Merge pull request vicajilau#1567 from Sameri11/fix-issue-1555

fix default_plugin warnings with recent dart sdk

Author: navaronbracke

CHANGELOG.md

@@ -1,3 +1,8 @@
+## 8.0.7
+### General
+- Fixes an issue relating to incorrect registration of platform-specific implementations. [#1555](https://github.com/miguelpruivo/flutter_file_picker/issues/1555).
+- Fixes an issue that required users to use `kIsWeb` and `FilePickerWeb` when running on the web.
+
 ## 8.0.6
 ### Android
 Updates the minimum Android SDK version to 21, to match the current Flutter minimum Android SDK version. Fixes [#1522](https://github.com/miguelpruivo/flutter_file_picker/issues/1522), [#1528](https://github.com/miguelpruivo/flutter_file_picker/issues/1528), and [#1531](https://github.com/miguelpruivo/flutter_file_picker/issues/1531). Thanks @navaronbracke.

example/lib/generated_plugin_registrant.dart

@@ -3,3 +3,10 @@ library file_picker;
 export './src/file_picker.dart';
 export './src/platform_file.dart';
 export './src/file_picker_result.dart';
+export './src/file_picker_macos.dart';
+export './src/linux/file_picker_linux.dart';
+export './src/file_picker_io.dart';
+// Conditional export needed for web to successfully compile,
+// as `dart:ffi` is not available on the web.
+export './src/windows/file_picker_windows_stub.dart'
+    if (dart.library.ffi) './src/windows/file_picker_windows.dart';

lib/file_picker.dart

@@ -1,13 +1,7 @@
 import 'dart:async';
-import 'dart:io';
 import 'dart:typed_data';
 
-import 'package:file_picker/src/file_picker_io.dart';
-import 'package:file_picker/src/file_picker_macos.dart';
 import 'package:file_picker/src/file_picker_result.dart';
-import 'package:file_picker/src/linux/file_picker_linux.dart';
-import 'package:file_picker/src/windows/stub.dart'
-    if (dart.library.io) 'package:file_picker/src/windows/file_picker_windows.dart';
 import 'package:plugin_platform_interface/plugin_platform_interface.dart';
 
 const String defaultDialogTitle = '';
@@ -38,7 +32,7 @@ abstract class FilePicker extends PlatformInterface {
 
   static final Object _token = Object();
 
-  static FilePicker _instance = FilePicker._setPlatform();
+  static late FilePicker _instance;
 
   static FilePicker get platform => _instance;
 
@@ -47,22 +41,6 @@ abstract class FilePicker extends PlatformInterface {
     _instance = instance;
   }
 
-  factory FilePicker._setPlatform() {
-    if (Platform.isAndroid || Platform.isIOS) {
-      return FilePickerIO();
-    } else if (Platform.isLinux) {
-      return FilePickerLinux();
-    } else if (Platform.isWindows) {
-      return filePickerWithFFI();
-    } else if (Platform.isMacOS) {
-      return FilePickerMacOS();
-    } else {
-      throw UnimplementedError(
-        'The current platform "${Platform.operatingSystem}" is not supported by this plugin.',
-      );
-    }
-  }
-
   /// Retrieves the file(s) from the underlying platform
   ///
   /// Default [type] set to [FileType.any] with [allowMultiple] set to `false`.

lib/src/file_picker.dart

@@ -16,6 +16,10 @@ const EventChannel _eventChannel =
 
 /// An implementation of [FilePicker] that uses method channels.
 class FilePickerIO extends FilePicker {
+  static void registerWith() {
+    FilePicker.platform = FilePickerIO();
+  }
+
   static const String _tag = 'MethodChannelFilePicker';
   static StreamSubscription? _eventSubscription;
 

lib/src/file_picker_io.dart

@@ -4,6 +4,10 @@ import 'package:file_picker/file_picker.dart';
 import 'package:file_picker/src/utils.dart';
 
 class FilePickerMacOS extends FilePicker {
+  static void registerWith() {
+    FilePicker.platform = FilePickerMacOS();
+  }
+
   @override
   Future<FilePickerResult?> pickFiles({
     String? dialogTitle,

lib/src/file_picker_macos.dart

@@ -7,6 +7,10 @@ import 'package:file_picker/src/platform_file.dart';
 import 'package:file_picker/src/utils.dart';
 
 class FilePickerLinux extends FilePicker {
+  static void registerWith() {
+    FilePicker.platform = FilePickerLinux();
+  }
+
   @override
   Future<FilePickerResult?> pickFiles({
     String? dialogTitle,

lib/src/linux/file_picker_linux.dart

@@ -11,9 +11,11 @@ import 'package:file_picker/src/windows/file_picker_windows_ffi_types.dart';
 import 'package:path/path.dart';
 import 'package:win32/win32.dart';
 
-FilePicker filePickerWithFFI() => FilePickerWindows();
-
 class FilePickerWindows extends FilePicker {
+  static void registerWith() {
+    FilePicker.platform = FilePickerWindows();
+  }
+
   @override
   Future<FilePickerResult?> pickFiles({
     String? dialogTitle,

lib/src/windows/file_picker_windows.dart

@@ -0,0 +1,7 @@
+import 'package:file_picker/file_picker.dart';
+
+class FilePickerWindows extends FilePicker {
+  /// Errors on attempted instantiation of the stub. It exists only to satisfy
+  /// compile-time dependencies, and should never actually be created.
+  FilePickerWindows() : assert(false);
+}