48 lines
900 B
Dart
48 lines
900 B
Dart
import "package:flutter/material.dart";
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enum SearchState {
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empty,
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searching,
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notEmpty,
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}
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class IndexOfStackNotifier with ChangeNotifier {
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int _prevIndex = 0;
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int _index = 0;
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bool _isSearchQueryEmpty = true;
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SearchState _searchState = SearchState.empty;
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static IndexOfStackNotifier? _instance;
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IndexOfStackNotifier._();
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factory IndexOfStackNotifier() => _instance ??= IndexOfStackNotifier._();
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set isSearchQueryEmpty(bool value) {
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_isSearchQueryEmpty = value;
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setIndex();
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}
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set searchState(SearchState value) {
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_searchState = value;
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setIndex();
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}
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setIndex() {
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_prevIndex = _index;
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if (_isSearchQueryEmpty) {
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_index = 0;
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} else {
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if (_searchState == SearchState.empty) {
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_index = 2;
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} else {
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_index = 1;
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}
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}
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_prevIndex != _index ? notifyListeners() : null;
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}
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get index => _index;
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}
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