diff --git a/example/ios/Runner.xcodeproj/project.pbxproj b/example/ios/Runner.xcodeproj/project.pbxproj
index 5e16630..fb9bd0e 100644
--- a/example/ios/Runner.xcodeproj/project.pbxproj
+++ b/example/ios/Runner.xcodeproj/project.pbxproj
@@ -9,11 +9,7 @@
 /* Begin PBXBuildFile section */
 		1498D2341E8E89220040F4C2 /* GeneratedPluginRegistrant.m in Sources */ = {isa = PBXBuildFile; fileRef = 1498D2331E8E89220040F4C2 /* GeneratedPluginRegistrant.m */; };
 		3B3967161E833CAA004F5970 /* AppFrameworkInfo.plist in Resources */ = {isa = PBXBuildFile; fileRef = 3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */; };
-		3B80C3941E831B6300D905FE /* App.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 3B80C3931E831B6300D905FE /* App.framework */; };
-		3B80C3951E831B6300D905FE /* App.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 3B80C3931E831B6300D905FE /* App.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
 		74858FAF1ED2DC5600515810 /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 74858FAE1ED2DC5600515810 /* AppDelegate.swift */; };
-		9705A1C61CF904A100538489 /* Flutter.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 9740EEBA1CF902C7004384FC /* Flutter.framework */; };
-		9705A1C71CF904A300538489 /* Flutter.framework in Embed Frameworks */ = {isa = PBXBuildFile; fileRef = 9740EEBA1CF902C7004384FC /* Flutter.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
 		9740EEB41CF90195004384FC /* Debug.xcconfig in Resources */ = {isa = PBXBuildFile; fileRef = 9740EEB21CF90195004384FC /* Debug.xcconfig */; };
 		97C146FC1CF9000F007C117D /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FA1CF9000F007C117D /* Main.storyboard */; };
 		97C146FE1CF9000F007C117D /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 97C146FD1CF9000F007C117D /* Assets.xcassets */; };
@@ -27,8 +23,6 @@
 			dstPath = "";
 			dstSubfolderSpec = 10;
 			files = (
-				3B80C3951E831B6300D905FE /* App.framework in Embed Frameworks */,
-				9705A1C71CF904A300538489 /* Flutter.framework in Embed Frameworks */,
 			);
 			name = "Embed Frameworks";
 			runOnlyForDeploymentPostprocessing = 0;
@@ -39,13 +33,11 @@
 		1498D2321E8E86230040F4C2 /* GeneratedPluginRegistrant.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = GeneratedPluginRegistrant.h; sourceTree = "<group>"; };
 		1498D2331E8E89220040F4C2 /* GeneratedPluginRegistrant.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GeneratedPluginRegistrant.m; sourceTree = "<group>"; };
 		3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; name = AppFrameworkInfo.plist; path = Flutter/AppFrameworkInfo.plist; sourceTree = "<group>"; };
-		3B80C3931E831B6300D905FE /* App.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = App.framework; path = Flutter/App.framework; sourceTree = "<group>"; };
 		74858FAD1ED2DC5600515810 /* Runner-Bridging-Header.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "Runner-Bridging-Header.h"; sourceTree = "<group>"; };
 		74858FAE1ED2DC5600515810 /* AppDelegate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		7AFA3C8E1D35360C0083082E /* Release.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; name = Release.xcconfig; path = Flutter/Release.xcconfig; sourceTree = "<group>"; };
 		9740EEB21CF90195004384FC /* Debug.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; name = Debug.xcconfig; path = Flutter/Debug.xcconfig; sourceTree = "<group>"; };
 		9740EEB31CF90195004384FC /* Generated.xcconfig */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xcconfig; name = Generated.xcconfig; path = Flutter/Generated.xcconfig; sourceTree = "<group>"; };
-		9740EEBA1CF902C7004384FC /* Flutter.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Flutter.framework; path = Flutter/Flutter.framework; sourceTree = "<group>"; };
