[image_picker] Migrate to null-safety (#3524)

Migrate image_picker to null-safety

Author: Sameerkash

packages/image_picker/image_picker/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 0.7.0-nullsafety
+* Migrate to nullsafety
+* Breaking Changes:
+    * Removed the deprecated methods: `ImagePicker.pickImage`, `ImagePicker.pickVideo`,
+`ImagePicker.retrieveLostData`
+
 ## 0.6.7+22
 
 * iOS: update XCUITests to separate each test session.

packages/image_picker/image_picker/example/lib/main.dart

@@ -29,60 +29,63 @@ class MyApp extends StatelessWidget {
 }
 
 class MyHomePage extends StatefulWidget {
-  MyHomePage({Key key, this.title}) : super(key: key);
+  MyHomePage({Key? key, this.title}) : super(key: key);
 
-  final String title;
+  final String? title;
 
   @override
   _MyHomePageState createState() => _MyHomePageState();
 }
 
 class _MyHomePageState extends State<MyHomePage> {
-  PickedFile _imageFile;
+  PickedFile? _imageFile;
   dynamic _pickImageError;
   bool isVideo = false;
-  VideoPlayerController _controller;
-  VideoPlayerController _toBeDisposed;
-  String _retrieveDataError;
+  VideoPlayerController? _controller;
+  VideoPlayerController? _toBeDisposed;
+  String? _retrieveDataError;
 
   final ImagePicker _picker = ImagePicker();
   final TextEditingController maxWidthController = TextEditingController();
   final TextEditingController maxHeightController = TextEditingController();
   final TextEditingController qualityController = TextEditingController();
 
-  Future<void> _playVideo(PickedFile file) async {
+  Future<void> _playVideo(PickedFile? file) async {
     if (file != null && mounted) {
       await _disposeVideoController();
+      late VideoPlayerController controller;
       if (kIsWeb) {
-        _controller = VideoPlayerController.network(file.path);
-        // In web, most browsers won't honor a programmatic call to .play
-        // if the video has a sound track (and is not muted).
-        // Mute the video so it auto-plays in web!
-        // This is not needed if the call to .play is the result of user
-        // interaction (clicking on a "play" button, for example).
-        await _controller.setVolume(0.0);
+        controller = VideoPlayerController.network(file.path);
       } else {
-        _controller = VideoPlayerController.file(File(file.path));
-        await _controller.setVolume(1.0);
+        controller = VideoPlayerController.file(File(file.path));
       }
-      await _controller.initialize();
-      await _controller.setLooping(true);
-      await _controller.play();
+      _controller = controller;
+      // In web, most browsers won't honor a programmatic call to .play
+      // if the video has a sound track (and is not muted).
+      // Mute the video so it auto-plays in web!
+      // This is not needed if the call to .play is the result of user
+      // interaction (clicking on a "play" button, for example).
+      final double volume = kIsWeb ? 0.0 : 1.0;
+      await controller.setVolume(volume);
+      await controller.initialize();
+      await controller.setLooping(true);
+      await controller.play();
       setState(() {});
     }
   }
 
-  void _onImageButtonPressed(ImageSource source, {BuildContext context}) async {
+  void _onImageButtonPressed(ImageSource source,
+      {BuildContext? context}) async {
     if (_controller != null) {
-      await _controller.setVolume(0.0);
+      await _controller!.setVolume(0.0);
     }
     if (isVideo) {
-      final PickedFile file = await _picker.getVideo(
+      final PickedFile? file = await _picker.getVideo(
           source: source, maxDuration: const Duration(seconds: 10));
       await _playVideo(file);
     } else {
-      await _displayPickImageDialog(context,
-          (double maxWidth, double maxHeight, int quality) async {
+      await _displayPickImageDialog(context!,
+          (double? maxWidth, double? maxHeight, int? quality) async {
         try {
           final pickedFile = await _picker.getImage(
             source: source,
@@ -105,8 +108,8 @@ class _MyHomePageState extends State<MyHomePage> {
   @override
   void deactivate() {
     if (_controller != null) {
-      _controller.setVolume(0.0);
-      _controller.pause();
+      _controller!.setVolume(0.0);
+      _controller!.pause();
     }
     super.deactivate();
   }
@@ -122,14 +125,14 @@ class _MyHomePageState extends State<MyHomePage> {
 
   Future<void> _disposeVideoController() async {
     if (_toBeDisposed != null) {
-      await _toBeDisposed.dispose();
+      await _toBeDisposed!.dispose();
     }
     _toBeDisposed = _controller;
     _controller = null;
   }
 
   Widget _previewVideo() {
-    final Text retrieveError = _getRetrieveErrorWidget();
+    final Text? retrieveError = _getRetrieveErrorWidget();
     if (retrieveError != null) {
       return retrieveError;
     }
@@ -146,18 +149,18 @@ class _MyHomePageState extends State<MyHomePage> {
   }
 
