Adding Feedback in UI: Bringing the Shake Text Effect to Life in Flutter

Ready to take your Flutter UI to the next level?

The Shake Text Effect is a fun and dynamic way to captivate users. It delivers real-time visual feedback by shaking text when errors occur. Whether it’s an invalid password or an empty field, this eye-catching animation draws attention to exactly where it’s needed. Using the shake effect, you can create animations that enhances user interaction, making the interface both engaging and functional.

In this post, we’ll guide you through the exciting process of integrating the shake effect into your Flutter app—bringing your text widgets to life with style and purpose!

Basics of Text Widgets in Flutter

Before venturing into the shake text, let’s summarize the basic text widgets. In any Flutter app, the final widget child (like Text or TextFormField) depicts what the user sees on the screen. These child Widgets can then be customized to suit your needs.

For instance:

const Text(
    'This is a basic Text Widget in Flutter',
),

In another case, for a text input field, we use the TextFormField widget.

What is the shake text effect in Flutter?

This effect creates a unique user interface experience by adding a shaking animation to the text widget when certain conditions are met. Developers often use this effect in Flutter where an error occurs, to enhance the visual cues provided to users.

For example, when users enter invalid input into a form, it helps to draw the users’ attention to the error they made.

Shake TextField Widget in Flutter

Shake TextField Flutter is a favorite widget of many that allows developers to enhance the functionality of the TextField widget by applying a shake animation effect on it. This animation gives a feedback mechanism when users make a mistake.

The shake effect can not only be applied to a text widget but also to any given child widget in a Flutter app.

Building a Flutter Shaking Text Effect from Scratch

Let’s dive into how to integrate it in a Flutter application. We’ll create a new shake effect for our Flutter Text Widget right from the ground up. Let’s start with boilerplate code for a flutter widget, making sure to use helpful tools like a builder context child. Remember, always build one point at a time to avoid errors.

class ShakeError extends StatefulWidget {
  final Widget child;

  const ShakeError({Key key, this.child}) : super(key: key);

  _ShakeErrorState createState() => _ShakeErrorState();
}
     

The provided class shakeerror extends StatefulWidget, because the state should change upon an entrust error. The StatefulWidget calls createState() to create a separate state object.

Building the State for ShakeError Widget

Having set up our ShakeError widget, we now create the state for it. We do this by defining a class that extends the State object. Here, the buildcontext context is passed to the build method allowing the recreation of the widget tree.

class _ShakeErrorState extends State<ShakeError> {
  Animation<double> _doubleAnim;
  AnimationController _animationController;

  @override
  void initState() {
    super.initState();
    _animationController = AnimationController(
      duration: const Duration(milliseconds: 100),
      vsync: this,
    );
    _doubleAnim = Tween(begin: -5.0, end: 5.0).animate(_animationController)
      ..addListener(() {
        setState(() {});
      });
  }

  @override
  Widget build(BuildContext context) {
    return Transform.translate(
      offset: Offset(_doubleAnim.value, 0),
      child: widget.child,
    );
  }

  @override
  void dispose() {
    _animationController.dispose();
    super.dispose();
  }
}

This class extends the state of ShakeError, implementing three primary methods: Build, Dispose, and InitState. The void initstate initializes an AnimationController that uses a given duration and passes the context to the build method.

Creating a Shake Animation

Great! Now, adding the shake animation is handled in our animation controller class within the _ShakeErrorState class. Here, we customize and define shake duration, shake distance, and much more.

With the initState() method, the AnimationController is initialized. The details of the animation, such as duration, are defined in this section. Also, the Tween animation parameters are set in this section with a begin and end value, which effectively means we want to shake our text widget side-to-side by 5 pixels.

@override
void initState() {
  super.initState();
  _animationController = AnimationController(
    duration: const Duration(milliseconds: 100),
    vsync: this,
  );
  _doubleAnim = Tween(begin: -5.0, end: 5.0).animate(_animationController)
    ..addListener(() {
      setState(() {});
    });
}

In the build method, return Transform.translate applies the shake effect to the child widget provided to our ShakeEffect widget, by translating it side-to-side.

