diff --git a/lib/src/colorize.dart b/lib/src/colorize.dart
index e6a4127..4ed0cdf 100644
--- a/lib/src/colorize.dart
+++ b/lib/src/colorize.dart
@@ -141,7 +141,7 @@ class _RotatingTextState extends State<ColorizeAnimatedTextKit>
 
   @override
   void dispose() {
-    _controller.dispose();
+    _controller?.dispose();
     super.dispose();
   }
 
@@ -204,9 +204,7 @@ class _RotatingTextState extends State<ColorizeAnimatedTextKit>
       _index++;
     }
 
-    if (_controller != null) _controller.dispose();
-
-    setState(() {});
+    if (mounted) setState(() {});
 
     _controller = new AnimationController(
       duration: _texts[_index]['speed'] * _texts[_index]['text'].length,
@@ -231,7 +229,7 @@ class _RotatingTextState extends State<ColorizeAnimatedTextKit>
                 curve: Interval(0.0, 1.0, curve: Curves.easeIn)))
           ..addStatusListener(_animationEndCallback);
 
-    _controller.forward();
+    _controller?.forward();
   }
 
   void _animationEndCallback(state) {
diff --git a/lib/src/fade.dart b/lib/src/fade.dart
index fce864e..6086e00 100644
--- a/lib/src/fade.dart
+++ b/lib/src/fade.dart
@@ -149,15 +149,13 @@ class _RotatingTextState extends State<FadeAnimatedTextKit>
         _texts.add({'text': widget.text[i], 'pause': _pause});
       }
     }
-
     _nextAnimation();
   }
 
   @override
   void dispose() {
-    _controller
-      ..stop()
-      ..dispose();
+    _controller?.stop();
+    _controller.dispose();
     super.dispose();
   }
 
@@ -214,9 +212,7 @@ class _RotatingTextState extends State<FadeAnimatedTextKit>
       _index++;
     }
 
-    if (_controller != null) _controller.dispose();
-
-    setState(() {});
+    if (mounted) setState(() {});
 
     _controller = new AnimationController(
       duration: _duration,
@@ -230,14 +226,14 @@ class _RotatingTextState extends State<FadeAnimatedTextKit>
         parent: _controller, curve: Interval(0.8, 1.0, curve: Curves.linear)))
       ..addStatusListener(_animationEndCallback);
 
-    _controller..forward();
+    _controller.forward();
   }
 
   void _setPause() {
     bool isLast = _index == widget.text.length - 1;
 
     _isCurrentlyPausing = true;
-    setState(() {});
+    if (mounted) setState(() {});
 
     // Handle onNextBeforePause callback
     if (widget.onNextBeforePause != null)
@@ -265,7 +261,7 @@ class _RotatingTextState extends State<FadeAnimatedTextKit>
         pause = _texts[_index]['pause'].inMilliseconds;
         left = widget.duration.inMilliseconds;
 
-        _controller.stop();
+        _controller?.stop();
 
         _setPause();
 
diff --git a/lib/src/rotate.dart b/lib/src/rotate.dart
index 071c39c..6d8bbe6 100644
--- a/lib/src/rotate.dart
+++ b/lib/src/rotate.dart
@@ -157,9 +157,8 @@ class _RotatingTextState extends State<RotateAnimatedTextKit>
 
   @override
   void dispose() {
-    _controller
-      ..stop()
-      ..dispose();
+    _controller?.stop();
+    _controller?.dispose();
     super.dispose();
   }
 
@@ -222,9 +221,7 @@ class _RotatingTextState extends State<RotateAnimatedTextKit>
       _index++;
     }
 
-    if (_controller != null) _controller.dispose();
-
-    setState(() {});
+    if (mounted) setState(() {});
 
     if (widget.transitionHeight == null) {
       _transitionHeight = widget.textStyle.fontSize * 10 / 3;
@@ -278,7 +275,7 @@ class _RotatingTextState extends State<RotateAnimatedTextKit>
     bool isLast = _index == widget.text.length - 1;
 
     _isCurrentlyPausing = true;
-    setState(() {});
+    if (mounted) setState(() {});
 
