A Flutter widget that makes its child "flash" on-and-off (blink).

Usage

First, import the package:

import 'package:flasher/flasher.dart';

Minimal example:

Flasher(
    child: Text('Blink'),
)

By defalt, it will carry on animating forever. Use the repeat property to modify that behaviour:

Flasher(
    repeat: 10,
    child: Text('Flash ten times'),
)

You can customise the duration; duration is how long it sits at full opacity between "flashes", flashDuration is how long it takes to "blink".

Flasher(
    flashDuration: const Duration(milliseconds: 150),
    duration: const Duration(milliseconds: 250),
    child: Text('This is the child'),
)

If you limit the number of times it flashes (using repeat), you can configure it to fade out when it's complete.

Flasher.fadeOutAfter(
    repeat: 10,
    child: Text('This is the child')
)

By default it waits a moment before fading out; modify this by setting fadeOutDelay. You can also confgiure how long it takes to fade out using fadeOutDuration.

Flasher.fadeOutAfter(
    repeat: 10,
    fadeOutDuration: const Duration(milliseconds: 350),
    fadeOutDelay: const Duration(milliseconds: 150,),
    child: Text('This is the child')
)

By default, the "flash" uses a simple easing curve (Curves.ease), but you can configue this as well:

Flasher.fadeOutAfter(
    curve: Curves.bounceInOut,
    child: Text('This is the child')
)

Finally, if you want to defer the start you can set active to false:

Flasher.fadeOutAfter(
    active: false,
    child: Text('This is the child')
)

Here's one with everything configured:

Flasher(
    active: true,
    flashDuration: const Duration(milliseconds: 150),
    duration: const Duration(milliseconds: 250),
    curve: Curves.bounceInOut,
    fadeOutDuration: const Duration(milliseconds: 350),
    fadeOutDelay: const Duration(milliseconds: 150,),
    fadeOutOnComplete: true,
    repeat: 10,
    child: Text('This is the child'),
)

Note that the child can be any Flutter widget; it's not limited to text.

The package also contains a very simple example app.