useStateList.md

useStateList

Provides handles for circular iteration over states list. Supports forward and backward iterations and arbitrary position set.

Installation

dependencies:
  flutter_use: ^0.0.2

Usage

class Sample extends HookWidget {
  @override
  Widget build(BuildContext context) {

    final list = ['first', 'second', 'third', 'fourth', 'fifth'];
    final stateList = useStateList(list);
    final stateAtController = useTextEditingController();
    final stateController = useTextEditingController();

    return Column(
      children: [
        Text(stateList.list.toString()),
        Text(
          "${stateList.list.isNotEmpty ? stateList.state : null} [index: ${stateList.currentIndex}]"),
        Row(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            ElevatedButton(
              onPressed: () => stateList.prev(),
              child: const Text('prev')),
            ElevatedButton(
              onPressed: () => stateList.next(),
              child: const Text('next')),
          ],
        ),
        TextFormField(
          controller: stateAtController,
          decoration: const InputDecoration(
            labelText: 'set state by index',
          ),
        ),
        ElevatedButton(
          onPressed: () {
            stateList.setStateAt(int.parse(stateAtController.text));
          },
          child: const Text('set state by index')),
        TextFormField(
          controller: stateController,
          decoration: const InputDecoration(
            labelText: 'set state by value',
          ),
        ),
        ElevatedButton(
          onPressed: () {
            stateList.setState(stateController.text);
          },
          child: const Text('set state by value'),
        ),
      ],
    );
  }
}

Reference

UseStateList<T> useStateList<T>([List<T> stateSet = const []])

If stateSet changed, became shorter than before and currentIndex left in shrunk gap - the last element of list will be taken as current.

• state: T — current state value;
• currentIndex: int — current state index;
• prev(): void — switches state to the previous one. If first element selected it will switch to the last one;
• next(): void — switches state to the next one. If last element selected it will switch to the first one;
• setStateAt(int newIndex): void — set the arbitrary state by index. Indexes are looped.
  4ex: if list contains 5 elements, attempt to set index 9 will bring use to 5th element, in case of negative index it will set to the 0th.
• setState(T state): void — set the arbitrary state value that exists in stateSet. In case new state does not exists in stateSet an Error will be thrown.