Делегации

class CustomSearchDelegateFerns extends SearchDelegate {

  @override
  List<Widget> buildActions(BuildContext context) {
    return [
      IconButton(
          onPressed: (){
            query = '';
          },
          icon: const Icon(Icons.clear))
    ];
  }

  @override
  Widget buildLeading(BuildContext context) {
    return IconButton(
        onPressed: (){
          close(context, null);
        },
        icon: const Icon(Icons.arrow_back)
    );
  }

  List<String> searchTermsName = [
    'Адиантум венерин волос',
    'Адиантум хвостатый',
    'Адиантум стоповидный',
    'Птерис критский',
    'Птерис мечевидный',
    'Блехнум',
    'Нефролепис сердцелистный',
    'Нефролепис мечевидный',
    'Нефролепис возвышенный',
    'Асплениум гнездовой',
    'Асплениум луковиценосный',
    'Асплениум двуформенный',
    'Циртомиум серповидный',
    'Даваллия канарская',
    'Даваллия рассечённая',
  ];

  List<String> searchTermsImage = [
    'https://cdn.botanichka.ru/wp-content/uploads/2009/11/Adiantum-capillus-veneris-3-1-210x210.jpg',
    'https://i.pinimg.com/736x/68/9d/bb/689dbbc3500b965a0e4add738a2990ad.jpg',
    'https://i.pinimg.com/736x/bb/35/b6/bb35b645ad0bb170d46e23ce5471d063.jpg',
    'https://cdn.100sp.ru/pictures/351388381',
    'https://i.etsystatic.com/20406392/r/il/a18300/2509424111/il_794xN.2509424111_fif3.jpg',
    'https://cdn.botanichka.ru/wp-content/uploads/2017/09/Blechnum-03-640x800.jpg',
    'https://cdn.botanichka.ru/wp-content/uploads/2010/04/Nephrolepis_cordifolia_03-640x825.jpg',
    'https://cdn.botanichka.ru/wp-content/uploads/2010/04/Nephrolepis_biserrata_1-640x853.jpg',
    'https://cdn.botanichka.ru/wp-content/uploads/2010/04/Nephrolepis_exaltata_01-640x853.jpg',
    'https://i.pinimg.com/564x/c0/a8/17/c0a8178fe01b66f687df4cfd1e1c8371.jpg',
    'https://bloom-story.ru/wa-data/public/shop/products/04/27/2704/images/6536/6536.750.jpg',
    'https://www.gardentags.com/profile/elicia/images/327842/750/asplenium-dimorphum-x-difforme.jpeg',
    'https://cvetpodokonnik.ru/wa-data/public/shop/products/96/07/796/images/2302/2302.970.jpg',
    'https://klau.club/uploads/posts/2023-03/thumbs/1677622360_klau-club-p-davana-rastenie-krasivo-23.png',
    'https://i5.walmartimages.com/asr/db453a16-9cba-482c-acf7-95d28963df2b_1.a26702021d8199000def5af913252372.jpeg',
  ];

  List<String> searchTermsSubName = [
    'Adiantum capillus-veneris',
    'Adiantum caudatum',
    'Adiantum pedatum',
    'Pteris cretica',
    'Pteris ensiformis',
    'Blechnum spicant',
    'Nephrolepis cordifolia',
    'Nephrolepis biserrata',
    'Nephrolepis exaltata',
    'Asplenium nidus',
    'Asplenium bulbiferum',
    'Asplenium dimorphum',
    'Cyrtomium falcatum',
    'Davallia canariensis',
    'Davallia dissecta',
  ];

  @override
  Widget buildResults(BuildContext context) {
    List<String> matchQueryName = [];
    List<String> matchQueryImage = [];
    List<String> matchQuerySubName = [];
    int i = 0;
    for (var fruit in searchTermsName) {
      if (fruit.toLowerCase().contains(query.toLowerCase())){
        matchQueryName.add(fruit);
        matchQueryImage.add(searchTermsImage[i]);
        matchQuerySubName.add(searchTermsSubName[i]);
      }
      i++;
    }
    int z = 0;
    for (var fruit in searchTermsSubName) {
      if (fruit.toLowerCase().contains(query.toLowerCase())){
        matchQueryName.add(searchTermsName[z]);
        matchQueryImage.add(searchTermsImage[z]);
        matchQuerySubName.add(searchTermsSubName[z]);
      }
      z++;
    }
    return ListView.builder(
        itemCount: matchQueryName.length,
        itemBuilder: (context, index){
          var name = matchQueryName[index];
          var image = matchQueryImage[index];
          var subName = matchQuerySubName[index];
          return elements(ElementName: name, ElementSubName: subName, ElementImage: image);
        }
    );
  }

  @override
  Widget buildSuggestions(BuildContext context) {
    List<String> matchQueryName = [];
    List<String> matchQueryImage = [];
    List<String> matchQuerySubName = [];
    int i = 0;
    for (var fruit in searchTermsName) {
      if (fruit.toLowerCase().contains(query.toLowerCase())){
        matchQueryName.add(fruit);
        matchQueryImage.add(searchTermsImage[i]);
        matchQuerySubName.add(searchTermsSubName[i]);
      }
      i++;
    }
    int z = 0;
    for (var fruit in searchTermsSubName) {
      if (fruit.toLowerCase().contains(query.toLowerCase())){
        matchQueryName.add(searchTermsName[z]);
        matchQueryImage.add(searchTermsImage[z]);
        matchQuerySubName.add(searchTermsSubName[z]);
      }
      z++;
    }
    return ListView.builder(
      itemBuilder: (context, index){
        var name = matchQueryName[index];
        var image = matchQueryImage[index];
        var subName = matchQuerySubName[index];
        return elements(ElementName: name, ElementSubName: subName, ElementImage: image);
      },
      itemCount: query == '' ? matchQueryName.length ~/ 2 : matchQueryName.length,
    );
  }
}