   Widget _previewImage() {
-    final Text retrieveError = _getRetrieveErrorWidget();
+    final Text? retrieveError = _getRetrieveErrorWidget();
     if (retrieveError != null) {
       return retrieveError;
     }
     if (_imageFile != null) {
       if (kIsWeb) {
         // Why network?
         // See https://pub.dev/packages/image_picker#getting-ready-for-the-web-platform
-        return Image.network(_imageFile.path);
+        return Image.network(_imageFile!.path);
       } else {
         return Semantics(
-            child: Image.file(File(_imageFile.path)),
+            child: Image.file(File(_imageFile!.path)),
             label: 'image_picker_example_picked_image');
       }
     } else if (_pickImageError != null) {
@@ -189,15 +192,15 @@ class _MyHomePageState extends State<MyHomePage> {
         });
       }
     } else {
-      _retrieveDataError = response.exception.code;
+      _retrieveDataError = response.exception!.code;
     }
   }
 
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
-        title: Text(widget.title),
+        title: Text(widget.title!),
       ),
       body: Center(
         child: !kIsWeb && defaultTargetPlatform == TargetPlatform.android
@@ -288,9 +291,9 @@ class _MyHomePageState extends State<MyHomePage> {
     );
   }
 
-  Text _getRetrieveErrorWidget() {
+  Text? _getRetrieveErrorWidget() {
     if (_retrieveDataError != null) {
-      final Text result = Text(_retrieveDataError);
+      final Text result = Text(_retrieveDataError!);
       _retrieveDataError = null;
       return result;
     }
@@ -336,13 +339,13 @@ class _MyHomePageState extends State<MyHomePage> {
               TextButton(
                   child: const Text('PICK'),
                   onPressed: () {
-                    double width = maxWidthController.text.isNotEmpty
+                    double? width = maxWidthController.text.isNotEmpty
                         ? double.parse(maxWidthController.text)
                         : null;
-                    double height = maxHeightController.text.isNotEmpty
+                    double? height = maxHeightController.text.isNotEmpty
                         ? double.parse(maxHeightController.text)
                         : null;
-                    int quality = qualityController.text.isNotEmpty
+                    int? quality = qualityController.text.isNotEmpty
                         ? int.parse(qualityController.text)
                         : null;
                     onPick(width, height, quality);
@@ -355,40 +358,40 @@ class _MyHomePageState extends State<MyHomePage> {
 }
 
 typedef void OnPickImageCallback(
-    double maxWidth, double maxHeight, int quality);
+    double? maxWidth, double? maxHeight, int? quality);
 
 class AspectRatioVideo extends StatefulWidget {
   AspectRatioVideo(this.controller);
 
-  final VideoPlayerController controller;
+  final VideoPlayerController? controller;
 
   @override
   AspectRatioVideoState createState() => AspectRatioVideoState();
 }
 
 class AspectRatioVideoState extends State<AspectRatioVideo> {
-  VideoPlayerController get controller => widget.controller;
+  VideoPlayerController? get controller => widget.controller;
   bool initialized = false;
 
   void _onVideoControllerUpdate() {
     if (!mounted) {
       return;
     }
-    if (initialized != controller.value.initialized) {
-      initialized = controller.value.initialized;
+    if (initialized != controller!.value.isInitialized) {
+      initialized = controller!.value.isInitialized;
       setState(() {});
     }
   }
 
   @override
   void initState() {
     super.initState();
-    controller.addListener(_onVideoControllerUpdate);
+    controller!.addListener(_onVideoControllerUpdate);
   }
 
   @override
   void dispose() {
-    controller.removeListener(_onVideoControllerUpdate);
+    controller!.removeListener(_onVideoControllerUpdate);
     super.dispose();
   }
 
@@ -397,8 +400,8 @@ class AspectRatioVideoState extends State<AspectRatioVideo> {
     if (initialized) {
       return Center(
         child: AspectRatio(
-          aspectRatio: controller.value?.aspectRatio,
-          child: VideoPlayer(controller),
+          aspectRatio: controller!.value.aspectRatio,
+          child: VideoPlayer(controller!),
         ),
       );
     } else {

packages/image_picker/image_picker/example/pubspec.yaml

@@ -3,24 +3,23 @@ description: Demonstrates how to use the image_picker plugin.
 author: Flutter Team <[email protected]>
 
 dependencies:
-  video_player: ^0.10.3
+  video_player: ^2.0.0-nullsafety.7
   flutter:
     sdk: flutter
-  flutter_plugin_android_lifecycle: ^1.0.2
+  flutter_plugin_android_lifecycle: ^2.0.0-nullsafety.2
   image_picker:
     path: ../
-  image_picker_for_web: ^0.1.0
 
 dev_dependencies:
   flutter_driver:
     sdk: flutter
   integration_test:
     path: ../../../integration_test
-  pedantic: ^1.8.0
+  pedantic: ^1.10.0
 
 flutter:
   uses-material-design: true
 
 environment:
-  sdk: ">=2.0.0-dev.28.0 <3.0.0"
+  sdk: ">=2.12.0-0 <3.0.0"
   flutter: ">=1.10.0 <2.0.0"

packages/image_picker/image_picker/integration_test/old_image_picker_test.dart

@@ -1,3 +1,5 @@
+// @dart=2.9
+
 import 'package:integration_test/integration_test.dart';
 
 void main() {