle: Wrap(children: <Widget>[chips])...
                onTap: () 
                {
                   setState((){
                       chips.add(
                        Chip() //Your new chip
                        );
                    });
                }
        })

