perfect IconToggle

lib/icon_toggle.dart

@@ -41,6 +41,7 @@ class _IconToggleState extends State<IconToggle>
     with SingleTickerProviderStateMixin {
   AnimationController _controller;
   Animation<double> _position;
+  bool _cancel = false;
 
   @override
   void initState() {
@@ -51,7 +52,9 @@ class _IconToggleState extends State<IconToggle>
         reverseDuration: Duration(milliseconds: 50));
     _position = CurvedAnimation(parent: _controller, curve: Curves.linear);
     _position.addStatusListener((status) {
-      if (status == AnimationStatus.dismissed && widget.onChanged != null) {
+      if (status == AnimationStatus.dismissed &&
+          widget.onChanged != null &&
+          _cancel == false) {
         widget.onChanged(!widget.value);
       }
     });
@@ -66,12 +69,20 @@ class _IconToggleState extends State<IconToggle>
   @override
   Widget build(BuildContext context) {
     return GestureDetector(
+      behavior: HitTestBehavior.opaque,
       onTapDown: (event) {
+        _cancel = false;
         _controller?.forward();
       },
       onTapUp: (event) {
         _controller?.reverse();
       },
+      onTapCancel: () {
+        _cancel = true;
+        _controller?.reverse();
+      },
+      child: Padding(
+        padding: const EdgeInsets.all(10.0),
         child: _IconToggleable<double>(
           listenable: _position,
           activeColor: widget.activeColor,
@@ -88,6 +99,7 @@ class _IconToggleState extends State<IconToggle>
             ),
           ),
         ),
+      ),
     );
   }
 }
@@ -131,7 +143,7 @@ class _IconPainter extends CustomPainter {
   void paint(Canvas canvas, Size size) {
     final Paint paint = Paint()
       ..color = Color.lerp(inactiveColor, activeColor, _value)
-          .withOpacity(math.min(_value, 0.1))
+          .withOpacity(math.min(_value, 0.15))
       ..style = PaintingStyle.fill
       ..strokeWidth = 2.0;
     canvas.drawCircle(