 		97C146EE1CF9000F007C117D /* Runner.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = Runner.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		97C146FB1CF9000F007C117D /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/Main.storyboard; sourceTree = "<group>"; };
 		97C146FD1CF9000F007C117D /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
@@ -58,8 +50,6 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				9705A1C61CF904A100538489 /* Flutter.framework in Frameworks */,
-				3B80C3941E831B6300D905FE /* App.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -69,9 +59,7 @@
 		9740EEB11CF90186004384FC /* Flutter */ = {
 			isa = PBXGroup;
 			children = (
-				3B80C3931E831B6300D905FE /* App.framework */,
 				3B3967151E833CAA004F5970 /* AppFrameworkInfo.plist */,
-				9740EEBA1CF902C7004384FC /* Flutter.framework */,
 				9740EEB21CF90195004384FC /* Debug.xcconfig */,
 				7AFA3C8E1D35360C0083082E /* Release.xcconfig */,
 				9740EEB31CF90195004384FC /* Generated.xcconfig */,
@@ -203,7 +191,7 @@
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "/bin/sh \"$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh\" thin";
+			shellScript = "/bin/sh \"$FLUTTER_ROOT/packages/flutter_tools/bin/xcode_backend.sh\" embed_and_thin";
 		};
 		9740EEB61CF901F6004384FC /* Run Script */ = {
 			isa = PBXShellScriptBuildPhase;
@@ -255,7 +243,6 @@
 /* Begin XCBuildConfiguration section */
 		249021D3217E4FDB00AE95B9 /* Profile */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_ANALYZER_NONNULL = YES;
@@ -331,7 +318,6 @@
 		};
 		97C147031CF9000F007C117D /* Debug */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_ANALYZER_NONNULL = YES;
@@ -387,7 +373,6 @@
 		};
 		97C147041CF9000F007C117D /* Release */ = {
 			isa = XCBuildConfiguration;
-			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_ANALYZER_NONNULL = YES;
diff --git a/example/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata b/example/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata
index 1d526a1..919434a 100644
--- a/example/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata
+++ b/example/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata
@@ -2,6 +2,6 @@
 <Workspace
    version = "1.0">
    <FileRef
-      location = "group:Runner.xcodeproj">
+      location = "self:">
    </FileRef>
 </Workspace>
diff --git a/example/pubspec.lock b/example/pubspec.lock
index 1849cfc..3a94748 100644
--- a/example/pubspec.lock
+++ b/example/pubspec.lock
@@ -1,62 +1,48 @@
 # Generated by pub
 # See https://dart.dev/tools/pub/glossary#lockfile
 packages:
-  archive:
-    dependency: transitive
-    description:
-      name: archive
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.0.11"
-  args:
-    dependency: transitive
-    description:
-      name: args
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.5.2"
   async:
     dependency: transitive
     description:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.4.0"
+    version: "2.5.0"
   boolean_selector:
     dependency: transitive
     description:
       name: boolean_selector
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.5"
-  charcode:
+    version: "2.1.0"
+  characters:
     dependency: transitive
     description:
-      name: charcode
+      name: characters
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.2"
-  collection:
+    version: "1.1.0"
+  charcode:
     dependency: transitive
     description:
-      name: collection
+      name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.14.11"
-  convert:
+    version: "1.2.0"
+  clock:
     dependency: transitive
     description:
-      name: convert
+      name: clock
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.1"
-  crypto:
+    version: "1.1.0"
+  collection:
     dependency: transitive