@override
Widget build(BuildContext context) {
  return Transform.translate(
    offset: Offset(_doubleAnim.value, 0),
    child: widget.child,
  );
}

The shake effect’s duration and intensity can be easily customized using the Duration and Tween values in the animation parameters of our initState() method. Adjust these values as per requirements to get the desired flutter text shake effect.

Triggering the Shake Animation Effect

Let’s make our exploration more interactive by triggering the shake animation effect when an error occurs. So instead of constantly shaking, we want our text widget only to shake when an error occurs.

void shake() {
  _animationController
      .forward(from: 0)
      .then((value) => _animationController.reverse());
}

The above void shake function starts the animation when called, shakes the widget (many times if you wish using a loop), and then reverses back to its original state. This completes our shake effect, giving us a flutter shake TextField widget ready to use in our flutter apps.

We can call the shake method in situations where a shake effect is necessary. For instance, we can use it when an incorrect or empty value is submitted in a form.

Practical Application Of The Effect

Applying the shaking text effect in a real-world context enriches user interface interactions. A practical application would be shaking the TextField widget when it’s empty or an inappropriate value is passed.

Below, we have a complete TextField widget with the shake animation effect applied.

class MyHomePage extends StatelessWidget {
  final TextEditingController controller = TextEditingController();

  MyHomePage({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    final _shakeKey = GlobalKey<_ShakeErrorState>();
    return Scaffold(
      appBar: AppBar(
        title: Text('Shake TextField Demo'),
      ),
      body: ShakeError(
        key: _shakeKey,
        child: Padding(
          padding: const EdgeInsets.all(20.0),
          child: TextField(
            controller: controller,
            decoration: const InputDecoration(
              labelText: 'Enter some text',
            ),
          ),
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () {
          if (controller.text.isEmpty) {
            _shakeKey.currentState.shake();
          }
        },
        child: Icon(Icons.text_fields),
      ),
    );
  }
}

Here, class MyHomePage extends StatelessWidget enables the Stateless nature of our homepage. The build method is employed where the Scaffold widget returns the final interface. This includes an AppBar, a defined body, and a floating button that commands the shake effect to the TextField when no text is provided.

In this setup, the animation is controlled by the final Duration shakeDuration parameter, which defines the time span of the shake effect. This ensures that the shake animation is executed smoothly and consistently, providing a seamless user experience. Thus, the Shake Text Effect can be a useful tool when we want to notify users of actions needed seamlessly.

Common Challenges and Their Solutions

As developers, we often run into a few issues when implementing new features. Here are some common challenges while applying the shake effect and how to overcome them:

• Continuous shaking: The shaking effect may continuously occur without stopping. Remember the use of _animationController.reverse() in the shake function to ensure the animation returns to its initial state.
• Lack of shaking: If the shake effect is not visible, check the given child to ensure it conforms to the requirements and responds correctly to the shake commands.

Testing and Debugging

To ensure your shake effect runs smoothly, it’s crucial to test the source code at various stages of development. Flutter has debugging tools integrated into its framework, making this process easier.

If an error occurs, check the console logs and carefully trace each widget’s state involved in the shake animation.

Best Practices

Here are a few tips to keep in mind while implementing a shaking text in Flutter:

• Make sure to dispose of your animation controller using the void dispose method to prevent memory leaks.
• Use the shake effect judiciously to avoid overwhelming users.
• Test the shake effect across multiple device screens, as Flutter supports cross-platform development.

Now It’s Your Turn: Transform UI Dynamics with Shake Text Effect

In this blog, we’ve explored how to implement the shake text effect in Flutter, transforming a simple text widget into a dynamic and responsive UI element. The shake effect is an excellent way to provide instant visual feedback, making your Flutter apps more engaging and user-friendly.

Now it’s your turn! Pick up your developer tools and start experimenting with Flutter animations. Happy Fluttering!

Now it’s your turn! Pick up your developer tools and experiment with various Flutter animations. Happy Flutterinnng!