stream_builder_x 1.0.0+1

Simple wrapper around StreamBuilder for selectively rebuild, optimize rebuild operations of widgets.

Simple wrapper around StreamBuilder for selectively rebuild, optimize rebuild operations of widgets.

Usage

StreamBuilderX

Wrapper around StreamBuilder add the ability to selectively determine whether to rebuild or not.

class StreamBuilderWidget extends StatelessWidget {
  const StreamBuilderWidget({Key? key, required this.controller})
      : super(key: key);
  final StreamController<StreamState> controller;

  @override
  Widget build(BuildContext context) {
    return StreamBuilderX<StreamState>(
      stream: controller.stream,
      asyncBuildWhen: (prev, curr) {
        return curr.data?.number != curr.data?.number;
      },
      builder: (context, snapshot) {
        debugPrint("built StreamBuilderWidget");
        final state = snapshot.data;
        return Text('${state?.text}/${state?.number}');
      },
    );
  }
}

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StreamSelectorX

Wrapper around [StreamBuilder] add the ability to selectively determine whether to rebuild or not.

class StreamSelectorWidget extends StatelessWidget {
  const StreamSelectorWidget({Key? key, required this.controller})
      : super(key: key);
  final StreamController<StreamState> controller;

  @override
  Widget build(BuildContext context) {
    return StreamSelectorX<StreamState, int?>(
      stream: controller.stream,
      asyncSelector: (snapshot) {
        return snapshot.data?.number;
      },
      builder: (context, snapshot) {
        debugPrint("built StreamSelectorWidget");
        return ElevatedButton(
            onPressed: () {
              if (snapshot.data == null) {
                controller.add(const StreamState(text: '', number: 0));
              } else {
                final data = snapshot.data!;
                controller.add(data.copyWith(number: data.number + 1));
              }
            },
            child: Text(snapshot.data?.number.toString() ?? 0.toString()));
      },
    );
  }
}

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StreamListenerX

Will run callbacks when a new value is emitted from the stream without rebuilding child.

class StreamListenerWidget extends StatelessWidget {
  const StreamListenerWidget({Key? key, required this.controller})
      : super(key: key);
  final StreamController<StreamState> controller;

  @override
  Widget build(BuildContext context) {
    return StreamListenerX<StreamState>(
      stream: controller.stream,
      onData: (data) {
        debugPrint("onData");
      },
      child: const Text("This will not change"),
    );
  }
}

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