     description:
-      name: crypto
+      name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.3"
+    version: "1.15.0"
   cupertino_icons:
     dependency: "direct main"
     description:
@@ -64,13 +50,20 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.1.2"
+  fake_async:
+    dependency: transitive
+    description:
+      name: fake_async
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
   flappy_search_bar:
     dependency: "direct main"
     description:
       path: ".."
       relative: true
     source: path
-    version: "1.6.2"
+    version: "1.8.0"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -82,61 +75,33 @@ packages:
       name: flutter_staggered_grid_view
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.3.0"
+    version: "0.4.0-nullsafety.3"
   flutter_test:
     dependency: "direct dev"
     description: flutter
     source: sdk
     version: "0.0.0"
-  image:
-    dependency: transitive
-    description:
-      name: image
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.1.4"
   matcher:
     dependency: transitive
     description:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.6"
+    version: "0.12.10"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.8"
+    version: "1.3.0"
   path:
     dependency: transitive
     description:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.6.4"
-  pedantic:
-    dependency: transitive
-    description:
-      name: pedantic
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.8.0+1"
-  petitparser:
-    dependency: transitive
-    description:
-      name: petitparser
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.4.0"
-  quiver:
-    dependency: transitive
-    description:
-      name: quiver
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.0.5"
+    version: "1.8.0"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -148,63 +113,56 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.5.5"
+    version: "1.8.0"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.9.3"
+    version: "1.10.0"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.0"
+    version: "2.1.0"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.5"
+    version: "1.1.0"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0"
+    version: "1.2.0"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.11"
+    version: "0.2.19"
   typed_data:
     dependency: transitive
     description:
       name: typed_data
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.6"
+    version: "1.3.0"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.8"
-  xml:
-    dependency: transitive
-    description:
-      name: xml
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "3.5.0"
+    version: "2.1.0"
 sdks:
-  dart: ">=2.4.0 <3.0.0"
-  flutter: ">=1.6.0"
+  dart: ">=2.12.0 <3.0.0"
+  flutter: ">=1.24.0-6.0.pre"
diff --git a/lib/flappy_search_bar.dart b/lib/flappy_search_bar.dart
index 691742f..3a8fc1c 100644
--- a/lib/flappy_search_bar.dart
+++ b/lib/flappy_search_bar.dart
@@ -23,13 +23,13 @@ class SearchBarController<T> {
   final List<T> _list = [];
   final List<T> _filteredList = [];
   final List<T> _sortedList = [];
-  TextEditingController _searchQueryController;
-  String _lastSearchedText;
-  Future<List<T>> Function(String text) _lastSearchFunction;
-  _ControllerListener _controllerListener;
-  int Function(T a, T b) _lastSorting;
-  CancelableOperation _cancelableOperation;
-  int minimumChars;
+  late TextEditingController _searchQueryController;
+  String? _lastSearchedText;
+  Future<List<T>> Function(String? text)? _lastSearchFunction;
+  _ControllerListener? _controllerListener;
+  int Function(T a, T b)? _lastSorting;
+  CancelableOperation<List<T>>? _cancelableOperation;
+  late int minimumChars;
 