     // Handle onNextBeforePause callback
     if (widget.onNextBeforePause != null)
@@ -301,7 +298,7 @@ class _RotatingTextState extends State<RotateAnimatedTextKit>
       } else {
         pause = _texts[_index]['pause'].inMilliseconds;
 
-        _controller.stop();
+        _controller?.stop();
 
         _setPause();
 
diff --git a/lib/src/scale.dart b/lib/src/scale.dart
index 8b979e7..53befd2 100644
--- a/lib/src/scale.dart
+++ b/lib/src/scale.dart
@@ -162,10 +162,8 @@ class _RotatingTextState extends State<ScaleAnimatedTextKit>
 
   @override
   void dispose() {
-    if (_controller != null)
-      _controller
-        ..stop()
-        ..dispose();
+    _controller?.stop();
+    _controller?.dispose();
     super.dispose();
   }
 
@@ -225,8 +223,6 @@ class _RotatingTextState extends State<ScaleAnimatedTextKit>
       _index++;
     }
 
-    if (_controller != null) _controller.dispose();
-
     setState(() {});
 
     _controller = new AnimationController(
diff --git a/lib/src/text_liquid_fill.dart b/lib/src/text_liquid_fill.dart
index 0076b1f..66a8c99 100644
--- a/lib/src/text_liquid_fill.dart
+++ b/lib/src/text_liquid_fill.dart
@@ -101,16 +101,10 @@ class _TextLiquidFillState extends State<TextLiquidFill>
 
   @override
   void dispose() {
-    if (_waveController != null)
-      _waveController
-        ..stop()
-        ..dispose();
-
-    if (_loadController != null)
-      _loadController
-        ..stop()
-        ..dispose();
-
+    _waveController?.stop();
+    _waveController?.dispose();
+    _loadController?.stop();
+    _loadController?.dispose();
     super.dispose();
   }
 
diff --git a/lib/src/typer.dart b/lib/src/typer.dart
index 78651e6..ecd491f 100644
--- a/lib/src/typer.dart
+++ b/lib/src/typer.dart
@@ -133,10 +133,8 @@ class _TyperState extends State<TyperAnimatedTextKit>
 
   @override
   void dispose() {
-    if (_controller != null)
-      _controller
-        ..stop()
-        ..dispose();
+    _controller?.stop();
+    _controller?.dispose();
     super.dispose();
   }
 
@@ -187,9 +185,7 @@ class _TyperState extends State<TyperAnimatedTextKit>
       _index++;
     }
 
-    if (_controller != null) _controller.dispose();
-
-    setState(() {});
+    if (mounted) setState(() {});
 
     _controller = new AnimationController(
       duration: _texts[_index]['speed'] * _texts[_index]['text'].length,
@@ -207,7 +203,7 @@ class _TyperState extends State<TyperAnimatedTextKit>
     bool isLast = _index == widget.text.length - 1;
 
     _isCurrentlyPausing = true;
-    setState(() {});
+    if (mounted) setState(() {});
 
     // Handle onNextBeforePause callback
     if (widget.onNextBeforePause != null)
diff --git a/lib/src/typewriter.dart b/lib/src/typewriter.dart
index e0c4407..7770b85 100644
--- a/lib/src/typewriter.dart
+++ b/lib/src/typewriter.dart
@@ -151,11 +151,8 @@ class _TypewriterState extends State<TypewriterAnimatedTextKit>
 
   @override
   void dispose() {
-    if (_controller != null) {
-      _controller
-        ..stop()
-        ..dispose();
-    }
+    _controller?.stop();
+    _controller?.dispose();
     super.dispose();
   }
 
@@ -229,9 +226,7 @@ class _TypewriterState extends State<TypewriterAnimatedTextKit>
       _index++;
     }
 
-    if (_controller != null) _controller.dispose();
-
-    setState(() {});
+    if (mounted) setState(() {});
 
     _controller = new AnimationController(
       duration: _texts[_index]['speed'] * _texts[_index]['text'].length,
@@ -250,7 +245,7 @@ class _TypewriterState extends State<TypewriterAnimatedTextKit>
     bool isLast = _index == widget.text.length - 1;
 
     _isCurrentlyPausing = true;
-    setState(() {});
+    if (mounted) setState(() {});
 
     // Handle onNextBeforePause callback
     if (widget.onNextBeforePause != null)