Merge pull request #2033 from NatsuOnFire/feature/add_ticker_provider_mixin

Add GetTickerProviderStateMixin when multiple AnimationController objects are used

@@ -36,13 +36,13 @@ mixin GetSingleTickerProviderStateMixin on GetxController
       if (_ticker == null) return true;
       throw FlutterError.fromParts(<DiagnosticsNode>[
         ErrorSummary(
-            '$runtimeType is a SingleTickerProviderStateMixin but multiple tickers were created.'),
+            '$runtimeType is a GetSingleTickerProviderStateMixin but multiple tickers were created.'),
         ErrorDescription(
-            'A SingleTickerProviderStateMixin can only be used as a TickerProvider once.'),
+            'A GetSingleTickerProviderStateMixin can only be used as a TickerProvider once.'),
         ErrorHint(
           'If a State is used for multiple AnimationController objects, or if it is passed to other '
           'objects and those objects might use it more than one time in total, then instead of '
-          'mixing in a SingleTickerProviderStateMixin, use a regular TickerProviderStateMixin.',
+          'mixing in a GetSingleTickerProviderStateMixin, use a regular GetTickerProviderStateMixin.',
         ),
       ]);
     }());
@@ -66,7 +66,7 @@ mixin GetSingleTickerProviderStateMixin on GetxController
       throw FlutterError.fromParts(<DiagnosticsNode>[
         ErrorSummary('$this was disposed with an active Ticker.'),
         ErrorDescription(
-          '$runtimeType created a Ticker via its SingleTickerProviderStateMixin, but at the time '
+          '$runtimeType created a Ticker via its GetSingleTickerProviderStateMixin, but at the time '
           'dispose() was called on the mixin, that Ticker was still active. The Ticker must '
           'be disposed before calling super.dispose().',
         ),
@@ -82,6 +82,99 @@ mixin GetSingleTickerProviderStateMixin on GetxController
   }
 }
 
+/// Used like `TickerProviderMixin` but only with Get Controllers.
+/// Simplifies multiple AnimationController creation inside GetxController.
+///
+/// Example:
+///```
+///class SplashController extends GetxController with
+///    GetTickerProviderStateMixin {
+///  AnimationController first_controller;
+///  AnimationController second_controller;
+///
+///  @override
+///  void onInit() {
+///    final duration = const Duration(seconds: 2);
+///    first_controller =
+///        AnimationController.unbounded(duration: duration, vsync: this);
+///    second_controller =
+///        AnimationController.unbounded(duration: duration, vsync: this);
+///    first_controller.repeat();
+///    first_controller.addListener(() =>
+///        print("Animation Controller value: ${first_controller.value}"));
+///    second_controller.addListener(() =>
+///        print("Animation Controller value: ${second_controller.value}"));
+///  }
+///  ...
+/// ```
+mixin GetTickerProviderStateMixin on GetxController implements TickerProvider {
+  Set<Ticker>? _tickers;
+
+  @override
+  Ticker createTicker(TickerCallback onTick) {
+    _tickers ??= <_WidgetTicker>{};
+    final result = _WidgetTicker(onTick, this, debugLabel: kDebugMode ? 'created by ${describeIdentity(this)}' : null);
+    _tickers!.add(result);
+    return result;
+  }
+
+  void _removeTicker(_WidgetTicker ticker) {
+    assert(_tickers != null);
+    assert(_tickers!.contains(ticker));
+    _tickers!.remove(ticker);
+  }
+
+  void didChangeDependencies(BuildContext context) {
+    final muted = !TickerMode.of(context);
+    if (_tickers != null) {
+      for (final ticker in _tickers!) {
+        ticker.muted = muted;
+      }
+    }
+  }
+
+  @override
+  void onClose() {
+    assert(() {
+      if (_tickers != null) {
+        for (final ticker in _tickers!) {
+          if (ticker.isActive) {
+            throw FlutterError.fromParts(<DiagnosticsNode>[
+              ErrorSummary('$this was disposed with an active Ticker.'),
+              ErrorDescription(
+                '$runtimeType created a Ticker via its GetTickerProviderStateMixin, but at the time '
+                    'dispose() was called on the mixin, that Ticker was still active. All Tickers must '
+                    'be disposed before calling super.dispose().',
+              ),
+              ErrorHint(
+                'Tickers used by AnimationControllers '
+                    'should be disposed by calling dispose() on the AnimationController itself. '
+                    'Otherwise, the ticker will leak.',
+              ),
+              ticker.describeForError('The offending ticker was'),
+            ]);
+          }
+        }
+      }
+      return true;
+    }());
+    super.onClose();
+  }
+
+}
+
+class _WidgetTicker extends Ticker {
+  _WidgetTicker(TickerCallback onTick, this._creator, { String? debugLabel }) : super(onTick, debugLabel: debugLabel);
+
+  final GetTickerProviderStateMixin _creator;
+
+  @override
+  void dispose() {
+    _creator._removeTicker(this);
+    super.dispose();
+  }
+}
+
 @Deprecated('use GetSingleTickerProviderStateMixin')
 
 /// Used like `SingleTickerProviderMixin` but only with Get Controllers.