Flutter - 如何对列表进行勾选框筛选以缩小搜索范围

Question

I am very new to flutter and still learning. I am struggle on how to create a filter for a list of cars. Eg tick a box to only show red cars.

I do a little bit of searching but I can't seem to figure out how to do it. I did see a "where" method but struggling to make sence of it.

What is the the best way of doing this and can you please point me in the right direction. Can't get my head about this one.

Answer 1

So to create a filter for your list. Lets assume that you have a class for your car:

Class Car {
   final String carName;
   final String color;
   Car({this.carName, this.color});
}

And lets say you have some car objects:

List<Car> AllCars = [
    new Car(carName: "McQueen",color: "red"),
    new Car(carName: "Mater",color: "rusty"),
];

Now you create a statefulWidget for your list:

class ListPage extends StatefulWidget{
    @override
   _listPageState createState() => new _listPageState();
}

class _listPageState extends State<ListPage> {

    List<Car> _RedCars = null;

    @override
    void initState() {
        super.initState();
        _RedCars = AllCars.where((i) => i.color == "red").toList();
    }

    @override
    Widget build(BuildContext context) {
       return new Scaffold(
         body: new Container(
           child: new Text(
             "Boom!!! You are done. Now build your list on the page."
           ),
         ),
       );
     }
}

So, what you are trying to do can be achieved by this. Now all you have to do is to do it dynamic, show this list on your page. Remember the more your struggle the more you learn.