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How to avoid using FutureBuilder as it is duplicating items in setState

Time:09-20

I believe I am having issues with using setState in a futurebuilder - but Im not sure how to change this? Below you can see I am building a listView using a futureBuilder (http request to api) and connecting it to my ProjectModel model. From here I filter the values I need into List<ProjectSearch> searchList. What I am finding is when I try to implement a search box to filter through the objects I believe the setState is causing the futurebuilder to rebuild the page each time causing duplications. How can I separate the futurebuilder from the listView so that it only displays the one list object as the user types?

        class _HomePageState extends State<HomePage> {
          TextEditingController controller = TextEditingController();
           late final Future<ProjectModel> futureProjects;

            List<ProjectSearch> searchList = [];
            List<ProjectSearch> finder = [];
            var jobNames = [];
            var jobNumbers = [];
            var techs = [];
            var pms = [];
            var address = [];
            var majors = [];
            var budget = [];

          @override
          void initState() {
          super.initState();
         futureProjects = fetchProjects();
         }

         @override
         Widget build(BuildContext context) {
          return Scaffold(
            appBar: AppBar(
            title: const Text(
                 'Upcoming/Live Projects',
             style: TextStyle(
                 color: Colors.white,
                fontSize: 18,
                 fontWeight: FontWeight.bold,
                 ),
               ),
              backgroundColor: ColorConstants.darkScaffoldBackgroundColor,
             ),
           drawer: const CustomDrawer(),
            backgroundColor: ColorConstants.lightScaffoldBackgroundColor,

  
        body: Center(
        child: FutureBuilder<ProjectModel>(
            future: futureProjects,
            builder: (context, snapshot) {
              // finder.clear();
              if (snapshot.hasData) {
                var data = snapshot.data!;
                var columns = data.columns;
                var rows = data.rows;

                for (var item in rows!) {
                  var cells = item.cells;
                  for (var elements in cells!) {
                    if (elements.columnId != null) {
                      if (elements.columnId == 2057691532158852) {
                        var displayValues = elements.displayValue;
                        if (displayValues != null) {
                          jobNames.add(displayValues);
                        }
                        if (displayValues == null) {
                          pms.removeLast();
                          techs.removeLast();
                          address.removeLast();
                          majors.removeLast();
                          budget.removeLast();
                        }
                      }
                      if (elements.columnId == 697505454286724) {
                        var projectNumber = elements.displayValue;
                        if (projectNumber != null) {
                          jobNumbers.add(projectNumber);
                        }
                      }
                      if (elements.columnId == 7452904895342468) {
                        var techAssigned = elements.displayValue;
                        if (techAssigned != null) {
                          if (techAssigned == '[email protected]') {
                            techAssigned = 'Ts';
                            techs.add(techAssigned);
                          } else {
                            techs.add(techAssigned);
                          }
                        }
                        if (techAssigned == null) {
                          techAssigned = 'No tech assigned as yet';
                          techs.add(techAssigned);
                        }
                      }
                      if (elements.columnId == 2949305267971972) {
                        var pmName = elements.displayValue;
                        if (pmName != null) {
                          pms.add(pmName);
                        }
                        if (pmName == null) {
                          pmName = 'No project manager allocated';
                          pms.add(pmName);
                        }
                      }
                      if (elements.columnId == 5201105081657220) {
                        var addressValue = elements.displayValue;
                        if (addressValue != null) {
                          address.add(addressValue);
                        }
                        if (addressValue == null) {
                          addressValue = '';
                          address.add(addressValue);
                        }
                      }
                      if (elements.columnId == 52961559766916) {
                        var majorValue = elements.displayValue;
                        if (majorValue != null) {
                          majors.add(majorValue);
                        }
                        if (majorValue == null) {
                          majorValue = 'No';
                          majors.add(majorValue);
                        }
                      }
                      if (elements.columnId == 4226807856686980) {
                        var budgetHours = elements.displayValue;
                        if (budgetHours != null) {
                          budget.add(budgetHours);
                        }
                        if (budgetHours == null) {
                          budgetHours = 'TBA';
                          budget.add(budgetHours);
                        }
                      }
                    }
                  }
                }

                int index = 0;
                for (int i = 0; i < jobNames.length; i  ) {
                  // List<ProjectSearch> innerMap = [];
                  ProjectSearch myProjects = ProjectSearch(
                      address: jobNames[index],
                      budget: budget[index],
                      jobNumber: jobNumbers[index],
                      major: majors[index],
                      name: jobNames[index],
                      pM: pms[index],
                      tech: techs[index]);

                  index  ;

