Custom Refresh Indicator

A flutter package that allows you to easily create a custom refresh indicator widget.

TLDR; ONLINE DEMO!

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QUICK START

CustomRefreshIndicator(
  /// Scrollable widget
  child: ListView.separated(
    itemBuilder: (BuildContext context, int index) => const SizedBox(
      height: 100,
    ),
    separatorBuilder: (BuildContext context, int index) =>
        const SizedBox(height: 20),
  ),
  /// Custom indicator builder function
  builder: (
    BuildContext context,
    Widget child,
    IndicatorController controller,
    ) {
      /// TODO: Implement your own refresh indicator
      return Stack(
        children: <Widget>[
          AnimatedBuilder(
            animation: controller,
            builder: (BuildContext context, _) {
              /// This part will be rebuild on every controller change
              return MyIndicator();
            },
          ),
          /// Scrollable widget that was provided as [child] argument
          ///
          /// TIP:
          /// You can also wrap [child] with [Transform] widget to also a animate list transform (see example app)
          child,
        ],
      );
    }
  /// A function that's called when the user has dragged the refresh indicator
  /// far enough to demonstrate that they want the app to refresh.
  /// Should return [Future].
  onRefresh: myAsyncRefreshMethod,
)

Examples

Almost all of these examples are available in the example application.

Plane indicator [SOURCE][DEMO]	Ice cream [SOURCE][DEMO]	Warp [SOURCE][DEMO]

With complete state [SOURCE][DEMO]	Pull to fetch more [SOURCE][DEMO]	Envelope [SOURCE][DEMO]

Programmatically controlled [SOURCE][DEMO]	Your indicator	Your indicator
	Have you created a fancy refresh indicator? This place is for you. Open PR.	Have you created a fancy refresh indicator? This place is for you. Open PR.

Documentation

CustomRefreshIndicator widget

The CustomRefreshIndicator widget provides an absolute minimum functionality that allows you to create and set your own custom indicators.

onStateChanged

The onStateChanged callback is called everytime IndicatorState has been changed.
This is a convenient place for tracking indicator state changes. For a reference take a look at the example check mark indicator widget.

Example usage:

CustomRefreshIndicator(
  onRefresh: onRefresh,
  // You can track state changes here.
  onStateChanged: (IndicatorStateChange change) {
    if (change.didChange(from: IndicatorState.dragging, to: IndicatorState.armed)) {
      // Do something...
    } else if(change.didChange(to: IndicatorState.idle)) {
      // Do something...
    }
    // And so on...
  }
  // ...
)

IndicatorController

Controller state and value changes.

The best way to understand how the CustomRefreshIndicator widget changes its controller data is to see the example 😉. An example is available in the example application.

Online example

state	value	value description	Description
idle	==0.0	Value eqals 0.0.	No user action.
dragging	=<0.0	Value is eqal 0.0 or larger but lower than 1.0.	User is dragging the indicator.
armed	>=1.0	Value is larger than 1.0.	User dragged the indicator further than the distance declared by extentPercentageToArmed or offsetToArmed. User still keeps the finger on the screen.
loading	>=1.0	Value decreses from last armed state value in duration of armedToLoadingDuration argument to 1.0.	User finished dragging (took his finger off the screen), when state was equal to armed. onRefresh function is called.
hiding	<=1.0	Value decreses in duration of draggingToIdleDuration or loadingToIdleDuration arguments to 0.0.	Indicator is hiding after: - User ended dragging when indicator was in dragging state. - Future returned from onRefresh function is resolved. - Complete state ended. - User started scrolling through the list.
complete	==1.0	Value equals 1.0 for duration of completeStateDuration argument.	This state is OPTIONAL, provide completeStateDuration argument with non null value to enable it. Loading is completed.

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Support

If you like this package, you have learned something from it, or you just don't know what to do with your money 😅 just buy me a cup of coffee ☕️ and this dose of caffeine will put a smile on my face which in turn will help me improve this package. Also as a thank you, you will be mentioned in this readme as a sponsor.

Have a nice day! 👋