How can I add item number on the cart icon at at appBar icon in flutter? And how can I make it animate adding new item?

Question

I want to add item numbers on the cart icon in flutter like this in picture, and want to animate while adding new item to cart. My cart icon is in appBar.

Answer 1

It can be achieved by this piece of code in appBar.

appBar: new AppBar(

    actions: <Widget>[

      new Padding(padding: const EdgeInsets.all(10.0),

        child: new Container(
          height: 150.0,
          width: 30.0,
          child: new GestureDetector(
            onTap: () {
              Navigator.of(context).push(
                  new MaterialPageRoute(
                      builder:(BuildContext context) =>
                      new CartItemsScreen()
                  )
              );
            },

            child: new Stack(

              children: <Widget>[
                new IconButton(icon: new Icon(Icons.shopping_cart,
                  color: Colors.white,),
                    onPressed: null,
                ),
                list.length ==0 ? new Container() :
                new Positioned(

                    child: new Stack(
                      children: <Widget>[
                        new Icon(
                            Icons.brightness_1,
                            size: 20.0, color: Colors.green[800]),
                        new Positioned(
                            top: 3.0,
                            right: 4.0,
                            child: new Center(
                              child: new Text(
                                list.length.toString(),
                                style: new TextStyle(
                                    color: Colors.white,
                                    fontSize: 11.0,
                                    fontWeight: FontWeight.w500
                                ),
                              ),
                            )),


                      ],
                    )),

              ],
            ),
          )
        )

        ,)],