   void setTextController(TextEditingController _searchQueryController, minimunChars) {
     this._searchQueryController = _searchQueryController;
@@ -45,20 +45,21 @@ class SearchBarController<T> {
   }
 
   void _search(
-      String text, Future<List<T>> Function(String text) onSearch) async {
+      String? text, Future<List<T>> Function(String? text) onSearch) async {
     _controllerListener?.onLoading();
     try {
       if (_cancelableOperation != null &&
-          (!_cancelableOperation.isCompleted ||
-              !_cancelableOperation.isCanceled)) {
-        _cancelableOperation.cancel();
+          (!_cancelableOperation!.isCompleted ||
+              !_cancelableOperation!.isCanceled)) {
+        _cancelableOperation!.cancel();
       }
       _cancelableOperation = CancelableOperation.fromFuture(
         onSearch(text),
         onCancel: () => {},
       );
 
-      final List<T> items = await _cancelableOperation.value;
+
+      final List<T> items = await (_cancelableOperation!.value);
       _lastSearchFunction = onSearch;
       _lastSearchedText = text;
       _list.clear();
@@ -68,13 +69,13 @@ class SearchBarController<T> {
       _list.addAll(items);
       _controllerListener?.onListChanged(_list);
     } catch (error) {
-      _controllerListener?.onError(error);
+      _controllerListener?.onError(error as Error);
     }
   }
 
   void injectSearch(
-      String searchText, Future<List<T>> Function(String text) onSearch) {
-    if (searchText != null && searchText.length >= minimumChars) {
+      String searchText, Future<List<T>> Function(String? text) onSearch) {
+    if (searchText.length >= minimumChars) {
       _searchQueryController.text = searchText;
       _search(searchText, onSearch);
     }
@@ -82,7 +83,7 @@ class SearchBarController<T> {
 
   void replayLastSearch() {
     if (_lastSearchFunction != null && _lastSearchedText != null) {
-      _search(_lastSearchedText, _lastSearchFunction);
+      _search(_lastSearchedText, _lastSearchFunction!);
     }
   }
 
@@ -128,13 +129,13 @@ typedef ScaledTile IndexedScaledTileBuilder(int index);
 
 class SearchBar<T> extends StatefulWidget {
   /// Future returning searched items
-  final Future<List<T>> Function(String text) onSearch;
+  final Future<List<T>> Function(String? text) onSearch;
 
   /// List of items showed by default
   final List<T> suggestions;
 
   /// Callback returning the widget corresponding to a Suggestion item
-  final Widget Function(T item, int index) buildSuggestion;
+  final Widget Function(T item, int index)? buildSuggestion;
 
   /// Minimum number of chars required for a search
   final int minimumChars;
@@ -143,7 +144,7 @@ class SearchBar<T> extends StatefulWidget {
   final Widget Function(T item, int index) onItemFound;
 
   /// Callback returning the widget corresponding to an Error while searching
-  final Widget Function(Error error) onError;
+  final Widget Function(Error error)? onError;
 
   /// Cooldown between each call to avoid too many
   final Duration debounceDuration;
@@ -155,13 +156,13 @@ class SearchBar<T> extends StatefulWidget {
   final Widget emptyWidget;
 
   /// Widget to show by default
-  final Widget placeHolder;
+  final Widget? placeHolder;
 
   /// Widget showed on left of the search bar
   final Widget icon;
 
   /// Widget placed between the search bar and the results
-  final Widget header;
+  final Widget? header;
 
   /// Hint text of the search bar
   final String hintText;
@@ -179,10 +180,10 @@ class SearchBar<T> extends StatefulWidget {
   final Widget cancellationWidget;
 
   /// Callback when cancel button is triggered
-  final VoidCallback onCancelled;
+  final VoidCallback? onCancelled;
 
   /// Controller used to be able to sort, filter or replay the search
-  final SearchBarController searchBarController;
+  final SearchBarController? searchBarController;
 
   /// Enable to edit the style of the search bar
   final SearchBarStyle searchBarStyle;
@@ -195,7 +196,7 @@ class SearchBar<T> extends StatefulWidget {
 
   /// Called to get the tile at the specified index for the
   /// [SliverGridStaggeredTileLayout].
-  final IndexedScaledTileBuilder indexedScaledTileBuilder;
+  final IndexedScaledTileBuilder? indexedScaledTileBuilder;
 
   /// Set the scrollDirection
   final Axis scrollDirection;
@@ -216,9 +217,9 @@ class SearchBar<T> extends StatefulWidget {
   final EdgeInsetsGeometry listPadding;
 
   SearchBar({
-    Key key,
-    @required this.onSearch,
-    @required this.onItemFound,
+    Key? key,
+    required this.onSearch,
+    required this.onItemFound,
     this.searchBarController,
     this.minimumChars = 3,
     this.debounceDuration = const Duration(milliseconds: 500),
@@ -252,15 +253,15 @@ class SearchBar<T> extends StatefulWidget {
   _SearchBarState createState() => _SearchBarState<T>();
 }
 
-class _SearchBarState<T> extends State<SearchBar<T>>
-    with TickerProviderStateMixin, _ControllerListener<T> {
+class _SearchBarState<T> extends State<SearchBar<T?>>
+    with TickerProviderStateMixin, _ControllerListener<T?> {
   bool _loading = false;
-  Widget _error;
+  Widget? _error;
   final _searchQueryController = TextEditingController();
-  Timer _debounce;
+  Timer? _debounce;
   bool _animate = false;
-  List<T> _list = [];
-  SearchBarController searchBarController;
+  List<T?> _list = [];
+  late SearchBarController searchBarController;
 
