📦 migrate to null-safety

.gitignore

@@ -1,16 +1,48 @@
-# Don’t commit the following directories created by pub.
-.buildlog
-.pub/
-build/
-packages
-.packages
-.vscode/
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
 
-# Or the files created by dart2js.
-*.dart.js
-*.js_
-*.js.deps
-*.js.map
+# The .vscode folder contains launch configuration and tasks you configure in
+# VS Code which you may wish to be included in version control, so this line
+# is commented out by default.
+#.vscode/
 
-# Include when developing application packages.
+# Flutter/Dart/Pub related
+**/doc/api/
+**/ios/Flutter/.last_build_id
+.dart_tool/
+.flutter-plugins
+.flutter-plugins-dependencies
+.packages
+.pub-cache/
+.pub/
+/build/
 pubspec.lock
+
+# Web related
+lib/generated_plugin_registrant.dart
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json
+
+# Android Studio will place build artifacts here
+/android/app/debug
+/android/app/profile
+/android/app/release
+
+ios/build

example/.gitignore

@@ -69,3 +69,4 @@ build/
 !**/ios/**/default.pbxuser
 !**/ios/**/default.perspectivev3
 !/packages/flutter_tools/test/data/dart_dependencies_test/**/.packages
+/ios/Flutter/flutter_export_environment.sh

example/android/app/build.gradle

@@ -25,7 +25,7 @@ apply plugin: 'com.android.application'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
-    compileSdkVersion 27
+    compileSdkVersion 28
 
     lintOptions {
         disable 'InvalidPackage'

example/lib/src/app.dart

@@ -24,8 +24,8 @@ class App extends StatelessWidget {
                   fontSize: 24,
                 ),
               ),
-              onPressed: (AnimationController controller) {
-                if (controller.isCompleted) {
+              onPressed: (AnimationController? controller) {
+                if (controller!.isCompleted) {
                   controller.reverse();
                 } else {
                   controller.forward();

example/pubspec.yaml

@@ -10,7 +10,7 @@ description: An example for the progress button implementation.
 version: 1.0.0+1
 
 environment:
-  sdk: ">=2.0.0-dev.68.0 <3.0.0"
+  sdk: '>=2.12.0 <3.0.0'
 
 dependencies:
   flutter:

lib/button_stagger_animation.dart

@@ -2,19 +2,19 @@ import 'package:flutter/material.dart';
 
 class ButtonStaggerAnimation extends StatelessWidget {
   // Animation fields
-  final AnimationController controller;
+  final AnimationController? controller;
 
   // Display fields
-  final Color color;
-  final Color progressIndicatorColor;
-  final double progressIndicatorSize;
-  final BorderRadius borderRadius;
-  final double strokeWidth;
-  final Function(AnimationController) onPressed;
-  final Widget child;
+  final Color? color;
+  final Color? progressIndicatorColor;
+  final double? progressIndicatorSize;
+  final BorderRadius? borderRadius;
+  final double? strokeWidth;
+  final Function(AnimationController?)? onPressed;
+  final Widget? child;
 
   ButtonStaggerAnimation({
-    Key key,
+    Key? key,
     this.controller,
     this.color,
     this.progressIndicatorColor,
@@ -30,16 +30,16 @@ class ButtonStaggerAnimation extends StatelessWidget {
     return LayoutBuilder(builder: _progressAnimatedBuilder);
   }
 
-  Widget _buttonChild() {
-    if (controller.isAnimating) {
+  Widget? _buttonChild() {
+    if (controller!.isAnimating) {
       return Container();
-    } else if (controller.isCompleted) {
+    } else if (controller!.isCompleted) {
       return OverflowBox(
         maxWidth: progressIndicatorSize,
         maxHeight: progressIndicatorSize,
         child: CircularProgressIndicator(
-          strokeWidth: strokeWidth,
-          valueColor: AlwaysStoppedAnimation<Color>(progressIndicatorColor),
+          strokeWidth: strokeWidth!,
+          valueColor: AlwaysStoppedAnimation<Color?>(progressIndicatorColor),
         ),
       );
     }
@@ -57,7 +57,7 @@ class ButtonStaggerAnimation extends StatelessWidget {
       end: buttonHeight,
     ).animate(
       CurvedAnimation(
-        parent: controller,
+        parent: controller!,
         curve: Curves.easeInOut,
       ),
     );
@@ -66,12 +66,12 @@ class ButtonStaggerAnimation extends StatelessWidget {
       begin: borderRadius,
       end: BorderRadius.all(Radius.circular(buttonHeight / 2.0)),
     ).animate(CurvedAnimation(
-      parent: controller,
+      parent: controller!,
       curve: Curves.easeInOut,
     ));
 
     return AnimatedBuilder(
-      animation: controller,
+      animation: controller!,
       builder: (context, child) {
         return SizedBox(
           height: buttonHeight,
@@ -83,7 +83,7 @@ class ButtonStaggerAnimation extends StatelessWidget {
             color: color,
             child: _buttonChild(),
             onPressed: () {
-              this.onPressed(controller);
+              this.onPressed!(controller);
             },
           ),
         );

lib/progress_button.dart

@@ -6,28 +6,34 @@ import 'package:progress_indicator_button/button_stagger_animation.dart';
 class ProgressButton extends StatefulWidget {
   /// The background color of the button.
   final Color color;
+
   /// The progress indicator color.
   final Color progressIndicatorColor;
+
   /// The size of the progress indicator.
   final double progressIndicatorSize;
+
   /// The border radius while NOT animating.
   final BorderRadius borderRadius;
+
   /// The duration of the animation.
   final Duration animationDuration;
 
   /// The stroke width of progress indicator.
   final double strokeWidth;
+
   /// Function that will be called at the on pressed event.
   ///
   /// This will grant access to its [AnimationController] so
   /// that the animation can be controlled based on the need.
-  final Function(AnimationController) onPressed;
+  final Function(AnimationController?) onPressed;
+
   /// The child to display on the button.
   final Widget child;
 
   ProgressButton({
-    @required this.child,
-    @required this.onPressed,
+    required this.child,
+    required this.onPressed,
     this.color = Colors.blue,
     this.strokeWidth = 2,
     this.progressIndicatorColor = Colors.white,
@@ -42,7 +48,7 @@ class ProgressButton extends StatefulWidget {
 
 class _ProgressButtonState extends State<ProgressButton>
     with TickerProviderStateMixin {
-  AnimationController _controller;
+  late AnimationController _controller;
 
   @override
   void initState() {
@@ -64,7 +70,7 @@ class _ProgressButtonState extends State<ProgressButton>
   Widget build(BuildContext context) {
     return Center(
       child: ButtonStaggerAnimation(
-        controller: _controller.view,
+        controller: _controller.view as AnimationController?,
         color: widget.color,
         strokeWidth: widget.strokeWidth,
         progressIndicatorColor: widget.progressIndicatorColor,

pubspec.yaml

@@ -5,7 +5,7 @@ author: Pascal Brosinski<pascal@brosinski.eu>
 homepage: https://github.com/PascalAC/progress_button
 
 environment:
-  sdk: ">=2.0.0-dev.68.0 <3.0.0"
+  sdk: '>=2.12.0 <3.0.0'
 
 dependencies:
   flutter:

test/progress_button_test.dart

@@ -13,6 +13,6 @@ void main() {
     await tester.tap(find.byType(RaisedButton));
 
     final widget = tester.widget<ButtonStaggerAnimation>(find.byType(ButtonStaggerAnimation));
-    expect(widget.controller.isAnimating, true);
+    expect(widget.controller!.isAnimating, true);
   });
 }