                  searchList.add(myProjects);
                }
                return Container(
                  child: Column(
                    children: <Widget>[
                      Padding(
                        padding:
                            const EdgeInsets.only(left: 20, top: 20, right: 20),
                        child: TextField(
                          textAlign: TextAlign.center,
                          controller: controller,
                          onChanged: search,
                          keyboardType: const TextInputType.numberWithOptions(
                              signed: true),
                          // keeps going....
                      ),
                      Expanded(
                        child: ListView.builder(
                            shrinkWrap: true,
                            itemCount: finder.length,
                            itemBuilder: (context, index) {
                              // print(finder.length);
                              final projectData = finder[index];
                              return MaterialButton(
                                onPressed: () => showModalBottomSheet<void>(
                                  backgroundColor: Colors.transparent,
                                  context: context,
                                  builder: (BuildContext context) {
                                    return ClipRRect(
                                      borderRadius: const BorderRadius.only(
                                          topRight: Radius.circular(27.0),
                                          topLeft: Radius.circular(27.0)),
                                      child: Container(
                                        height: 1000,
                                        color: ColorConstants
                                            .secondaryDarkAppColor,
                                        child: Column(
                                          mainAxisSize: MainAxisSize.min,
                                          children: <Widget>[
                                            Flexible(
                                              child: Container(
                                                height: 400,
                                                margin: const EdgeInsets.only(
                                                    top: 20,
                                                    left: 20,
                                                    right: 20),
                                                child: Column(
                                                  crossAxisAlignment:
                                                      CrossAxisAlignment.start,
                                                  mainAxisAlignment:
                                                      MainAxisAlignment
                                                          .spaceAround,
                                                  children: [
                                                    const Padding(
                                                        padding:
                                                            EdgeInsets.only(
                                                                top: 10.0,
                                                                bottom: 5.0)),
                                                    const Center(
                                                      child: Text(
                                                        'Project Details',
                                                        style: TextStyle(
                                                            color: Colors.white,
                                                            fontSize: 20,
                                                            fontWeight:
                                                                FontWeight
                                                                    .w700),
                                                      ),
                                                    ),
                                                    Row(

                                                      children: [
                                                        const Text(
                                                          'Project: ',
                                                          style: TextStyle(
                                                              color: Colors
                                                                  .white70,
                                                              fontWeight:
                                                                  FontWeight
                                                                      .w600,
                                                              fontSize: 17),
                                                        ),
                                                        const SizedBox(
                                                            width: 20),
                                                        Flexible(
                                                          child: Padding(
                                                            padding:
                                                                const EdgeInsets
                                                                        .symmetric(
                                                                    horizontal:
                                                                        8.0),
                                                            child: Text(
                                                              projectData.name,
                                                              overflow:
                                                                  TextOverflow
                                                                      .ellipsis,
                                                              maxLines: 2,
                                                              style: const TextStyle(
                                                                  color: Colors
                                                                      .white,
                                                                  fontWeight:
                                                                      FontWeight
                                                                          .w600,
                                                                  fontSize: 17),
                                                            ),
                                                          ),
                                                        ),
                                                      ],
                                                    ),                                     
                                          ],
                                        ),
                                      ),
                                    );
                                  },
                                ),
                                child: Container(
                                  height: 50,
                                  margin: const EdgeInsets.only(
                                      top: 30, left: 20, right: 20),
                                  decoration: const BoxDecoration(
                                    color: ColorConstants
                                        .darkScaffoldBackgroundColor,
                                    borderRadius:
                                        BorderRadius.all(Radius.circular(8)),
                                  ),
                                  padding: const EdgeInsets.all(15),
                                  child: Center(
                                    child: Text(
                                      projectData.name,
                                      textAlign: TextAlign.center,
                                      style: const TextStyle(
                                          color: Colors.white,
                                          fontWeight: FontWeight.w600,
                                          fontSize: 17),
                                    ),
                                  ),
                                ),
                              );
                            }),
                      ),
                    ],
                  ),
                );
              } else if (snapshot.hasError) {
                print(snapshot);
                return Text(
                  '${snapshot.error}',
                  style: const TextStyle(color: Colors.white),
                );
              } else {
                return const CircularProgressIndicator();
              }
            }),
           ),
          );
          }

        void search(String query) {
   
          final suggestions = searchList.where((search) {
          final projectName = search.name.toLowerCase();
          final input = query.toLowerCase();
           return projectName.contains(input);
           }).toList();

           setState(() {
            finder.clear();
            finder = suggestions;
           });
          } 
          }

Here is what my UI looks like after searching.... UI

CodePudding user response:

Inside your FutureBuilder's builder, try this:

searchList = [];// <---- add this
int index = 0;
for (int i = 0; i < jobNames.length; i  ) {
   // List<ProjectSearch> innerMap = [];
   ProjectSearch myProjects = ProjectSearch(
   address: jobNames[index],
   budget: budget[index],
   jobNumber: jobNumbers[index],
   major: majors[index],
   name: jobNames[index],
   pM: pms[index],
   tech: techs[index]);

   index  ;

   searchList.add(myProjects);
 }

CodePudding user response:

define the future in the build and use it once like this:

..
 Widget build(BuildContext context) {
  Future<ProjectModel> futureProjects = fetchProjects() ;
...

Then remove it in the initState() and use it in the future builder like you've done. Refer to this and read more on when to use initSate() and when to use FutureBuilder()

About your Query search: Try removing the setState() in the search method

void search(String query) {
  
         final suggestions = searchList.where((search) {
         final projectName = search.name.toLowerCase();
         final input = query.toLowerCase();
          return projectName.contains(input);
          }).toList();


         } 
         }
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