Refactor part list

lib/widget/part_list.dart

@@ -0,0 +1,201 @@
+import 'package:flutter/material.dart';
+import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
+import 'package:inventree/inventree/part.dart';
+import 'package:inventree/inventree/sentry.dart';
+import 'package:inventree/widget/paginator.dart';
+import 'package:inventree/widget/part_detail.dart';
+import 'package:inventree/widget/refreshable_state.dart';
+
+import '../api.dart';
+import '../app_settings.dart';
+import '../l10.dart';
+
+
+class PartList extends StatefulWidget {
+
+  const PartList(this.filters);
+
+  final Map<String, String> filters;
+
+  @override
+  _PartListState createState() => _PartListState(filters);
+}
+
+
+class _PartListState extends RefreshableState<PartList> {
+
+  _PartListState(this.filters);
+
+  final Map<String, String> filters;
+
+  @override
+  String getAppBarTitle(BuildContext context) => L10().parts;
+
+  @override
+  Widget getBody(BuildContext context) {
+    return PaginatedPartList(filters);
+  }
+
+}
+
+
+class PaginatedPartList extends StatefulWidget {
+
+  const PaginatedPartList(this.filters, {this.onTotalChanged});
+
+  final Map<String, String> filters;
+
+  final Function(int)? onTotalChanged;
+
+  @override
+  _PaginatedPartListState createState() => _PaginatedPartListState(filters, onTotalChanged);
+}
+
+
+class _PaginatedPartListState extends State<PaginatedPartList> {
+
+  _PaginatedPartListState(this.filters, this.onTotalChanged);
+
+  static const _pageSize = 25;
+
+  String _searchTerm = "";
+
+  Function(int)? onTotalChanged;
+
+  final Map<String, String> filters;
+
+  final PagingController<int, InvenTreePart> _pagingController = PagingController(firstPageKey: 0);
+
+  @override
+  void initState() {
+    _pagingController.addPageRequestListener((pageKey) {
+      _fetchPage(pageKey);
+    });
+
+    super.initState();
+  }
+
+  @override
+  void dispose() {
+    _pagingController.dispose();
+    super.dispose();
+  }
+
+  int resultCount = 0;
+
+  Future<void> _fetchPage(int pageKey) async {
+    try {
+
+      Map<String, String> params = filters;
+
+      params["search"] = _searchTerm;
+
+      final bool cascade = await InvenTreeSettingsManager().getBool("partSubcategory", true);
+
+      params["cascade"] = "${cascade}";
+
+      final page = await InvenTreePart().listPaginated(_pageSize, pageKey, filters: params);
+      int pageLength = page?.length ?? 0;
+      int pageCount = page?.count ?? 0;
+
+      final isLastPage = pageLength < _pageSize;
+
+      // Construct a list of part objects
+      List<InvenTreePart> parts = [];
+
+      if (page != null) {
+        for (var result in page.results) {
+          if (result is InvenTreePart) {
+            parts.add(result);
+          }
+        }
+      }
+
+      if (isLastPage) {
+        _pagingController.appendLastPage(parts);
+      } else {
+        final int nextPageKey = pageKey + pageLength;
+        _pagingController.appendPage(parts, nextPageKey);
+      }
+
+      if (onTotalChanged != null) {
+        onTotalChanged!(pageCount);
+      }
+
+      setState(() {
+        resultCount = pageCount;
+      });
+
+    } catch (error, stackTrace) {
+      print("Error! - ${error.toString()}");
+      _pagingController.error = error;
+
+      sentryReportError(error, stackTrace);
+    }
+  }
+
+  void _openPart(BuildContext context, int pk) {
+    // Attempt to load the part information
+    InvenTreePart().get(pk).then((var part) {
+      if (part is InvenTreePart) {
+
+        Navigator.push(context, MaterialPageRoute(builder: (context) => PartDetailWidget(part)));
+      }
+    });
+  }
+
+  Widget _buildPart(BuildContext context, InvenTreePart part) {
+    return ListTile(
+      title: Text(part.fullname),
+      subtitle: Text("${part.description}"),
+      trailing: Text("${part.inStockString}"),
+      leading: InvenTreeAPI().getImage(
+        part.thumbnail,
+        width: 40,
+        height: 40,
+      ),
+      onTap: () {
+        _openPart(context, part.pk);
+      },
+    );
+  }
+
+  final TextEditingController searchController = TextEditingController();
+
+  void updateSearchTerm() {
+
+    _searchTerm = searchController.text;
+    _pagingController.refresh();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Column(
+      mainAxisAlignment: MainAxisAlignment.start,
+      children: [
+        PaginatedSearchWidget(searchController, updateSearchTerm, resultCount),
+        Expanded(
+            child: CustomScrollView(
+              shrinkWrap: true,
+              physics: ClampingScrollPhysics(),
+              scrollDirection: Axis.vertical,
+              slivers: [
+                PagedSliverList.separated(
+                  pagingController: _pagingController,
+                  builderDelegate: PagedChildBuilderDelegate<InvenTreePart>(
+                    itemBuilder: (context, item, index) {
+                      return _buildPart(context, item);
+                    },
+                    noItemsFoundIndicatorBuilder: (context) {
+                      return NoResultsWidget(L10().partNoResults);
+                    },
+                  ),
+                  separatorBuilder: (context, index) => const Divider(height: 1),
+                )
+              ],
+            )
+        )
+      ],
+    );
+  }
+}