   @override
   void initState() {
@@ -272,7 +273,7 @@ class _SearchBarState<T> extends State<SearchBar<T>>
   }
 
   @override
-  void onListChanged(List<T> items) {
+  void onListChanged(List<T?> items) {
     setState(() {
       _loading = false;
       _list = items;
@@ -297,17 +298,17 @@ class _SearchBarState<T> extends State<SearchBar<T>>
   void onError(Error error) {
     setState(() {
       _loading = false;
-      _error = widget.onError != null ? widget.onError(error) : Text("error");
+      _error = widget.onError != null ? widget.onError!(error) : Text("error");
     });
   }
 
   _onTextChanged(String newText) async {
     if (_debounce?.isActive ?? false) {
-      _debounce.cancel();
+      _debounce!.cancel();
     }
 
     _debounce = Timer(widget.debounceDuration, () async {
-      if (newText.length >= widget.minimumChars && widget.onSearch != null) {
+      if (newText.length >= widget.minimumChars) {
         searchBarController._search(newText, widget.onSearch);
       } else {
         setState(() {
@@ -322,7 +323,7 @@ class _SearchBarState<T> extends State<SearchBar<T>>
 
   void _cancel() {
     if (widget.onCancelled != null) {
-      widget.onCancelled();
+      widget.onCancelled!();
     }
 
     setState(() {
@@ -335,7 +336,7 @@ class _SearchBarState<T> extends State<SearchBar<T>>
   }
 
   Widget _buildListView(
-      List<T> items, Widget Function(T item, int index) builder) {
+      List<T?> items, Widget Function(T? item, int index) builder) {
     return Padding(
       padding: widget.listPadding,
       child: StaggeredGridView.countBuilder(
@@ -343,7 +344,7 @@ class _SearchBarState<T> extends State<SearchBar<T>>
         itemCount: items.length,
         shrinkWrap: widget.shrinkWrap,
         staggeredTileBuilder:
-            widget.indexedScaledTileBuilder ?? (int index) => ScaledTile.fit(1),
+            widget.indexedScaledTileBuilder ?? ((int index) => ScaledTile.fit(1)),
         scrollDirection: widget.scrollDirection,
         mainAxisSpacing: widget.mainAxisSpacing,
         crossAxisSpacing: widget.crossAxisSpacing,
@@ -355,7 +356,7 @@ class _SearchBarState<T> extends State<SearchBar<T>>
     );
   }
 
