Mixin Collections

field_debounce_mixin.dart

import 'dart:async';

import 'package:flutter/widgets.dart';

/// provide single [TextField] debounce timer and handle controller and callback
/// by implementing [SingleFieldDebounceState] in [State] class
///
mixin SingleFieldDebounceProvider<T extends StatefulWidget>
    on SingleFieldDebounceState<T> {
  Timer _debouncedSearchTimer;
  final TextEditingController debouncedController = TextEditingController();

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

    debouncedController.dispose();
    _debouncedSearchTimer?.cancel();
  }

  /// can be used to fill [TextField.onChanged] event
  ///
  void onDebounceFieldChange(String value) {
    if (_debouncedSearchTimer != null) {
      _debouncedSearchTimer.cancel();
    }

    _debouncedSearchTimer = Timer(_debounceDuration, () {
      onDebounceDone(value);
    });
  }
}

abstract class SingleFieldDebounceState<T extends StatefulWidget>
    extends State<T> {
  void onDebounceDone(String value);

  Duration get _debounceDuration => const Duration(milliseconds: 700);
}

store_completer_mixin.dart

import 'dart:async';

/// This mixin can help you
mixin StoreCompleterMixin {
  /// completer is used because of getting from storage is asynchronous
  final Completer<bool> storeCompleter = Completer<bool>();

  /// [completed] can be used to check whether data is ready
  Future<bool> completed({
    Duration timeoutDuration = const Duration(seconds: 5),
  }) async {
    try {
      final bool completed = await storeCompleter.future
          .timeout(timeoutDuration)
          .catchError(() => false);

      return completed && storeCompleter.isCompleted;
    } catch (e) {
      return false;
    }
  }

  void maySetComplete() {
    if (!storeCompleter.isCompleted) {
      storeCompleter.complete(true);
    }
  }
}