How to use pagination in flutter using FutureBuilder with ListView? - flutter

Question

I'm new as a Flutter programmer and I'm having difficulty working with a list that has pagination, if I remove the pagination the list doesn't load. Need help. The state manager I'm using is Getx.
This is my DTO class.
class PaginationFilter {
int? page;
int? pagesize;
#override
String toString() {
return 'PaginationFilterAlbum{page: $page, pagesize: $pagesize}';
}
#override
bool operator ==(Object other) =>
identical(this, other) ||
other is PaginationFilter &&
runtimeType == other.runtimeType &&
page == other.page &&
pagesize == other.pagesize;
#override
int get hashCode => page.hashCode ^ pagesize.hashCode;
}
Here is where I consume the API.
Future<List<Post>> getAlbum(PaginationFilter filter, {
bool isFavoritedPage = false,
bool isNewEdition = false,
}) async {
dio.options.headers['Cookie'] = 'ASP.NET_SessionId=${user.sessionID}';
final response = await dio.get(
isFavoritedPage ? AppConstants.apiFavoritedsPost : AppConstants.apiPosts,
queryParameters: {
'sessionId': user.sessionID,
'CodUserProfile': '${user.codUser!}',
'CodUserLogged': '${user.codUser!}',
'Page': '${filter.page}', /*Aqui fica a pagina*/
'pagesize': '${filter.pagesize}', /*Aqui a quantidade de registros em cada pagina*/
'myPostOnly': isFavoritedPage ? 'true' : 'false',
},
);
final body = response.data['ListPosts'] as List;
return body.map((post) => Post.fromJson(post)).toList();
}
Here is my controller class
final _posts = <Post>[].obs;
var response = null;
final _paginationFilterAlbum = PaginationFilter().obs;
int? get pagesize => _paginationFilterAlbum.value.pagesize;
int? get _page => _paginationFilterAlbum.value.page;
final _lastPageAlgum = false.obs;
bool get lastPageAlgum => _lastPageAlgum.value;
#override
void onInit(){
ever(_paginationFilterAlbum, (_) => getAlbum());
_changePaginationFilterAlgum(1, 10);
super.onInit();
}
void _changePaginationFilterAlgum(int page, int pagesize){
_paginationFilterAlbum.update((val) {
val?.page = page;
val?.pagesize = pagesize;
});
}
void changeTotalPerPage(int limitValue){
_posts.clear();
_lastPageAlgum.value = false;
_changePaginationFilterAlgum(1, limitValue);
}
void nextPage() => _changePaginationFilterAlgum(_page! + 1, pagesize!);
Future<List<Post>> getAlbum([bool isFavoritedPage = false]) async {
response =
await repository.getAlbum(_paginationFilterAlbum.value,isFavoritedPage: isFavoritedPage);
if(response.isEmpty){
_lastPageAlgum. value = true;
}
_posts.addAll(response);
return response;
}
here is my my list
Expanded(
child: FutureBuilder<List<Post>>(
future: controller.getAlbum(),
builder: (context, snapshot) {
final List<Post> posts = snapshot.data ?? [];
if (snapshot.connectionState == ConnectionState.waiting) {
return const Center(child: CupertinoActivityIndicator());
}
return ListView.builder(
physics: const BouncingScrollPhysics(),
itemCount: posts.length,
itemBuilder: (context, index) {
return PostWidget(post: posts[index]);
},
);
},
),
),
Could you please help me how do I load the entire list using pagination?