-  Widget _buildContent(BuildContext context) {
+  Widget? _buildContent(BuildContext context) {
     if (_error != null) {
       return _error;
     } else if (_loading) {
@@ -441,7 +442,7 @@ class _SearchBarState<T> extends State<SearchBar<T>>
           child: widget.header ?? Container(),
         ),
         Expanded(
-          child: _buildContent(context),
+          child: _buildContent(context)!,
         ),
       ],
     );
diff --git a/lib/scaled_tile.dart b/lib/scaled_tile.dart
index 10e156b..2929254 100644
--- a/lib/scaled_tile.dart
+++ b/lib/scaled_tile.dart
@@ -26,6 +26,6 @@ class ScaledTile extends StaggeredTile {
   /// [mainAxisCellCount] cells (inner spacings included).
   ScaledTile.count(
     int crossAxisCellCount,
-    num mainAxisCellCount,
+    double mainAxisCellCount,
   ) : super.count(crossAxisCellCount, mainAxisCellCount);
 }
diff --git a/pubspec.lock b/pubspec.lock
index 9a50fcf..7af8cf8 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -1,62 +1,55 @@
 # Generated by pub
 # See https://dart.dev/tools/pub/glossary#lockfile
 packages:
-  archive:
-    dependency: transitive
-    description:
-      name: archive
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.0.11"
-  args:
-    dependency: transitive
-    description:
-      name: args
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.5.2"
   async:
     dependency: "direct main"
     description:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.4.0"
+    version: "2.5.0"
   boolean_selector:
     dependency: transitive
     description:
       name: boolean_selector
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.5"
+    version: "2.1.0"
+  characters:
+    dependency: transitive
+    description:
+      name: characters
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0"
   charcode:
     dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.2"
-  collection:
+    version: "1.2.0"
+  clock:
     dependency: transitive
     description:
-      name: collection
+      name: clock
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.14.11"
-  convert:
+    version: "1.1.0"
+  collection:
     dependency: transitive
     description:
-      name: convert
+      name: collection
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.1"
-  crypto:
+    version: "1.15.0"
+  fake_async:
     dependency: transitive
     description:
-      name: crypto
+      name: fake_async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.1.3"
+    version: "1.2.0"
   flutter:
     dependency: "direct main"
     description: flutter
@@ -68,61 +61,33 @@ packages:
       name: flutter_staggered_grid_view
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.3.0"
+    version: "0.4.0-nullsafety.3"
   flutter_test:
     dependency: "direct dev"
     description: flutter
     source: sdk
     version: "0.0.0"
-  image:
-    dependency: transitive
-    description:
-      name: image
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.1.4"
   matcher:
     dependency: transitive
     description:
       name: matcher
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.6"
+    version: "0.12.10"
   meta:
     dependency: transitive
     description:
       name: meta
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.8"
+    version: "1.3.0"
   path:
     dependency: transitive
     description:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.6.4"
-  pedantic:
-    dependency: transitive
-    description:
-      name: pedantic
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "1.8.0+1"
-  petitparser:
-    dependency: transitive
-    description:
-      name: petitparser
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.4.0"
-  quiver:
-    dependency: transitive
-    description:
-      name: quiver
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "2.0.5"
+    version: "1.8.0"
   sky_engine:
     dependency: transitive
     description: flutter
@@ -134,63 +99,56 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.5.5"
+    version: "1.8.0"
   stack_trace:
     dependency: transitive
     description:
       name: stack_trace
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.9.3"
+    version: "1.10.0"
   stream_channel:
     dependency: transitive
     description:
       name: stream_channel
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.0"
+    version: "2.1.0"
   string_scanner:
     dependency: transitive
     description:
       name: string_scanner
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.0.5"
+    version: "1.1.0"
   term_glyph:
     dependency: transitive
     description:
       name: term_glyph
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.0"
+    version: "1.2.0"
   test_api:
     dependency: transitive
     description:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.11"
+    version: "0.2.19"
   typed_data:
     dependency: transitive
     description:
       name: typed_data
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.1.6"
+    version: "1.3.0"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.0.8"
-  xml:
-    dependency: transitive
-    description:
-      name: xml
-      url: "https://pub.dartlang.org"
-    source: hosted
-    version: "3.5.0"
+    version: "2.1.0"
 sdks:
-  dart: ">=2.4.0 <3.0.0"
-  flutter: ">=1.6.0"
+  dart: ">=2.12.0 <3.0.0"
+  flutter: ">=1.24.0-6.0.pre"
diff --git a/pubspec.yaml b/pubspec.yaml
index 8cc66dc..36d08aa 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,16 +1,16 @@
 name: flappy_search_bar
 description: A SearchBar widget automatizing most of your asynchronous searchs cases.
-version: 1.7.2
+version: 1.8.0
 homepage: https://github.com/smartnsoft/flappy_search_bar
 
 environment:
-  sdk: ">=2.1.0 <3.0.0"
+  sdk: '>=2.12.0 <3.0.0'
 
 dependencies:
   flutter:
     sdk: flutter
-  async: ^2.2.0
-  flutter_staggered_grid_view: ^0.3.0
+  async: ^2.5.0
+  flutter_staggered_grid_view: ^0.4.0-nullsafety.3
 
 dev_dependencies:
   flutter_test: